Tuning matching circuits for transmitter and receiver bands as a function of the transmitter metrics

- NXP USA, Inc.

A system can obtain an operational metric associated with the transceiver, determine a target figure of merit based on a compromise between a desired transmitter performance and a desired receiver, determine a current figure of merit based on the operational metric, and adjust the variable reactance component of the impedance matching circuit based on a comparison of the current figure of merit with the target figure of merit. Other embodiments are disclosed.

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Description
CROSS-REFERENCE TO RELATED APPLICATIONS

Notice: More than one reissue application has been filed for the reissue of U.S. Pat. No. 8,798,555. The Reissue applications are application Ser. No. 14/716,014, and the present application filed herewith. This application is a continuation of co-pending reissue application of U.S. patent application Ser. No. 14/716,014, filed May 19, 2015, which is an application for reissue of U.S. Pat. No. 8,798,555, issued on Aug. 5, 2014, from U.S. patent application Ser. No. 13/693,388, which is a continuation of U.S. patent application Ser. No. 13/168,529, filed on Jun. 24, 2011, now U.S. Pat. No. 8,428,523, which is a continuation of U.S. patent application Ser. No. 11/940,309 filed on Nov. 14, 2007, now U.S. Pat. No. 7,991,363, the disclosures of all of which are hereby incorporated by reference in their entirety.

FILED OF THE DISCLOSURE

The present invention is directed towards impedance matching circuits and more particularly, adaptive impedance matching circuits to improve transceiver operation in a variety of scenarios.

BACKGROUND OF THE INVENTION

As more technology and features are incorporated into small packages, engineering teams must get more and more creative, especially in the face of lagging miniaturization of parts and components. One of the areas that engineers focus on is multipurpose circuitry or, circuitry that meets a variety of functions. A good example of this focus is with regards to antenna matching circuits within cellular telephone devices.

Cellular telephone devices have migrated from single cellular technology supporting devices to multi-cellular technology devices integrating a variety of other consumer features such as MP3 players, color displays, games, etc. Thus, not only are the cellular telephone devices required to communicate at a variety of frequencies, they are also subjected to a large variety of use conditions. All of these factors can result in a need for different impedance matching circuits for the antenna. However, by utilizing tunable components, a single matching circuit can be used under a variety of circumstances. Tunable matching circuits generally operate to adjust the impedance match with an antenna over a frequency range to maximize the output power. However, difficulties arise when attempting to tune the matching circuit for signal reception. What is needed in the art is an adaptive impedance matching module that can operate to optimize performance of both the transmitter and the receiver under a variety of circumstances. Further, what is needed is an adaptive impedance matching module that optimizes performance of the transceiver based on optimizing the operation in view of a figure of merit.

BRIEF SUMMARY OF THE INVENTION

In general, embodiments of the invention include a tunable matching circuit and an algorithm for adjusting the same. More particularly, the tuning circuit is adjusted primarily based on transmitter oriented metrics and is then applied to attain a desired tuning for both transmitter and receiver operation. In a time division multiplexed (TDM) system in which the transmitter and the receiver operate at different frequencies but are only keyed in their respective time slots (i.e. transmit time slot and receive time slot), this is accomplished by identifying an optimal tuning for the transmitter and then adding an empirically derived adjustment to the tuning circuit in receive mode. In a frequency division multiplexed (FDM) system in which the transmitter and receiver operate simultaneously and at different frequencies, this is accomplished by identifying a target operation for the transmitter, and then adjusting the tuning circuit first to the target value for the transmitter and then adjusting the values to approach a compromised value proximate to an equal or desired target value for the receiver.

An exemplary embodiment of the present invention provides a method for controlling a matching circuit for interfacing an antenna with a transceiver. The matching circuit includes one or more tunable components. The tuning of the matching circuit is based on a figure of merit that incorporates one or more operation metrics. One aspect of the present invention is that the operation metrics can be transmitter based but still provide desired adjustment results for receiver operation. The operation metric(s) is monitored and measured and then compared to the figure of merit. If the desired operation is not attained, the variable component(s) of the matching circuit is adjusted using one or more of a variety of techniques to attain the figure of merit. This process is performed to maintain operation at the figure of merit.

In one embodiment of the invention more particularly suited for TDM systems, an offset, scaling factor, translation or other change or modification is applied to the adjustments of the variable components when switching from the transmit mode to the receive mode. This translation is a function of the values obtained while adjusting during the transmit time slot. The translation is then removed upon return to the transmitter mode and the adjustment process is resumed.

In another embodiment of the invention particularly suited for FDM systems, the figure of merit not only incorporates the transmit metrics, but also incorporates an element to attain a compromise between optimal transmitter and optimal receiver operation. This is accomplished by identifying a target operation goal, such as a desired transmitter and receiver reflection loss and then identifying an operational setting that is a close compromise between the two. This embodiment thus incorporates not only transmitter metrics but also tuning circuit settings or preferences into the algorithm. The tuning preferences can be empirically identified to ensure the desired operation.

These and other aspects, features and embodiments of the present invention will be more appreciated upon review of the figures and the detailed description.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

FIG. 1 is a block diagram illustrating an exemplary environment for deployment of one or more embodiments of the present invention.

FIG. 2 is a circuit diagram illustrating further details of an exemplary matching circuit that could be included in the AIMM in an exemplary embodiment of the present invention.

FIG. 3 is a flow diagram illustrating the general steps taken in an exemplary embodiment of the present invention.

FIG. 4 and FIG. 4A are a plots of the transmitter reflection losses for four operating frequencies.

FIG. 5 is a flow diagram illustrating the steps involved in an exemplary embodiment of the present invention operating in a TDM environment.

FIG. 6 is a return loss contour diagram in the PTC plane for a particular frequency (i.e., 825 MHz/870 MHz operation).

FIG. 7 is a flow diagram illustrating the steps involved in an exemplary embodiment of the present invention in obtaining the preference values for PTC1 and PTC2.

FIG. 8 is a contour plot showing the magnitude and the phase of the reflection coefficient.

 DETAILED DESCRIPTION OF THE INVENTION

The present invention, as well as features and aspects thereof, is directed towards providing an impedance matching circuit, module or component that in response to sensing the matching condition by monitoring one or more metrics or parameters of the transmitter, can be adjusted to optimize the match.

More specifically, embodiments of the present invention include adaptive impedance matching circuits, modules, IC's etc., that operate to sense the matching condition of the transmit signal or other transmitter related metric and then optimizes the matching characteristics by adjusting the values of one or more tunable devices in view of attaining or reaching a figure of merit. The figure of merit can be based on a variety of elements, such as the input return loss, output power, current drain, linearity metrics, as well as others. In the embodiments of the present invention that are presented herein, the figure of merit is typically described or defined as being based on the input return loss. However, it is to be understood that this is just a non-limiting example of the present invention, and although it may in and of itself be considered as novel, other transmitter, or non-receiver, related metrics may be incorporated into the figure of merit in addition to or in lieu of the input return loss or reflection loss.

In an exemplary embodiment, an adaptive impedance matching module (AIMM) detects transmitter related metrics and optimizes the matching circuit keyed on the transmit signal. A benefit associated with focusing on the transmit signal, as well as other transmitter metrics, is that the transmit signal is higher in power than the receive signal and thus, is easier to detect. However, it will be appreciated by those skilled in the art that it is desirable to improve the matching conditions for both the transmit signal and the receive signal. Advantageously, the present invention operates to optimize a figure of merit that achieves a desired operation of both signals even though the matching adjustments performed by the AIMM are only based on sensing the transmitter related metrics.

One embodiment of the invention is particularly well suited for operating in a time division multiplexed (TDM) system. In a TDM system, the radio transmits and receives in different time slots. Typically, the transmitter and receiver also operate on different frequencies; however, it will be appreciated that some systems utilize the same frequency for transmission and reception. Nonetheless, in a TDM system, the transmitter and receiver are not active at the same time. In this environment, the AIMM can be adjusted to optimal settings for the transmitter during a transmit time slot and then the AIMM can be adjusted to optimal setting for the receiver during the receive time slot. As such, the AIMM tuner can be set differently during transmit and receive time slots. During the transmit time slot, an adjustment algorithm is applied to determine the appropriate settings of the AIMM to optimize the match or attain a figure of merit that results in achieving or approaching a desired level of operation. Because any frequency offset between the transmit signal and the receive signal is known, an adjustment or modification of the setting of the AIMM in the form of a translation or some other function is applied to the AIMM during the receive time slot. The adjustment improves the matching characteristics at the receiver frequency based on knowledge determined during the transmit time slot and the general operation of the receiver. During the next transmit time slot, the translation is removed from the AIMM and the adjustment algorithm regains control of the AIMM. Upon returning to the receive time slot, the modification can be reapplied or, if the settings during the transmit time slot have been changed, then the new settings can be modified for the subsequent receive time slot.

The adjustment applied to the AIMM during the receive time slot can be obtained in a variety of manners. For instance, in one embodiment the adjustment may be a translation derived empirically by characterizing the tuner at the transmitter and receiver frequencies and then deriving a mapping function to describe the translation. Alternatively, the translation may be derived by using the known (or theoretical) S-parameters of the tuner network.

Another embodiment of the present invention is particularly suited for a Frequency Division Multiplexed (FDM) system. In an FDM system, the radio transmits and receives at the same time but at different frequencies. Unlike the embodiment suited for a TDM application, the FDM application requires the AIMM to use the same tuning condition for both transmitter and receiver operation. In this embodiment, the tuner is adjusted to provide a desired compromise between matching at the transmit frequency and matching at the receive frequency. It will be appreciated that this compromise could be attained by simply defining a figure of merit that incorporates both a transmitter metric and a receiver metric. However, as previously mentioned, the receive signal is typically lower than the transmit signal and as such, it may be difficult to accurately sense and use as a metric.

Thus, in this embodiment, non-receiver related metrics are used to find a desired compromised state for tuning the AIMM. It will be appreciated that the desired compromised state can vary based on embodiment and operational requirements. For instance, in some embodiments, transmission of data may be more important than reception and as such, preference may be given to optimizing the transmitter. Such a situation may exist in an emergency radio system that is used by people in the field and that need to report back to a central location, but are not necessarily dependent upon information from that central location. In other embodiments, the reception of data may be more important than the transmission. For instance, the reception of weather related information as an emergency warning system. In such an embodiment, preference may be given to optimizing the receiver. Yet in other embodiments, both the reception and transmission of data may be equally important and as such, a setting that gives a compromised performance or attempts to equalize the performance of both the transmitter and receiver is desired. Such an embodiment is typical of cellular telephone operation.

The FDM suitable embodiments of the present invention operate to obtain a desired level of operation based on one or more transmitter related metrics, and also incorporate known characteristics about the tuning circuits to achieve the desired operating state. The desired operating state typically reflects a state of operation that is a compromise from the optimal states for the transmitter and receiver. For instance, one embodiment of the present invention may include the tuning states of the tunable devices in the matching circuit within a transmit signal based figure of merit. Advantageously, this aspect of the present invention enables improved performance in the receive band without having to take a receiver measurement.

Another embodiment of the invention deployable within an FDM environment is to tune the matching circuit to a figure of merit that is based on a vector measurement of the transmitter reflection coefficient. In this embodiment, the phase information in the vector measurement is incorporated into the figure of merit and the optimal compromise between the transmitter and receiver operation occurs at a particular phase of the transmitter reflection coefficient.

Now turning to the figures, the various embodiments, features, aspects and advantages of the present invention are presented in more detail.

FIG. 1 is a block diagram illustrating an exemplary environment for deployment of one or more embodiments of the present invention. The illustrated embodiment includes an adaptive impedance matching module (AIMM) 100, however, it should be appreciated that the invention can be incorporated into embodiments that utilize discrete components, integrated circuits, a combination of software, firmware and hardware, or the like, and that the embodiment presented as a module is a non-limiting example. Further, although the present invention is described within the context of an AIMM, it will be appreciated that various aspects, features and embodiments equally apply to other configurations. The AIMM 100 includes a tuner 110 that includes a matching circuit with one or more tunable elements or components. An exemplary embodiment of a tuner includes tunable capacitances and more specifically, two tunable capacitances, but it will be appreciated that the present invention can be applied to a wide variety of tunable impedance matching circuits. Operating in conjunction with sensor 127, a first detector 120 is used to detect the forward transmit power and a second detector 125 is used to detect the reflected transmit power. These values are measured in order to determine the transmitter return loss (i.e., TxRL=20 Log|S11|) where S11 is known by those skilled in the art to be the ratio between the reflected and incident power on port 1. The environment may further include a high-voltage ASIC (HV-ASIC) 130 containing a DC/DC converter and at least two DACs to generate the high voltage bias signals 132 and 134 required to control the tunable components. A micro-controller, microprocessor or other processing unit (PU) 140 receives output signals from the forward detector 120 and the reflected detector 125 and can calculate the reflected loss of the transmitted signal and thus, characterize the impedance matching of the circuit. Not illustrated, the PU 140 also interfaces or includes one or more memory elements including, but not limited to various forms of volatile and non-volatile memory. For instance, the PU may periodically write values to memory and read values from memory, such as settings for the variable components in the AIMM.

FIG. 2 is a circuit diagram illustrating further details of an exemplary matching circuit 200 that could be included in the AIMM 100 for an exemplary embodiment of the present invention. The illustrated matching circuit 200 includes a first tunable capacitance PTC1, a first impedance L1, a second impedance L2 and a second tunable capacitance PTC2 where PTC is a Paratek Tunable Capacitor. The first tunable capacitance PTC1 is coupled to ground on one end and to the output of a transceiver on the other end. The node of PTC1 that is coupled to the transceiver is also connected to a first end of the first impedance L1. The second impedance L2 is connected between the second end of the first impedance L1 and ground. The second end of the first impedance L1 is also coupled to a first end of the second tunable capacitance PTC2. The second end of the second tunable capacitance PTC2 is then coupled to an antenna 210. The tunable capacitances can be tuned over a range such as 0.3 to 1 times a nominal value C. For instance, if the nominal value of the tunable capacitance is 5 pF, the tunable range would be from 1.5 to 5 pF. In an exemplary embodiment of the present invention, PTC1 has a nominal capacitance of 5 pf and is tunable over the 0.3 to 1 times range, the first impedance L1 as a value of 3.1 nH, and the second impedance L2 has a value of 2.4 nH and the second tunable capacitance PTC2 has a nominal value of 20 pF and can be tuned over a range of 0.3 to 1 times the nominal value. It will be appreciated that the tunable capacitances in the illustrated embodiment could be tuned oar adjusted over their ranges in an effort to optimize the matching characteristics of the AIMM under various operating conditions. Thus, under various use conditions, operating environments and at various frequencies of operation, the tunable capacitances can be adjusted to optimize performance or attain a desired level of performance.

FIG. 3 is a flow diagram illustrating the general steps taken in an exemplary embodiment of the present invention. The basic flow of the algorithm 300 initially includes measuring the performance parameters or metrics 310 used as feedback pertaining to the performance of the AIMM or the impedance match between a transceiver and an antenna. The performance metrics utilized may vary over embodiments of the present invention, over various usage scenarios, over technology being utilized (i.e. FDM, TDM, etc.), based on system settings and/or carrier requirements, etc. For instance, in an exemplary embodiment of the present invention, the performance metrics include one or more of the following transmitter related metrics: the transmitter return loss, output power, current drain, and transmitter linearity.

Next, a current figure of merit (FOM) is calculated 320. The current FOM is based on the one or more performance metrics, as well as other criteria. The current FOM is then compared to a target FOM 325. The target FOM is the optimal or desired performance requirements or objective for the system. As such, the target FOM can be defined by a weighted combination of any measurable or predictable metrics. For instance, if it is desired to maximize the efficiency of the transmitter, the target FOM can be defined to result in tuning the matching network accordingly. Thus, depending on the goal or objective, the target FOM can be defined to tune the matching network to achieve particular goals or objectives. As a non-limiting example, the objectives may focus on total radiated power (TRP), total isotropic sensitivity (TIS), efficiency and linearity. Furthermore, the target FOM may be significantly different for a TDM system and an FDM system. It should be understood that the target FOM may be calculated or selected on the fly based on various operating conditions, prior measurements, and modes of operation or, the target FOM could be determined at design time and hard-coded into the AIMM 100.

If it is determined that the current FOM is not equal to the target FOM, or at least within a threshold value of the target FOM 330, new tuning values for the AIMM 100 are calculated or selected 335. However, if the current FOM is equal to or within the defined threshold, then processing continues by once again measuring the performance metrics 310 and repeating the process. Finally, if the current FOM needs to be adjusted towards the target FOM, the AIMM 100 is adjusted with the new tuning values in an effort to attain or achieve operation at the target FOM 340. In some embodiments, this new tuning value may also be stored as a new default tuning value of the transmitter at the given state of operation. For instance, in one embodiment, a single default value can be used for all situations, and as such, the latest tuning values could be stored in the variable location. In other embodiments, a default tuning state may be maintained for a variety of operational states, such as band of operation, use case scenario (i.e., hand held, antenna up/down, slider in/out, etc.) and depending on the current operational state, the new tuning values may be stored into the appropriate default variable.

In one exemplary embodiment, the AIMM 100 is adjusted by tuning one or more of the tunable components 340, measuring the new FOM (i.e., based on the transmitter reflected loss) 320-330, and re-adjusting or retuning the AIMM 100 accordingly 335-340 in a continuous loop. This process is referred to as walking the matching circuit because is moves the circuit from a non-matched state towards a matched state one step at a time. This process is continued or repeated to attain and/or maintain performance at the target FOM. Thus, the process identified by steps 310 to 340 can be repeated periodically, a periodically, as needed, or otherwise. The looping is beneficial because even if performance at the target FOM is attained, adjustments may be necessary as the mode of operation (such as usage conditions) of the device change and/or the performance of the transmitter, the antenna and the matching circuitry change over time. In other embodiments, the tunable components can be set based on look-up tables or a combination of look-up tables and performing fine-tuning adjustments. For instance, the step of calculating the AIMM tuning values 335 may involve accessing initial values from a look-up table and then, on subsequent loops through the process, fine tuning the values of the components in the AIMM 100.

In an exemplary embodiment of the present invention operating within a TDM environment, the AIMM 100 can be adjusted to optimize the operation of the transmitter during the transmit time slot. In such an embodiment, the performance metric may simply be the transmitter return loss. In addition, the target FOM in such an embodiment may also simply be a function of the transmitter return loss. In this exemplary embodiment, the AIMM 100 can be tuned to minimize the FOM or the transmitter return loss.

More particularly, for the circuit illustrated in FIG. 2, this embodiment of the present invention can operate to tune the values of PTC1 and PTC2 to minimize the transmitter return loss during the transmit time slot. For this particular example, the algorithm of FIG. 3 includes measuring the transmitter return loss, calculating adjustment values for PTC1 and PTC2 to optimize a FOM that is a function of the transmitter return loss, tuning the AIMM 100 by adjusting the values of PTC1 and PTC2 and then repeating the process.

The adjustment values for PTC1 and PTC2 can be determined in a variety of manners. For instance, in one embodiment of the invention the values may be stored in memory for various transmitter frequencies and usage scenarios. In other embodiments, the values may be heuristically determined on the fly by making adjustments to the tuning circuit, observing the effect on the transmitter return loss, and compensating accordingly. In yet another embodiment, a combination of a look-up table combined with heuristically determined fine tuning can be used to adjust the AIMM 100.

During the receiver time slot, the AIMM 100 can be readjusted to optimize or improve the performance of the receiver. Although, similar to the adjustments during the transmit time slot, particular performance parameters may be measured and used to calculate a current FOM, as previously mentioned it is difficult to measure such performance parameters for the receiver. As such, an exemplary embodiment of the present invention operates to apply a translation to the tuning values of the AIMM 100 derived at during the transmitter time slot, to improve the performance during the receive time slot. During the design of the transmitter and receiver circuitry, the characteristics of performance between the transmitter operation and receiver operation can be characterized. This characterization can then be used to identify an appropriate translation to be applied. The translation may be selected as a single value that is applicable for all operational states and use cases or, individual values can be determined for various operational states and use cases.

FIG. 4 is a plot of the transmitter reflection losses for four operating frequencies of a transceiver. The contours show the increasing magnitude of the reflection loss in 1 dB increments. For instance, in FIG. 4A, the inside contour for the transmitter 406 is 20 dB and the bolded contour is 404 14 dB. Obviously, operation at the center of the contours 402 is optimal during transmitter operation. In the illustrated example, it is apparent that simply by adjusting the value of PTC2 by adding an offset, significant performance improvements can be achieved in the receiver time slot by moving the operation towards point 412. The translation varies depending on a variety of circumstances and modes of operation including the frequency of operation, and similarly, may vary based on usage of the device housing the circuitry. In the illustrated example, the performance is determined to be greatly improved for the receiver time slot if the value of PTC2 for receiver operation is adjusted to be 0.6 times the value of PTC2 used for the optimal transmitter setting and the value of PTC1 remains the same. This is true for each of the illustrated cases except at the 915 MHz/960 MHz operational state. At 960 MHz, it is apparent that significant receiver improvement can be realized by also adjusting the value of PTC1 from its transmitter value. In the illustrated example, by examining the characteristics of the circuitry it can be empirically derived that a suitable equation for operation of the receiver at 960 MHz is:
PTC1_Rx=PTC1_Tx+1−1.8*PTC2_Tx.

It should be noted that this equation is only a non-limiting example of an equation that could be used for a particular circuit under particular operating conditions and the present invention is not limited to utilization of this particular equation.

FIG. 5 is a flow diagram illustrating the steps involved in an exemplary embodiment of the present invention operating in a TDM environment. During the transmitter time slot, the AIMM algorithm presented in FIG. 3, or some other suitable algorithm, can be applied on a continual basis to move operation of the transmitter towards the target FOM. However, when the receive time slot is activated 505, the AIMM should be adjusted to match for the receiver frequency. The adjustment to the receiver mode of operation may initially involve determining the current operating conditions of the device 510. Based on the current operating conditions, a translation for tuning of the various circuits in the AIMM 100 are identified 520. For instance, various states, components or conditions can be sensed and analyzed to determine or detect a current state or a current use case for the device. Based on this information, a particular translation value or function may be retrieved and applied. It should also be appreciated that such translations can be determined during the design phase and loaded into the device. Finally, the translations are applied to the AIMM 100 530. When operation returns to the transmitter time slot 535, the AIMM algorithm again takes over to optimize operation based on the target FOM.

It should be understood that the translation applied to tuning of the AIMM 100 during the receiver time slot is based on the particular circuit and device and can be determined during design or even on an individual basis during manufacturing and testing. As such, the specific translations identified herein are for illustrative purposes only and should not be construed to limit the operation of the present invention.

Thus, for TDM systems, embodiments of the present invention operate to optimize operation of a device by tuning the matching circuit for an antenna to optimize operation based on a target FOM. During the receiver time slot, a translation is applied to the tuned components to improve receiver performance. The target FOM can be based on a variety of performance metrics and a typical such metric is the reflection loss of the transmitter. The values for the tuned components can be set based on operational conditions and using a look-up table, can be initially set by using such a look-up table and then heuristically fine tuned, or may be heuristically determined on the fly during operation. The translations applied during the receiver operation are determined empirically based on the design of the circuitry and/or testing and measurements of the operation of the circuit. However, a unique aspect of the present invention is tuning of the matching circuit during transmit mode and based on non-receiver related metrics and then retuning the circuit during receive mode operation based on a translation to optimize or attain a desired level of receiver operation.

In an exemplary embodiment of the present invention operating within an FDM environment, the AIMM 100 can be adjusted to so that the matching characteristics represent a compromise between optimal transmitter and receiver operation. Several techniques can be applied to achieve this compromise. In one technique, the translation applied in the TDM example could be modified to adjust the AIMM 100 as a compromise between the optimal transmit and receive settings. For instance, in the example illustrated in FIG. 2, the value of PTC1 and PTC2 can be determined and adjusted periodically, similar to TDM operation (even though such action would temporarily have an adverse effect on the receiver). Then, a translation could be applied to the values of PTC1 and PTC2 for the majority of the operation time. For instance, in the TDM example shown in FIG. 4, the transmitter values were adjusted by multiplying the PTC2 value by 0.6 in three modes of operation and using the above-identified equation during a forth mode of operation. This same scheme could be used in the FDM mode of operation however, the scaling factor would be different to obtain operation that is compromised between the optimal transmitter setting and optimal receiver setting. For example, multiplying the PTC2 value by 0.8 could attain an acceptable compromise.

However, another technique of an embodiment of the present invention is to apply an algorithm that operates to attain a target FOM that is based on one or more transmitter related metrics (such as return loss) and the values of the adjustable components in the AIMM. Advantageously, this aspect of the present invention continuously attempts to maintain a compromised state of operation that keeps the operation of the transmitter and the receiver at a particular target FOM that represents a compromise performance metric level.

In the particular example illustrated in FIG. 2, such an algorithm could be based on a target FOM that is an expression consisting of the transmitter return loss and the values of PTC1 and PTC2. Because the algorithm is not operating to minimize the transmitter return loss in this embodiment of an FDM system, a compromised value is specified. For instance, a specific target transmitter return loss can be pursued for both transmitter and receiver operation by tuning the AIMM based on a FOM that is not only a function of the return loss, but also a function of the values of PTC1 and PTC2 that will encourage operation at a specific level. The target FOM is attained when the actual transmitter return loss is equal to the target transmitter return loss and, specified preferences for PTC1 and PTC2 are satisfied. The preferences illustrated are for the value of PTC1 to be the highest possible value and the value of PTC2 to be the lowest possible value while maintaining the transmit return loss at the target value and satisfying the PTC1 and PTC2 preferences.

FIG. 6 is a return loss contour diagram in the PTC plane for a particular frequency (i.e., 825 MHz/870 MHz operation). Obviously, optimal operation in an FDM system cannot typically be attained because the settings for optimal transmitter operation most likely do not coincide with those for optimal receiver operation. As such, a compromise is typically selected. For instance, a compromise may include operating the transmitter at a target return loss value of −12 dB and at a point at which the transmitter −12 dB contour is closest to a desired receiver contour (i.e., −12 dB).

The operational goal of the system is to attempt to maintain the matching circuit at a point where the operational metrics for the transmitter are at a target value (eg. −12 dB) and the estimated desired receiver operation is most proximate. In an exemplary embodiment of the present invention, an equation used to express the target FOM for such an arrangement can be stated as follows:
Target FOM=f(Tx_RL,TX_RL_Target)+f(PTC2,PTC1)
Where: TX_RL is the measure transmitter return loss
TX_RL_Target is the targeted transmitter return loss

In an exemplary embodiment suitable for the circuit provided in FIG. 2, the FOM may be expressed as:
FOM=(Tx_RL−Tx_RL_Target)+C2*PTC2−C1*PTC1), where,
C1 and C2 are preference constants or scaled values, and
if Tx_RL>Tx_RL_Target then Tx_RL=Tx_RL_Target.

In operation, exemplary embodiments of the present invention optimize the transmitter based on the target reflected loss to attain operation on the desired contour 610 (as shown in FIG. 6) and also adjusts the values of PTC1 and PTC2 to attain operation at the desired location 630 (or minimum FOM) on the contour. The portion of the FOM equation including the TxRL and TX_RL_Target values ensures operation on the targeted RL contour 610 (i.e., the −12 db RL contour). By observing the contour 610, it is quite apparent that not all points on the target reflected loss contour have the same value for the PTC1 and PTC2. Because of this, the values of PTC1 and PTC2 can be incorporated into the target FOM equation to force or encourage operation at a particular location on the reflected loss contour. In the illustrated example, the target FOM is the point at which the reflected loss contour is closest to the expected same valued reflected loss contour for the receiver. However, it will be appreciated that other performance goals may also be sought and the present invention is not limited to this particular example. For instance, in other embodiments, the target FOM may be selected to encourage operation at a mid-point between optimal transmitter performance and expected optimal receiver performance. In yet another embodiment, the target FOM may be selected to encourage operation at a point that is mid-point between a desired transmitter metric and an estimated or measured equivalent for the receiver metric.

In the provided example illustrated in FIG. 6, the optimum, compromised or desired point on the target contour is the point that minimizes the value of PTC2 and maximizes the value of PTC1 in accordance with the equation C2*PTC2-C1*PTC1. Thus, the portion of the expression including PTC1 and PTC2 ensures that operation is at a particular location on the contour that is desired—namely on the lower portion of the contour and closest to the RX_RL contour 620. In general, the algorithm operates to optimize the current FOM or, more particularly in the illustrated embodiment, to minimize the expression of C2*PTC2−C1*PTC1 as long as the desired TX_RL parameter is also met. It should be appreciated that the details associated with this example are associated with a specific circuit design and a wide variety of relationships between the adjustable components of the AIMM would apply on a circuit by circuit basis and as such, the present invention is not limited to this specific example.

Another embodiment of the present invention may take into consideration historical performance of the tunable components as well as current values. As an example, as the tunable components are adjusted, changes in the current FOM will occur in a particular direction (i.e., better or worse). As an example, if the AIMM adjustments 26 result in the current FOM falling on the top portion of a desired performance contour, making a particular adjustment may result in making the current FOM worse or better. If the adjustment was known to cause a certain result when the current FOM is located on the bottom of the contour and this time, the opposite result occurs, then this knowledge can help identify where the current FOM is located on the contour. Thus, knowing this information can be used in combination with the operation metric to attain the operation at the target FOM. For instance, the target FOM may be a function of the operational metrics, the current states of the tunable components, and the knowledge of previous results from adjusting the tunable components.

Stated another way, when a current FOM is calculated, the adjustments to reach the target FOM may take into consideration past reactions to previous adjustments. Thus, the adjustment to the tunable components may be a function of the FOM associated with a current setting and, the change in the current FOM resulting from previous changes to the tunable components.

In another embodiment of the present invention operating in an FDM environment, the FOM may be optimized similar to operation in the TDM environment. For example, the FOM may be a function of the transmitter reflected loss metric and the system may function to optimize the FOM based on this metric. Once optimized, the tunable components can be adjusted based on a predetermined translation to move the FOM from the optimized for the transmitter position to a position that is somewhere between the optimal transmitter setting and the optimal receiver setting.

FIG. 7 is a flow diagram illustrating the steps involved in an exemplary embodiment of the present invention in obtaining the preference values for PTC1 and PTC2. Initially, the process 700 involves plotting of the return loss contours for the various modes of operation, or a reasonable subset thereof 710. FIG. 6 is an example of such a plot generated as a result of performing this step. Next, the compromised tuning location is identified 720. As previously mentioned, a variety of factors may be weighed to determine the compromised tuning location and one example, as illustrated in FIG. 6, is the point at which a target reflected loss for the transmitter is the most proximate to a target reflected loss for the receiver. In a typical embodiment, this is the point at which the target transmitter and receiver contours at the desired reflected loss are closest to each other and nearly parallel. Once the compromised location is determined, the preference values can be characterized 730. For instance, in the example in FIG. 6, by drawing a perpendicular line between the two contours and passing through the compromised location, the slope and hence the preferences can be identified. These preference values can then be determined and then applied across the broad spectrum of frequencies and usage scenarios 740.

It should be appreciated that the values of C1 and C2 are constants and can vary among embodiments of the invention, as well as among devices employing the invention. As such, the values are determined empirically as described above. In an exemplary embodiment, the values of C1 and C2 are 0.7 and 2 respectively for a given circuit and a given antenna, given mode of operation, etc. Thus, any given set of constants are determined empirically and only apply to a specific antenna design, circuit and mode of operation and, although the use of these specific values may in and of itself be considered novel, the present invention is not limited to the particular expression. In fact, depending on particular goals, design criteria, operational requirements, etc. different values may be required to attain the compromised performance. It will also be appreciated that in various embodiments, it may be desired to have a different targeted reflection loss for the transmitter than for the receiver.

In another embodiment of the present invention, rather than analyzing the transmitter reflected power as the performance metric, the reflection coefficient vector may be measured. In this embodiment, the phase information of the reflection coefficient may be included within the FOM. For example, FIG. 8 is a contour plot showing the magnitude and the phase of the reflection coefficient. The preferred point of operation 830 is shown as falling on the −12 dB contour 810 and at a phase of 45 degrees. In such an embodiment, the components of the matching circuit of the AIMM 100 can be adjusted to meet a reflected loss value that falls on the −12 db contour and that also approaches the specific point on the contour—namely at the point where the reflection coefficient differs by 45 degrees.

As mentioned, mobile and transportable transceivers are subjected to a variety of use cases. For instance, a typical cellular telephone could be operated in various scenarios including speaker phone mode, ear budded, with the antenna in the up position or the down position, in the user's hand, holster, pocket, with a slider closed or extended, in a holster or out of a holster, etc. All of these scenarios, as well as a variety of other environmental circumstances can drastically alter the matching characteristics of the cellular telephone's antenna circuitry. As such, not only do the various embodiments of the present invention operate to tune the matching circuitry based on the operational frequency, but in addition, adjust the matching characteristics based on changes in the modes of operation. Advantageously, this greatly improves the performance of the device without requiring separate matching circuitry for the various modes of operation of the device. Thus, it will be appreciated that various other parameters can be monitored to identify various use cases and then adjustments to the tuning circuitry can be immediately deployed followed by fine tuning adjustments to optimize the FOM. The other parameters in which the embodiments of the present invention may function are referred to as modes of operation. The various modes of operation include the use cases as previously described, along with operating environments, bands of operation, channel frequencies, modulation formats and schemes, and physical environments. Thus, the various embodiments of the present invention may make changes, select default values, calculate adjustment values, etc., all as a function of one or more of the modes of operation.

One embodiment of the present invention may maintain a set of initial starting values based on the various use cases and operational environments. For instance, each use case may include a default value. Upon detection or activation of the device in a new use case, the default value is obtained from memory and the components in the AIMM are tuned accordingly. From that point on, the adjustment algorithm can then commence fine tuning of the operation. As previously mentioned, each time the target FOM is attained for a particular use case, the new values may be written into the default location as the new default values. Thus, every time the operational state of the device changes, such as changing between bands of operation etc., the default values are obtained and applied, and then adjustments can resume or, operation can simply be held at the default value.

Numerous specific details have now been set forth to provide a thorough understanding of the invention. However, it will be understood by those skilled in the art that the present invention may be practiced without these specific details. In other instances, well-known methods, procedures, components and circuits have not been described in detail so as not to obscure the present invention.

Unless specifically stated otherwise, as apparent from the description, it is appreciated that throughout the specification discussions that different electronic devices could be used to create a variable tuner network. The embodiments used in the examples discussed were specific to variable capacitor devices, however variable inductors, or other tunable networks, built out of elements such as Micro-Electro-Mechanical Systems (MEMS) and/or other tunable variable impedance networks could be used in such an AIMM system.

Unless specifically stated otherwise, as apparent from the description, it is appreciated that throughout the specification discussions utilizing terms such as “processing,” “computing,” “calculating,” “determining,” or the like, refer to the action and/or processes of a microprocessor, microcontroller, computer or computing system, or similar electronic computing device, that manipulate and/or transform data represented as physical, such as electronic, quantities within the computing system's registers and/or memories into other data similarly represented as physical quantities within the computing system's memories, registers or other such information storage, transmission or display devices.

Embodiments of the present invention may include apparatuses for performing the operations herein. An apparatus may be specially constructed for the desired purposes, or it may comprise a general purpose computing device selectively activated or reconfigured by a program stored in the device. Such a program may be stored on a storage medium, such as, but not limited to, any type of disk including floppy disks, optical disks, compact disc read only memories (CD-ROMs), magnetic-optical disks, read-only memories (ROMs), random access memories (RAMs), electrically programmable read-only memories (EPROMs), electrically erasable and programmable read only memories (EEPROMs), magnetic or optical cards, or any other type of media suitable for storing electronic instructions, and capable of being coupled to a system bus for a computing device.

The processes presented herein are not inherently related to any particular computing device or other apparatus. Various general purpose systems may be used with programs in accordance with the teachings herein, or it may prove convenient to construct a more specialized apparatus to perform the desired method. The desired structure for a variety of these systems will appear from the description below. In addition, embodiments of the present invention are not described with reference to any particular programming language. It will be appreciated that a variety of programming languages may be used to implement the teachings of the invention as described herein. In addition, it should be understood that operations, capabilities, and features described herein may be implemented with any combination of hardware (discrete or integrated circuits) and software.

Use of the terms “coupled” and “connected,” along with their derivatives, may be used. It should be understood that these terms are not intended as synonyms for each other. Rather, in particular embodiments, “connected” may be used to indicate that two or more elements are in direct physical or electrical contact with each other. “Coupled” may be used to indicated that two or more elements are in either direct or indirect (with other intervening elements between them) physical or electrical contact with each other, and/or that the two or more elements co-operate or interact with each other (e.g. as in a cause an effect relationship).

In the description and claims of the present application, each of the verbs, “comprise,” “include,” and “have”, and conjugates thereof, are used to indicate that the object or objects of the verb are not necessarily a complete listing of members, components, elements, or parts of the subject or subjects of the verb.

The present invention has been described using detailed descriptions of embodiments thereof that are provided by way of example and are not intended to limit the scope of the invention. The described embodiments comprise different features, not all of which are required in all embodiments of the invention. Some embodiments of the present invention utilize only some of the features or possible combinations of the features. Variations of embodiments of the present invention that are described and embodiments of the present invention comprising different combinations of features noted in the described embodiments will occur to persons of the art.

It will be appreciated by persons skilled in the art that the present invention is not limited by what has been particularly shown and described herein above. Rather the scope of the invention is defined by the claims that follow.

Claims

1. A method comprising:

obtaining, by a processor of a communication device, an operational metric for a transceiver of the communication device;
identifying a desired transmitter performance and a desired receiver performance;
determining, by the processor, a target figure of merit based on a compromise between the desired transmitter performance and the desired receiver performance;
determining, by the processor, a current figure of merit based on the operational metric;
comparing, by the processor, the current figure of merit to the target figure of merit; and
adjusting, by the processor, a variable reactance component of an impedance matching circuit a variable tuner network operably coupled with an antenna of the communication device, the adjusting of the variable reactance component being performed based on the comparing of the current and the target figures of merit, wherein the obtaining of the operational metric is during a transmit mode of the transceiver of the communication device, wherein the variable reactance component is adjusted without utilizing operational metrics measured during a receive mode of the communication device.

2. The method of claim 1, wherein the obtaining of the operational metric is during a transmit mode of the transceiver, wherein the variable reactance component is adjusted without utilizing operational metrics measured during a receive mode of the communication device.

3. The method of claim 1, comprising communicating, by the communication device, utilizing frequency division multiplexing.

4. The method of claim 1, wherein the determining of the target figure of merit includes selecting a mid-point between the desired transmitter performance and the desired receiver performance.

5. The method of claim 1, wherein the determining of the current figure of merit is based on known parameters associated with the variable reactance component and is not based on phase information.

6. The method of claim 1, comprising:

storing a tuning value based on the adjusting of the variable reactance component; and
utilizing the tuning value as a default value for subsequent tuning of the antenna.

7. The method of claim 6, comprising:

determining an operational state of the communication device; and
utilizing information associated with the operational state as a default value for subsequent tuning of the antenna.

8. The method of claim 7, wherein the operational state comprises a use case scenario selected from the group consisting essentially of hand held operation, antenna position and slider position.

9. The method of claim 1, wherein the compromise between the desired transmitter performance and the desired receiver performance is based on an evaluation of total radiated power, isotropic power or a combination thereof.

10. The method of claim 1, wherein the compromise between the desired transmitter performance and the desired receiver performance is based on an evaluation of total isotropic sensitivity a type of communication service.

11. The method of claim 1, wherein the compromise between the desired transmitter performance and the desired receiver performance is based on an evaluation of transmitter linearity.

12. The method of claim 1, wherein the compromise between the desired transmitter performance and the desired receiver performance is based on an evaluation of transmitter efficiency.

13. A communication device comprising:

an antenna;
a transceiver;
an impedance matching a variable tuner network coupled with the antenna and the transceiver, wherein the impedance matching variable tuner network includes a variable reactance component;
a memory to store computer instructions; and
a controller coupled with the memory and the impedance matching variable tuner network, wherein the controller, responsive to executing the computer instructions, performs operations comprising: obtaining an operational metric associated with the transceiver communication device; identifying a desired transmitter performance and a desired receiver performance; determining a target figure of merit based on a compromise between the desired transmitter performance and the desired receiver performance; determining a current figure of merit based on the operational metric; and adjusting the variable reactance component of the impedance matching circuit variable tuner network based on a comparison of the current figure of merit with and the target figure of merit, wherein the obtaining of the operational metric is during a transmit mode of the transceiver, and wherein the variable reactance component is adjusted without utilizing operational metrics measured during a receive mode of the communication device.

14. The communication device of claim 13, further comprising a transceiver, wherein the variable reactance component includes a voltage tunable capacitor, and wherein the operations of the controller further comprise:

determining a use case for the communication device; and
performing an initial adjustment of the voltage tunable capacitor based on the use case without utilizing any operational metrics associated with the transceiver, wherein the initial adjustment of the voltage tunable capacitor is performed prior to the adjusting based on the comparison of the current figure of merit with the target figure of merit.

15. The communication device of claim 13, wherein the variable reactance component includes a Micro-Electro-Mechanical Systems (MEMS) variable reactance component.

16. The communication device of claim 13, wherein the operations of the controller further comprise:

storing a tuning value based on the adjusting of the variable reactance component; and
utilizing the tuning value as a default value for subsequent tuning of the antenna.

17. The communication device of claim 13, wherein the obtaining of the operational metric is during a transmit mode of the transceiver, and wherein the variable reactance component is adjusted without utilizing operational metrics measured during a receive mode of the communication device.

18. The communication device of claim 13, wherein the adjusting of the variable reactance component is associated with a communication session that utilizes frequency division multiplexing.

19. A method comprising:

obtaining an operational metric for a transceiver of a communication device;
determining a target figure of merit based on transceiver performance of the communication device;
determining a current figure of merit based on the operational metric, wherein the determining of the target figure of merit is not based on phase information;
comparing the current figure of merit to the target figure of merit to determine a figure of merit comparison; and
adjusting, by a processor of the communication device, a variable reactance component of an impedance matching circuit a variable tuner network operably coupled with an antenna of the communication device, the adjusting of the variable reactance component being performed based on the figure current and target figures of merit comparison and based on previous tuning results associated with previous adjusting of the variable reactance component the variable tuner network, wherein the obtaining of the operational metric is during a transmit mode of the transceiver, and wherein the variable reactance component is adjusted without utilizing operational metrics measured during a receive mode of the communication device.

20. The method of claim 19, comprising monitoring the previous tuning results by determining a change in the current figure of merit based on different reactance values for the variable reactance component.

21. The method of claim 19, wherein the operational metric comprises a return loss.

22. The method of claim 19, wherein the variable reactance component includes at least one of a Micro-Electro-Mechanical Systems (MEMS) variable reactance component and a voltage tunable capacitor.

23. The method of claim 19, wherein the current figure of merit, the target figure of merit or both is according to a vector measurement of a transmission reflection coefficient.

24. The method of claim 1, wherein the adjusting of the variable reactance component is based on tuning values stored in a lookup table.

25. A communication device comprising:

an antenna;
a transceiver;
a variable tuner network coupled with the antenna;
a memory that stores computer instructions; and a controller coupled with the memory and the variable tuner network, wherein the controller, responsive to executing the computer instructions, performs operations comprising: obtaining a non-receiver operational metric; identifying a first desired performance of the communication device; identifying a second desired performance of the communication device; determining a target figure of merit based on a compromise between the first desired performance and the second desired performance; determining a current figure of merit based on the non-receiver operational metric; and adjusting a variable reactance of the variable tuner network based on the current figure of merit and the target figure of merit, wherein the obtaining of the operational metric is during a transmit mode of the transceiver, and wherein the variable reactance component is adjusted without utilizing operational metrics measured during a receive mode of the communication device.

26. The communication device of claim 25, wherein the target figure of merit is stored in a lookup table.

27. The communication device of claim 25, wherein the first desired performance is associated with a first component of the communication device, and wherein the second desired performance is associated with a second component of the communication device.

28. The communication device of claim 25, wherein the variable tuner network includes a Micro-Electro-Mechanical Systems (MEMS) variable reactance component.

29. The communication device of claim 25, wherein the variable tuner network includes a voltage tunable capacitor.

30. A communication device comprising:

an antenna;
a transceiver;
a variable tuner network coupled with the antenna;
a memory that stores computer instructions; and
a controller coupled with the memory and the variable tuner network, wherein the controller, responsive to executing the computer instructions, performs operations comprising: obtaining an operational metric for communications of a communication device; determining a target figure of merit based on communications performance of the communication device; determining a current figure of merit based on the operational metric, wherein the determining of the target figure of merit is not based on phase information; and adjusting the variable tuner network based on the current and target figures of merit, wherein the obtaining of the operational metric is during a transmit mode of the transceiver, and wherein the variable tuner network is adjusted without utilizing operational metrics measured during a receive mode of the communication device.

31. The communication device of claim 30, wherein the adjusting of the variable tuner network is further based on previous tuning results associated with previous adjusting of the variable tuner network.

32. The communication device of claim 30, wherein the operational metric comprises a return loss.

33. The communication device of claim 30, wherein the communications performance is associated with total radiated power, total isotropic sensitivity, linearity or a combination thereof.

34. The communication device of claim 30, wherein the variable tuner network includes a Micro-Electro-Mechanical Systems (MEMS) variable reactance component.

35. The communication device of claim 30, wherein the variable tuner network includes a voltage tunable capacitor.

Referenced Cited
U.S. Patent Documents
2745067 May 1956 True
3117279 January 1964 Ludvigson
3160832 December 1964 Beitman
3390337 June 1968 Beitman
3443231 May 1969 Roza
3509500 April 1970 McNair
3571716 March 1971 Hill
3590385 June 1971 Sabo
3601717 August 1971 Kuecken
3742279 June 1973 Kupsky
3749491 July 1973 Maxfield et al.
3794941 February 1974 Templin
3919644 November 1975 Smolka
3990024 November 2, 1976 Hou
3995237 November 30, 1976 Brunner
4186359 January 29, 1980 Kaegebein
4201960 May 6, 1980 Skutta
4227256 October 7, 1980 O'Keefe
4383441 May 17, 1983 Willis
4476578 October 9, 1984 Gaudin
4493112 January 8, 1985 Bruene
4509019 April 2, 1985 Banu et al.
4777490 October 11, 1988 Sharma
4799066 January 17, 1989 Deacon
4965607 October 23, 1990 Wilkins
4970478 November 13, 1990 Townley et al.
4980656 December 25, 1990 Duffalo
5032805 July 16, 1991 Elmer
5136478 August 4, 1992 Bruder
5142255 August 25, 1992 Chang
5177670 January 5, 1993 Shinohara
5195045 March 16, 1993 Keane
5200826 April 6, 1993 Seong
5212463 May 18, 1993 Babbitt
5215463 June 1, 1993 Marshall et al.
5216392 June 1, 1993 Fraser et al.
5230091 July 20, 1993 Vaisanen et al.
5243358 September 7, 1993 Sanford
5258728 November 2, 1993 Taniyoshi
5276912 January 4, 1994 Siwiak
5301358 April 5, 1994 Gaskill
5307033 April 26, 1994 Koscica
5310358 May 10, 1994 Johnson
5312790 May 17, 1994 Sengupta
5334958 August 2, 1994 Babbitt
5361403 November 1, 1994 Dent
5371473 December 6, 1994 Trinh
5409889 April 25, 1995 Das
5427988 June 27, 1995 Sengupta
5430417 July 4, 1995 Martin
5446447 August 29, 1995 Carney
5448252 September 5, 1995 Ali
5451567 September 19, 1995 Das
5451914 September 19, 1995 Stengel
5457394 October 10, 1995 McEwan
5472935 December 5, 1995 Yandrofski
5479139 December 26, 1995 Koscica
5486491 January 23, 1996 Sengupta
5496795 March 5, 1996 Das
5502372 March 26, 1996 Quan
5524281 June 4, 1996 Bradley
5548837 August 20, 1996 Hess et al.
5561086 October 1, 1996 Cygan
5561407 October 1, 1996 Koscica
5564086 October 8, 1996 Cygan
5583359 December 10, 1996 Ng et al.
5589844 December 31, 1996 Belcher et al.
5593495 January 14, 1997 Masuda
5635433 June 3, 1997 Sengupta
5635434 June 3, 1997 Sengupta
5640042 June 17, 1997 Koscica
5679624 October 21, 1997 Das
5689219 November 18, 1997 Piirainen
5693429 December 2, 1997 Sengupta
5694134 December 2, 1997 Barnes
5699071 December 16, 1997 Urakami
5721194 February 24, 1998 Yandrofski
5766697 June 16, 1998 Sengupta
5777581 July 7, 1998 Lilly
5778308 July 7, 1998 Sroka
5786727 July 28, 1998 Sigmon
5812572 September 22, 1998 King
5812943 September 22, 1998 Suzuki
5830591 November 3, 1998 Sengupta
5846893 December 8, 1998 Sengupta
5874926 February 23, 1999 Tsuru
5880635 March 9, 1999 Satoh
5886867 March 23, 1999 Chivukula
5892482 April 6, 1999 Coleman et al.
5926751 July 20, 1999 Vlahos et al.
5929717 July 27, 1999 Richardson
5940030 August 17, 1999 Hampel et al.
5963871 October 5, 1999 Zhinong
5969582 October 19, 1999 Boesch
5973568 October 26, 1999 Shapiro et al.
5982099 November 9, 1999 Barnes et al.
5990766 November 23, 1999 Zhang
6008759 December 28, 1999 Tangemann et al.
6009124 December 28, 1999 Smith
6020787 February 1, 2000 Kim
6020795 February 1, 2000 Kim
6029075 February 22, 2000 Das
6045932 April 4, 2000 Jia
6061025 May 9, 2000 Jackson
6064865 May 16, 2000 Kuo et al.
6074971 June 13, 2000 Chiu
6096127 August 1, 2000 Dimos
6100733 August 8, 2000 Dortu
6101102 August 8, 2000 Brand
6115585 September 5, 2000 Matero
6125266 September 26, 2000 Matero et al.
6133868 October 17, 2000 Butler et al.
6133883 October 17, 2000 Munson
6172385 January 9, 2001 Duncombe
6215644 April 10, 2001 Dhuler
6242989 June 5, 2001 Barber
6266528 July 24, 2001 Farzaneh
6281748 August 28, 2001 Klomsdorf et al.
6281847 August 28, 2001 Lee
6309895 October 30, 2001 Jaing
6343208 January 29, 2002 Ying
6377142 April 23, 2002 Chiu
6377217 April 23, 2002 Zhu
6377440 April 23, 2002 Zhu
6384785 May 7, 2002 Kamogawa
6404614 June 11, 2002 Zhu
6408190 June 18, 2002 Ying
6414562 July 2, 2002 Bouisse
6415562 July 9, 2002 Donaghue
6438360 August 20, 2002 Alberth, Jr. et al.
6452776 September 17, 2002 Chakravorty
6461930 October 8, 2002 Akram
6466774 October 15, 2002 Okabe
6492883 December 10, 2002 Liang
6514895 February 4, 2003 Chiu
6525630 February 25, 2003 Zhu
6531936 March 11, 2003 Chiu
6535076 March 18, 2003 Partridge
6535722 March 18, 2003 Rosen
6538603 March 25, 2003 Chen
6556102 April 29, 2003 Sengupta
6556814 April 29, 2003 Klomsdorf
6570462 May 27, 2003 Edmonson
6590468 July 8, 2003 du Toit
6590541 July 8, 2003 Schultze
6597265 July 22, 2003 Liang
6608603 August 19, 2003 Alexopoulos
6624786 September 23, 2003 Boyle
6628962 September 30, 2003 Katsura et al.
6640085 October 28, 2003 Chatzipetros
6657595 December 2, 2003 Phillips et al.
6661638 December 9, 2003 Jackson et al.
6670256 December 30, 2003 Yang
6710651 March 23, 2004 Forrester
6724611 April 20, 2004 Mosley
6724890 April 20, 2004 Bareis
6737179 May 18, 2004 Sengupta
6747522 June 8, 2004 Pietruszynski et al.
6759918 July 6, 2004 Du Toit
6765540 July 20, 2004 Toncich
6768472 July 27, 2004 Alexopoulos
6774077 August 10, 2004 Sengupta
6795712 September 21, 2004 Vakilian
6825818 November 30, 2004 Toncich
6839028 January 4, 2005 Lee
6845126 January 18, 2005 Dent
6859104 February 22, 2005 Toncich
6862432 March 1, 2005 Kim
6864757 March 8, 2005 Du Toit
6868260 March 15, 2005 Jagielski
6875655 April 5, 2005 Lin
6882245 April 19, 2005 Utsunomiya
6888714 May 3, 2005 Shaw
6905989 June 14, 2005 Ellis
6906653 June 14, 2005 Uno
6907234 June 14, 2005 Karr
6914487 July 5, 2005 Doyle et al.
6920315 July 19, 2005 Wilcox et al.
6922330 July 26, 2005 Nielsen
6943078 September 13, 2005 Zheng
6946847 September 20, 2005 Nishimori
6949442 September 27, 2005 Barth
6961368 November 1, 2005 Dent
6964296 November 15, 2005 Memory
6965837 November 15, 2005 Vintola
6987493 January 17, 2006 Chen
6993297 January 31, 2006 Smith
6999297 February 14, 2006 Klee
7009455 March 7, 2006 Toncich
7071776 July 4, 2006 Forrester
7106715 September 12, 2006 Kelton
7107033 September 12, 2006 du Toit
7113614 September 26, 2006 Rhoads
7151411 December 19, 2006 Martin
7176634 February 13, 2007 Kitamura
7176845 February 13, 2007 Fabrega-Sanchez
7180467 February 20, 2007 Fabrega-Sanchez
7218186 May 15, 2007 Chen et al.
7221327 May 22, 2007 Toncich
7298329 November 20, 2007 Diament
7299018 November 20, 2007 Van Rumpt
7312118 December 25, 2007 Kiyotoshi
7332980 February 19, 2008 Zhu
7332981 February 19, 2008 Matsuno
7339527 March 4, 2008 Sager
7369828 May 6, 2008 Shamsaifar
7426373 September 16, 2008 Clingman
7427949 September 23, 2008 Channabasappa et al.
7453405 November 18, 2008 Nishikido et al.
7468638 December 23, 2008 Tsai
7469129 December 23, 2008 Blaker et al.
7528674 May 5, 2009 Kato et al.
7531011 May 12, 2009 Yamasaki
7535080 May 19, 2009 Zeng et al.
7535312 May 19, 2009 McKinzie
7539527 May 26, 2009 Jang
7557507 July 7, 2009 Wu
7567782 July 28, 2009 Liu et al.
7596357 September 29, 2009 Nakamata
7633355 December 15, 2009 Matsuo
7642879 January 5, 2010 Matsuno
7655530 February 2, 2010 Hosking
7667663 February 23, 2010 Hsiao
7671693 March 2, 2010 Brobston et al.
7705692 April 27, 2010 Fukamachi et al.
7711337 May 4, 2010 McKinzie
7714676 May 11, 2010 McKinzie
7714678 May 11, 2010 du Toit et al.
7728693 June 1, 2010 du Toit et al.
7760699 July 20, 2010 Malik
7768400 August 3, 2010 Lawrence et al.
7786819 August 31, 2010 Ella
7795990 September 14, 2010 du Toit
7830320 November 9, 2010 Shamblin et al.
7852170 December 14, 2010 McKinzie
7856228 December 21, 2010 Lekutai et al.
7865154 January 4, 2011 Mendolia
7907094 March 15, 2011 Kakitsu et al.
7917104 March 29, 2011 Manssen et al.
7940223 May 10, 2011 Dou et al.
7949309 May 24, 2011 Rofougaran
7969257 June 28, 2011 du Toit
7983615 July 19, 2011 Bryce et al.
7991363 August 2, 2011 Greene
8008982 August 30, 2011 McKinzie
8072285 December 6, 2011 Spears
8112043 February 7, 2012 Knudsen et al.
8170510 May 1, 2012 Knudsen et al.
8190109 May 29, 2012 Ali et al.
8204446 June 19, 2012 Scheer
8213886 July 3, 2012 Blin
8217731 July 10, 2012 McKinzie et al.
8217732 July 10, 2012 McKinzie
8299867 October 30, 2012 McKinzie
8320850 November 27, 2012 Khlat
8325097 December 4, 2012 McKinzie, III et al.
8405563 March 26, 2013 McKinzie et al.
8421548 April 16, 2013 Spears et al.
8432234 April 30, 2013 Manssen et al.
8442457 May 14, 2013 Harel et al.
8454882 June 4, 2013 Chan et al.
8457569 June 4, 2013 Blin
8472888 June 25, 2013 Manssen et al.
8478344 July 2, 2013 Rofougaran et al.
8543123 September 24, 2013 Moon et al.
8543176 September 24, 2013 Daniel et al.
8558633 October 15, 2013 McKinzie, III
8564381 October 22, 2013 McKinzie
8594584 November 26, 2013 Greene et al.
8620236 December 31, 2013 Manssen et al.
8620246 December 31, 2013 McKinzie et al.
8620247 December 31, 2013 McKinzie et al.
8655286 February 18, 2014 Mendolia
8674783 March 18, 2014 Spears et al.
8680934 March 25, 2014 McKinzie et al.
8693963 April 8, 2014 du Toit et al.
8712340 April 29, 2014 Hoirup et al.
8712348 April 29, 2014 Brobston et al.
8773019 July 8, 2014 Pham et al.
8774743 July 8, 2014 Ali et al.
8787845 July 22, 2014 Manssen et al.
8803631 August 12, 2014 Greene et al.
8860525 October 14, 2014 Spears et al.
8948889 February 3, 2015 Spears et al.
8957742 February 17, 2015 Spears et al.
9026062 May 5, 2015 Greene et al.
9083405 July 14, 2015 Christoffersson et al.
9119152 August 25, 2015 Blin
9231643 January 5, 2016 Greene et al.
9374113 June 21, 2016 Manssen et al.
9379454 June 28, 2016 Rabe et al.
9406444 August 2, 2016 McKinzie et al.
9473194 October 18, 2016 Domino et al.
9698758 July 4, 2017 Spears et al.
9698858 July 4, 2017 Hoirup et al.
9742375 August 22, 2017 Manssen et al.
9762416 September 12, 2017 Mandegaran et al.
9768752 September 19, 2017 du Toit et al.
9768810 September 19, 2017 Greene et al.
9853363 December 26, 2017 Ali et al.
9935674 April 3, 2018 Hoirup et al.
20020008672 January 24, 2002 Gothard et al.
20020030566 March 14, 2002 Bozler
20020047154 April 25, 2002 Sowlati et al.
20020079982 June 27, 2002 Lafleur et al.
20020109642 August 15, 2002 Gee et al.
20020118075 August 29, 2002 Ohwada
20020145483 October 10, 2002 Bouisse
20020167963 November 14, 2002 Joa-Ng
20020183013 December 5, 2002 Auckland et al.
20020187780 December 12, 2002 Souissi
20020191703 December 19, 2002 Ling et al.
20020193088 December 19, 2002 Jung
20030060227 March 27, 2003 Sekine et al.
20030071300 April 17, 2003 Yashima
20030114124 June 19, 2003 Higuchi
20030137464 July 24, 2003 Foti et al.
20030142022 July 31, 2003 Ollikainen
20030184319 October 2, 2003 Nishimori et al.
20030193997 October 16, 2003 Dent
20030199286 October 23, 2003 du Toit
20030210203 November 13, 2003 Phillips et al.
20030210206 November 13, 2003 Phillips
20030216150 November 20, 2003 Ueda
20030232607 December 18, 2003 Le Bars
20040009754 January 15, 2004 Smith
20040090372 May 13, 2004 Nallo
20040100341 May 27, 2004 Luetzelschwab et al.
20040125027 July 1, 2004 Rubinshteyn et al.
20040127178 July 1, 2004 Kuffner
20040137950 July 15, 2004 Bolin
20040202399 October 14, 2004 Kochergin
20040204027 October 14, 2004 Park et al.
20040227176 November 18, 2004 York
20040232982 November 25, 2004 Itchitsubo et al.
20040257293 December 23, 2004 Friedrich et al.
20040263411 December 30, 2004 Fabrega-Sanchez et al.
20040264610 December 30, 2004 Marro et al.
20050007291 January 13, 2005 Fabrega-Sanchez
20050032488 February 10, 2005 Pehlke
20050032541 February 10, 2005 Wang
20050042994 February 24, 2005 Otaka
20050059362 March 17, 2005 Kalajo
20050082636 April 21, 2005 Yashima
20050083234 April 21, 2005 Poilasne et al.
20050085204 April 21, 2005 Poilasne et al.
20050093624 May 5, 2005 Forrester et al.
20050130608 June 16, 2005 Forse
20050130699 June 16, 2005 Kim
20050145987 July 7, 2005 Okuda et al.
20050208960 September 22, 2005 Hassan
20050215204 September 29, 2005 Wallace
20050227627 October 13, 2005 Cyr et al.
20050227633 October 13, 2005 Dunko
20050259011 November 24, 2005 Vance
20050260962 November 24, 2005 Nazrul et al.
20050264455 December 1, 2005 Talvitie
20050280588 December 22, 2005 Fujikawa et al.
20050282503 December 22, 2005 Onno
20060003537 January 5, 2006 Sinha
20060009165 January 12, 2006 Alles
20060022882 February 2, 2006 Gerder et al.
20060030277 February 9, 2006 Cyr et al.
20060077082 April 13, 2006 Shanks et al.
20060084392 April 20, 2006 Marholev et al.
20060099915 May 11, 2006 Laroia et al.
20060099952 May 11, 2006 Prehofer et al.
20060119511 June 8, 2006 Collinson et al.
20060148415 July 6, 2006 Hamalainen et al.
20060160501 July 20, 2006 Mendolia
20060183431 August 17, 2006 Chang et al.
20060183433 August 17, 2006 Mori et al.
20060183442 August 17, 2006 Chang et al.
20060195161 August 31, 2006 Li et al.
20060205368 September 14, 2006 Bustamante
20060209767 September 21, 2006 Chae et al.
20060223451 October 5, 2006 Posamentier
20060252391 November 9, 2006 Poilasne et al.
20060281423 December 14, 2006 Caimi
20070001924 January 4, 2007 Hirabayashi et al.
20070013483 January 18, 2007 Stewart
20070035458 February 15, 2007 Ohba
20070042725 February 22, 2007 Poilasne
20070042734 February 22, 2007 Ryu
20070063788 March 22, 2007 Zhu
20070077956 April 5, 2007 Julian et al.
20070080888 April 12, 2007 Mohamadi
20070082611 April 12, 2007 Terranova et al.
20070085609 April 19, 2007 Itkin
20070091006 April 26, 2007 Thober et al.
20070093282 April 26, 2007 Chang et al.
20070109716 May 17, 2007 Martin et al.
20070111681 May 17, 2007 Alberth et al.
20070121267 May 31, 2007 Kotani et al.
20070142011 June 21, 2007 Shatara
20070142014 June 21, 2007 Wilcox
20070149146 June 28, 2007 Hwang
20070171879 July 26, 2007 Bourque
20070182636 August 9, 2007 Carlson
20070184825 August 9, 2007 Lim et al.
20070194859 August 23, 2007 Brobston
20070197180 August 23, 2007 McKinzie et al.
20070200766 August 30, 2007 McKinzie
20070200773 August 30, 2007 Dou et al.
20070210899 September 13, 2007 Kato et al.
20070222697 September 27, 2007 Caimi et al.
20070248238 October 25, 2007 Abreu et al.
20070285326 December 13, 2007 McKinzie
20070293176 December 20, 2007 Yu
20080007478 January 10, 2008 Jung
20080018541 January 24, 2008 Pang
20080030165 February 7, 2008 Lisac et al.
20080051096 February 28, 2008 Rao et al.
20080055016 March 6, 2008 Morris, III et al.
20080055168 March 6, 2008 Massey et al.
20080081670 April 3, 2008 Rofougaran
20080090539 April 17, 2008 Thompson
20080090573 April 17, 2008 Kim et al.
20080094149 April 24, 2008 Brobston
20080106350 May 8, 2008 McKinzie
20080111748 May 15, 2008 Dunn et al.
20080122553 May 29, 2008 McKinzie
20080122723 May 29, 2008 Rofougaran
20080129612 June 5, 2008 Wang
20080158076 July 3, 2008 Walley
20080174508 July 24, 2008 Iwai et al.
20080261544 October 23, 2008 Guillaume
20080266190 October 30, 2008 Ohba et al.
20080268893 October 30, 2008 Lee et al.
20080274706 November 6, 2008 Blin
20080280570 November 13, 2008 Blin
20080285729 November 20, 2008 Glasgow et al.
20080288028 November 20, 2008 Larson et al.
20080294718 November 27, 2008 Okano
20080300027 December 4, 2008 Dou et al.
20080305749 December 11, 2008 Ben-Bassat
20080305750 December 11, 2008 Alon et al.
20080309617 December 18, 2008 Kong et al.
20090002077 January 1, 2009 Rohani et al.
20090016124 January 15, 2009 Kim
20090027286 January 29, 2009 Ohishi
20090039976 February 12, 2009 McKinzie, III
20090051604 February 26, 2009 Zhang et al.
20090051611 February 26, 2009 Shamblin et al.
20090079656 March 26, 2009 Peyla et al.
20090082017 March 26, 2009 Chang et al.
20090088093 April 2, 2009 Nentwig et al.
20090109880 April 30, 2009 Kim et al.
20090121963 May 14, 2009 Greene
20090149136 June 11, 2009 Rofougaran
20090180403 July 16, 2009 Tudosoiu
20090184879 July 23, 2009 Derneryd
20090196192 August 6, 2009 Lim et al.
20090215446 August 27, 2009 Hapsari et al.
20090231220 September 17, 2009 Zhang et al.
20090253385 October 8, 2009 Dent et al.
20090264065 October 22, 2009 Song
20090278685 November 12, 2009 Potyrailo
20090295651 December 3, 2009 Dou et al.
20090323572 December 31, 2009 Shi et al.
20090323582 December 31, 2009 Proctor et al.
20100041348 February 18, 2010 Wilcox et al.
20100053009 March 4, 2010 Rofougaran
20100060531 March 11, 2010 Rappaport
20100069011 March 18, 2010 Carrick et al.
20100073103 March 25, 2010 Spears et al.
20100085260 April 8, 2010 McKinzie
20100085884 April 8, 2010 Srinivisan et al.
20100105425 April 29, 2010 Asokan
20100107067 April 29, 2010 Vaisanen et al.
20100134215 June 3, 2010 Lee et al.
20100156552 June 24, 2010 McKinzie
20100164640 July 1, 2010 McKinzie
20100164641 July 1, 2010 McKinzie
20100201598 August 12, 2010 Lau et al.
20100214189 August 26, 2010 Kanazawa et al.
20100232474 September 16, 2010 Rofougaran
20100244576 September 30, 2010 Hillan et al.
20100277363 November 4, 2010 Kainulainen et al.
20100285836 November 11, 2010 Horihata et al.
20100302106 December 2, 2010 Knudsen et al.
20100304684 December 2, 2010 Duron et al.
20100304688 December 2, 2010 Knudsen
20100308933 December 9, 2010 See et al.
20110002080 January 6, 2011 Ranta
20110012790 January 20, 2011 Badaruzzaman
20110012792 January 20, 2011 Krenz
20110014879 January 20, 2011 Alberth et al.
20110014886 January 20, 2011 Manssen
20110019606 January 27, 2011 Umeda et al.
20110026415 February 3, 2011 Kamuf et al.
20110039504 February 17, 2011 Nguyen et al.
20110043298 February 24, 2011 McKinzie
20110043328 February 24, 2011 Bassali
20110053524 March 3, 2011 Manssen
20110063042 March 17, 2011 Mendolia
20110086600 April 14, 2011 Muhammad
20110086630 April 14, 2011 Manssen
20110102290 May 5, 2011 Milosavljevic
20110105023 May 5, 2011 Scheer et al.
20110116395 May 19, 2011 Tsuda et al.
20110116423 May 19, 2011 Rousu et al.
20110117863 May 19, 2011 Camp, Jr. et al.
20110117973 May 19, 2011 Asrani et al.
20110121079 May 26, 2011 Lawrence et al.
20110122040 May 26, 2011 Wakabayashi et al.
20110133994 June 9, 2011 Korva
20110140982 June 16, 2011 Ozden et al.
20110183628 July 28, 2011 Baker
20110183633 July 28, 2011 Ohba
20110195679 August 11, 2011 Lee et al.
20110227666 September 22, 2011 Manssen
20110237207 September 29, 2011 Bauder
20110249760 October 13, 2011 Chrisikos et al.
20110250852 October 13, 2011 Greene
20110254637 October 20, 2011 Manssen
20110254638 October 20, 2011 Manssen
20110256857 October 20, 2011 Chen et al.
20110281532 November 17, 2011 Shin et al.
20110285511 November 24, 2011 Maguire et al.
20110299438 December 8, 2011 Mikhemar
20110306310 December 15, 2011 Bai
20110309980 December 22, 2011 Ali et al.
20120039189 February 16, 2012 Suzuki et al.
20120051409 March 1, 2012 Brobston et al.
20120056689 March 8, 2012 Spears et al.
20120062431 March 15, 2012 Tikka et al.
20120075159 March 29, 2012 Chang
20120084537 April 5, 2012 Indukuru
20120094708 April 19, 2012 Park
20120099462 April 26, 2012 Yuda et al.
20120100802 April 26, 2012 Mohebbi
20120112851 May 10, 2012 Manssen
20120112852 May 10, 2012 Manssen et al.
20120112970 May 10, 2012 Caballero et al.
20120119843 May 17, 2012 du Toit et al.
20120119844 May 17, 2012 du Toit et al.
20120139810 June 7, 2012 Faraone et al.
20120154975 June 21, 2012 Oakes
20120214421 August 23, 2012 Hoirup
20120220243 August 30, 2012 Mendolia
20120243579 September 27, 2012 Premakanthan et al.
20120286586 November 15, 2012 Balm
20120293384 November 22, 2012 Knudsen et al.
20120295554 November 22, 2012 Greene
20120295555 November 22, 2012 Greene et al.
20120309332 December 6, 2012 Liao et al.
20130005277 January 3, 2013 Klomsdorf et al.
20130052967 February 28, 2013 Black et al.
20130056841 March 7, 2013 Hsieh et al.
20130076579 March 28, 2013 Zhang et al.
20130076580 March 28, 2013 Zhang et al.
20130106332 May 2, 2013 Williams et al.
20130122829 May 16, 2013 Hyvonen et al.
20130137384 May 30, 2013 Desclos et al.
20130154897 June 20, 2013 Sorensen et al.
20130182583 July 18, 2013 Siomina et al.
20130194054 August 1, 2013 Presti
20130215846 August 22, 2013 Yerrabommanahalli et al.
20130231155 September 5, 2013 Sheynman et al.
20130265912 October 10, 2013 Ikonen et al.
20130293425 November 7, 2013 Zhu et al.
20130315285 November 28, 2013 Black et al.
20140002323 January 2, 2014 Ali et al.
20140009360 January 9, 2014 Ikonen et al.
20140128032 May 8, 2014 Muthukumar
20140162572 June 12, 2014 Hirabayashi
20140210686 July 31, 2014 Ali et al.
20140287698 September 25, 2014 Ali et al.
20140366927 December 18, 2014 Lavrova et al.
20160173172 June 16, 2016 Greene
20160241276 August 18, 2016 Zhu
20160269055 September 15, 2016 Greene et al.
20160277129 September 22, 2016 Manssen
20160322991 November 3, 2016 McKinzie
20160336916 November 17, 2016 Du Toit et al.
20160352408 December 1, 2016 Greene
20160373146 December 22, 2016 Manssen et al.
20170011858 January 12, 2017 Oakes et al.
20170085244 March 23, 2017 Manssen et al.
20170197180 July 13, 2017 Wei
20170264322 September 14, 2017 Greene et al.
20170264335 September 14, 2017 Hoirup et al.
20170294712 October 12, 2017 Greene et al.
20170294891 October 12, 2017 McKinzie, III
20170353956 December 7, 2017 Carsten
20170373661 December 28, 2017 Manssen et al.
20180083657 March 22, 2018 Manssen et al.
20180109235 April 19, 2018 McKinzie et al.
20180198482 July 12, 2018 Hoirup et al.
20180262257 September 13, 2018 Greene
Foreign Patent Documents
2914562 June 2016 CA
101640949 February 2010 CN
201765685 March 2011 CN
105703797 June 2016 CN
105703797 June 2016 CN
19614655 October 1997 DE
10258805 March 2005 DE
102008050743 April 2010 DE
102009018648 October 2010 DE
0909024 April 1999 EM
0685936 June 1995 EP
0909024 April 1999 EP
1079296 February 2001 EP
1137192 September 2001 EP
1298810 April 2006 EP
20070197180 August 2007 EP
2214085 August 2010 EP
2328233 June 2011 EP
2388925 November 2011 EP
2424119 February 2012 EP
2638640 July 2014 EP
3131157 February 2017 EP
03-276901 March 1990 JP
02-077580 September 1991 JP
9321526 December 1997 JP
10209722 August 1998 JP
2000124066 April 2000 JP
2005-130441 May 2005 JP
100645526 November 2006 KR
10-0740177 July 2007 KR
2001/071846 September 2001 WO
2006/031170 March 2006 WO
2008/030165 March 2008 WO
2008133854 November 2008 WO
2009/064968 May 2009 WO
2009/108391 September 2009 WO
2009/155966 December 2009 WO
2009155966 December 2009 WO
2010028521 March 2010 WO
2010121914 October 2010 WO
2011/044592 April 2011 WO
2011/084716 July 2011 WO
2011084716 July 2011 WO
2011102143 August 2011 WO
2011/133657 October 2011 WO
WO-2011028453 October 2011 WO
2012/067622 May 2012 WO
2012067622 May 2012 WO
2012/085932 June 2012 WO
2012085932 June 2012 WO
2012112831 August 2012 WO
Other references
  • Communication pursuant to Article 94(3) EPC issued by the European Patent Office, dated Nov. 16, 2017. European Patent Application 12177197.6.
  • Communication pursuant to Article 94(3) EPC, EPO application No. 16151299.1, dated Jun. 22, 2018.
  • Canadian Office Action, Application No. 2,821,173, dated Oct. 17, 2016.
  • Extended European Search Report for 12749235.3 dated Jun. 8, 2017.
  • Canadian Office Action dated Feb. 8, 2018, application No. 2826573, 4 pages.
  • Office Action dated Nov. 7, 2018, Canadian Patent Application 2,826,573, 4 pages.
  • Communication pursuant to Article 94(3) EPC, Application No. 10822849.5, dated Oct. 11, 2017, 5 pages.
  • “China International Intellectual Property Administration”, First Office Action for CN Application No. 201510941292.3, dated Oct. 29, 2018, 6 pages.
  • “Communication pursuant to Article 94(3) EPC”, EP Application Serial No. 12750926.3, dated Mar. 16, 2018, 5 pages.
  • “European Search Report”, 16151299.1 search report, dated 2016.
  • “Extended European Search Report”, EP Application No. 16155235.1, dated May 3, 2016.
  • “Office Action Received in China Patent Application 201080045689.X”, dated Mar. 4, 2016, 6 pages.
  • “Search Report”, ROC (Taiwan) Patent Application No. 101117467, English Translation, dated Apr. 12, 2016, 1 page.
  • Canadian IPO, “Office Action dated Mar. 10, 2017”, dated Mar. 10, 2017, 1-3.
  • Eiji, N. , “High-Frequency Circuit and Its Manufacture”, Patent Abstracts of Japan, vol. 1998, No. 13, Nov. 30, 1998 & JP 10 209722 A (Seiko Epson Corp), Aug. 7, 1998.
  • EPO, , “Extended European Search Report”, EP 16188956.3, dated 2017, 1-9.
  • EPO, , “Extended European Search Report, EP16188956.3,”, dated Jan. 9, 2017, 1-9.
  • European Patent Office, , “EP Office Action dated Feb. 28, 2019”, for EP Application 11772625.7, Feb. 28, 2019, 11 pages.
  • European Patent Office, , “Office Action dated Nov. 28, 2018”, EP Application No. 15198585.0, Nov. 28, 2018, 4 pages.
  • Huang, Libo et al., “Theoretical and experimental investigation of adaptive antenna impedance matching for multiband mobile phone applications”, IEEE, Sep. 7, 2005, 13-17.
  • Hyun, S, , “Effects of strain on the dielectric properties of tunable dielectric SrTi03 thin films”, Applied Physics Letters, vol. 79, No. 2, Jul. 9, 2001.
  • India, Patent O. , “Examination Report”, for Application No. 9844/DELNP/2013, dated Apr. 25, 2018, 5 pages.
  • Intellectual Property India, “First Examination Report”, for Application No. 3160/CHE/2013 dated Jun. 5, 2018, Jun. 5, 2018, 5 pages.
  • Katsuya, K. , “Hybrid Integrated Circuit Device”, Patent Abstracts of Japan, Publication No. 03-276901, Date of publication of application: Sep. 12, 1991.
  • Nowrouzian, B. , “A necessary and sufficient condition for the BIBO stability of general-order bode-type variable-amplitude wave-digital equalizers,” ICME '03. Proc., USA, 2003, pp. 373-376. (Year: 2003).
  • Patent Cooperation Treaty, , “International Search Report and Written Opinion”, International Application No. PCT/US2010/046241, dated Mar. 2, 2011.
  • Patent Cooperation Treaty, , “International Search Report and Written Opinion”, International Application No. PCT/US2010/056413, dated Jul. 27, 2011.
  • Patent Cooperation Treaty, , “International Search Report and Written Opinion”, dated Nov. 16, 2011, International Application No. PCT/US/2011/038543.
  • Patent Cooperation Treaty, , “International Search Report and Written Opinion”, PCT Application No. PCT/US08/005085, dated Jul. 2, 2008.
  • Payandehjoo, Kasra et al., “Investigation of Parasitic Elements for Coupling Reduction in MultiAntenna Hand-Set Devices”, Published online Jan. 22, 2013 in Wiley Online Library (wileyonlinelibrary.com).
  • Pervez, N.K. , “High Tunability barium strontium titanate thin films for RF circuit applications”, Applied Physics Letters, vol. 85, No. 19, Nov. 8, 2004.
  • Petit, Laurent , “MEMS-Switched Parasitic-Antenna Array for Radiation Pattern Diversity”, IEEE Transactions on Antennas and Propagation, vol. 54, No. 9, Sep. 2006, 2624-2631.
  • Qiao, et al., “Antenna Impedance Mismatch Measurement and Correction for Adaptive COMA Transceivers”, IEEE, Jan. 2005.
  • Stemmer, Susanne , “Low-loss tunable capacitors fabricated directly on gold bottom electrodes”, Applied Physics Letters 88, 112905, Mar. 15, 2006.
  • Taylor, T.R. , “Impact of thermal strain on the dielectric constant of sputtered barium strontium titanate thin films”, Applied Physics Letters, vol. 80, No. 11, Mar. 18, 2002.
  • Xu, Hongtao , “Tunable Microwave Integrated Circuits using BST Thin Film Capacitors with Device”, Integrated Ferroelectrics, Department of Electrical Engineering and Computer Engineering, University of California, 2005, Apr. 2005.
  • Zuo, S. , “Eigenmode Decoupling for Mimo Loop-Antenna Based on 180 Coupler”, Progress in Electromagnetics Research Letters, vol. 26, Aug. 2011, 11-20.
  • Bezooijen, A. et al., “A GSM/EDGE/WCDMA Adaptive Series-LC Matching Network Using RF-MEMS Switches”, IEEE Journal of Solid-State Circuits, vol. 43, No. 10, Oct. 2008, 2259-2268.
  • Du Toit, , “Tunable Microwave Devices With Auto Adjusting Matching Circuit”, U.S. Appl. No. 13/302,617, filed Nov. 22, 2011.
  • Du Toit, , “Tunable Microwave Devices With Auto-Adjusting Matching Circuit”, U.S. Appl. No. 13/302,659, filed Nov. 22, 2011.
  • Greene, , “Method and Apparatus for Tuning a Communication Device”, U.S. Appl. No. 13/108,463, filed May 16, 2011.
  • Greene, , “Method and Apparatus for Tuning a Communication Device”, U.S. Appl. No. 13/108,589, filed May 16, 2011.
  • Hoirup, , “Method and Apparatus for Radio Antenna Frequency Tuning”, U.S. Appl. No. 13/030,177, filed Feb. 18, 2011.
  • Hyun, S. , “Effects of strain on the dielectric properties of tunable dielectric SrTi03 thin films”, Applied Physics Letters, 2004 American Institute of Physics.
  • Ida, I. et al., “An Adaptive Impedence Matching System and Its Application to Mobile Antennas”, TENCON 2004, IEEE Region 10 Conference, See Abstract ad p. 544, Nov. 21-24, 2004, 543-547.
  • Manssen, , “Method and Apparatus for Managing Interference in a Communication Device”, U.S. Appl. No. 61/326,206, filed Apr. 20, 2010.
  • Manssen, , “Method and Apparatus for Tuning Antennas in a Communication Device”, U.S. Appl. No. 12/941,972, filed Nov. 8, 2010.
  • Manssen, , “Method and Apparatus for Tuning Antennas in a Communication Device”, U.S. Appl. No. 13/005,122, filed Jan. 12, 2011.
  • McKinzie, , “Adaptive Impedance Matching Module (AIMM) Control Architectures”, U.S. Appl. No. 13/293,544, filed Nov. 10, 2011.
  • McKinzie, , “Adaptive Impedance Matching Module (AIMM) Control Architectures”, U.S. Appl. No. 13/293,550, filed Nov. 10, 2011.
  • McKinzie, , “Method and Apparatus for Adaptive Impedance Matching”, U.S. Appl. No. 13/217,748, filed Aug. 25, 2011.
  • Mendolia, “Method and Apparatus for Tuning a Communication Device”, U.S. Appl. No. 13/035,417, filed Feb. 25, 2011.
  • Paratek Microwave, Inc., , “Method and Appartus for Tuning Antennas in a Communication Device”, International Application No. PCT/US11/59620, filed Nov. 7, 2011.
  • Pervez, N.K. , “High Tunability barium strontium titanate thin films for RF circuit applications”, Applied Physics Letters, 2004 American Institute of Physics.
  • Petit, Laurent , “MEMS-Switched Parasitic-Antenna Array for Radiation Pattern Diversity”, IEEE Transactions on Antennas and Propagation, vol. 54, No. 9, Sep. 2009, 2624-2631.
  • Qiao, et al., “Antenna Impedance Mismatch Measurement and Correction for Adaptive COMA Transceivers”, IEEE, 2005.
  • Qiao, et al., “Measurement of Antenna Load Impedance for Power Amplifiers”, The Department of Electrical and Computer Engineering, University of California, San Diego, Sep. 13, 2004.
  • Spears, , “Methods for Tuning an Adaptive Impedance Matching Network With a Look-Up Table”, U.S. Appl. No. 13/297,951, filed Nov. 16, 2011.
  • Stemmer, Susanne , “Low-loss tunable capacitors fabricated directly on gold bottom electrodes”, University of California Postprints 2006.
  • Taylor, T.R. , “Impact of thermal strain on the dielectric constant of sputtered barium strontium titanate thin films”, Applied Physics Letters, 2002 American Institute of Physics.
  • Tombak, Ali , “Tunable Barium Strontium Titanate Thin Film Capacitors for RF and Microwave Applications”, IEEE Microwave and Wireles Components Letters, vol. 12, Jan. 2002.
  • Xu, Hongtao , “Tunable Microwave Integrated Circuits using BST Thin Film Capacitors with Device”, Integrated Ferroelectrics, Department of Electrical Engineering and Computer Engineering, University of California, 2005.
  • Zuo, S. , “Eigenmode Decoupling for Mimo Loop-Antenna Based on 180 Coupler”, Progress in Electromagnetics Research Letters, vol. 26, 2011, 11-20.
Patent History
Patent number: RE48435
Type: Grant
Filed: Apr 2, 2019
Date of Patent: Feb 9, 2021
Assignee: NXP USA, Inc. (Austin, TX)
Inventor: Matthew Russell Greene (Crystal Lake, IL)
Primary Examiner: Minh Dieu Nguyen
Application Number: 16/372,838
Classifications
Current U.S. Class: 455/550
International Classification: H04B 1/40 (20150101); H04W 24/02 (20090101); H03H 7/40 (20060101); H04B 1/04 (20060101);