Abstract: This disclosure relates to low noise amplifiers (LNAs) and more particularly to LNAs integrated on integrated circuit (IC) chips along with radio frequency (RF) amplifiers.

Abstract: A wireless device receives an input signal representing a signal of interest (e.g., one or more portions of a packet) on a wireless medium. The input signal may, in addition, contain narrowband interference signals. The wireless device removes the signal of interest from the input signal to produce a residue signal, and analyzes the residue signal to determine the presence of any interference bands in which narrowband interference signals may be present. The wireless device then removes the detected interference bands from the input signal. The residue signal may reveal the presence of interference signals, which might otherwise be hard to distinguish in the input signal. Thus, interference signals with power levels much lower than the power of the signal of interest may be detected and removed.

Abstract: A multibeam is configured to transmit a duplicate of a channel from one spot beam in another spot beam, which contains a remote monitoring station. The satellite is reconfigurable to select the channel which is duplicated, allowing the beams of the satellite to be monitored, without the need for a remote monitoring station in each beam.

Abstract: In a compensator for compensating mismatches, and in methods for such compensation, the compensator compensates for mismatches in output signals of a system with mismatches during normal operation of the system with mismatches. The compensator comprises: a mismatch estimator that monitors at least two mismatched signals output by the system with mismatches during normal operation and that generates matching parameters indicating an amount of mismatch between the at least two mismatched signals, the mismatch estimator updating the matching parameters during normal operation of the system with mismatches, and a mismatch equalizer that compensates mismatches in the mismatched signals output by the system with mismatches during normal operation of the system with mismatches in response to the matching parameters.

Abstract: A multipass noise detecting apparatus comprising: a smoothing process unit configured to receive input of a signal corresponding to electric field strength of a received signal and to smooth the signal; a delay process unit configured to delay the signal; an amplifying unit configured to amplify a signal output from the smoothing process unit; a pulse noise determining unit configured to compare a signal output from the delay process unit with a signal output from the amplifying unit to output a pulse noise determining signal indicating a period of presence of pulse noise; and a noise cancel process unit configured to carry out a process for removing pulse noise on the basis of the pulse noise determining signal, the process being applied to the signal output from the delay process unit.

Abstract: A method of configuring a tuner includes sampling a radio frequency and measuring at least one signal quality metric for the sampled frequency. It is determined whether there is co-channel interference on the sampled frequency based on the measurement of the at least one signal quality metric. The sampled frequency is selected as an operational frequency for the tuner if it was determined in the determining step that there is an absence of co-channel interference on the sampled frequency.

Abstract: An apparatus and method for short multipath mitigation. In one aspect the method comprises subtracting a first stronger path from a correlation function to obtain a first residual signal, wherein one component of the first residual signal is a weaker path; applying reconstruction on the first residual signal to obtain a first reconstructed weaker path; subtracting the first reconstructed weaker path from the correlation function to obtain a second residual signal; and applying reconstruction on the second residual signal to obtain a second stronger path. In one aspect, the apparatus includes an antenna for receiving a composite receive RF signal, a receiver front-end for converting the composite receive RF signal into a composite receive digital signal; and a processor for performing signal correlation on the composite receive digital signal to obtain a correlation function and for processing the correlation function to obtain a desired signal.

Abstract: Providing interferer diversity is disclosed. A received wireless signal is processed to obtain a first processed signal in which a desired information is translated to a first frequency in a first Nyquist zone. The received wireless signal processed to obtain a second processed signal in which the desired information is translated to a second frequency in the first Nyquist zone. The second frequency is different than the first frequency.

Abstract: A digital wireless communication system for increasing the number of users capable of communicating over a network permits multiusers to transmit information simultaneously on the same channel of frequency. The primary example of such a system would be that employing radio frequency transmissions, even optical transmissions; however, the invention will also apply to magnectic detections such as in the reading of information stored on a magnetic tape. It is possible to increase overall throughput in terms of total number of bits transmitted through the shared medium by all users of a multiple access system if the signals are allowed to interfere. The present invention provides a multiuser detection process and apparatus that is capable of pulling apart signals in heavy interference in real time by combining the signals received from two or more spatially seperated collectors or antennas.

Abstract: The semiconductor integrated circuit (RF IC) for a mobile telephone capable of transmitting/receiving the signals of plural bands reduces the DC offsets of the amplifiers located in the following stages of the mixers that demodulate or down-convert the reception signals. The invention scrambles the signal lines to transmit the outputs of the plural mixers that demodulate or down-convert the reception signals of different bands, so as to avoid the adjacent signal lines from making the same combination from the starting ends to the finishing ends.

Abstract: A communication system employing site diversity combing to increase link availability includes at least two receivers at receive sites within a single downlink beam separated by enough distance to provide decorrelation of weather phenomena—such as rain fade outages. A signal transmits digital symbols to all the receivers and may use bandwidth efficient modulation with forward error correction coding. Sampled symbol values for each codeword are produced at each receiver, which are connected by one or more ground links so that all data can be collected at one site. At least two different soft-decision computation modules translate the sampled symbol values from the different receivers into different sets of soft-decision values—which may be log-likelihood-ratio (LLR) values reflecting the probability value for each bit of the codeword—that are digitally synchronized and combined for use by a decoder. The technique thus avoids disadvantages of either coherent waveform combining or BER-based digital switching.

Abstract: A mobile station is disclosed that includes a first antenna, at least one second antenna, and a receiver coupled to the first antenna. The receiver includes first control logic configured to generate a notification of the receiver being able to receive a reception frequency band and includes a transmitter coupled to the at least one second antenna and the receiver. The transmitter communicates radio frequency (RF) signals in a transmission frequency band over an RF transmit path to the at least one second antenna. The transmitter includes a tunable filter coupleable to the RF transmit path, and second control logic configured to adjust at least one characteristic of the tunable filter based at least in part on the notification. The adjustment is performed to reduce, when the tunable filter is coupled to the RF transmit path, interference caused by transmission in the transmission frequency band with reception in the reception frequency band.

Abstract: A signal separation device is disclosed that is able to reduce a number of calculations required when separating a received signal transmitted from transmission devices into the individual transmission signal. The signal separation device includes a signal point derivation unit that multiplies the received signal with respective elements of a unitary matrix, and derives at least one received-signal signal point on a signal constellation diagram; a definition unit that defines plural sections on the signal constellation diagram, each of the sections including a predetermined number of signal points; a detection unit that detects a received-signal section from the sections, the received-signal section including the received-signal signal point; a selection unit that selects signal points in the received-signal section as candidates of the received-signal signal point; and a determination unit that determines the transmission signals based on the selected signal points.

Abstract: An integrated circuit includes clock deskew circuitry. The deskew circuitry includes a loop circuit to align an input clock signal with an output clock signal, and also aligns transmitted data with the output clock signal.

Abstract: A signal detector arranged in a receiver of a wireless communication device includes a variable passband bandpass filter configured to bandlimit a received signal using a variable passband; a signal parameter detection unit configured to detect a signal parameter of each of a plurality of signals contained in the received signal; a detection order determination unit configured to determine a detection order for detecting the signals from the received signal based on the signal parameter; a parameter control unit configured to control the passband of the variable passband bandpass filter based on the detection order and the signal parameter; and an equalization and decision unit configured to equalize and decide the bandlimited signal output from the variable passband bandpass filter. The signals contained in the received signal are successively detected from the received signal according to the detection order by means of the variable passband bandpass filter and the equalization and decision unit.

Abstract: A television tuner that receives a television signal using a smart antenna includes a rescan unit that executes rescan; that is: that when an instruction that instructs direct selection of a reception channel on which a television signal is currently received is issued during reception of a television broadcast service, causes an antenna control section to vary or control the receiving direction of the smart antenna and causes a signal state detector section to detect the states of signals sampled in all receiving directions; and that if the state of a signal detected by the signal state detector section agrees with a predetermined signal state, preserves the receiving direction of the smart antenna in which the signal is sampled. Consequently, rescan can be executed for all the receiving directions of the smart antenna by performing a simple manipulation.

Abstract: A method in which one of a high-side mix mode and a low-side mix mode is selected in response to an interference characteristic of a desired channel of a radio frequency (RF) input signal is disclosed. In the high-side mix mode, a direct digital frequency synthesizer (130) is initialized to output a digital local oscillator signal at a first frequency suitable for performing a high-side mix of the desired channel to an intermediate frequency (IF). In the low-side mix mode, the direct digital frequency synthesizer (130) is initialized to output the digital local oscillator signal at a second frequency suitable for performing a low-side mix of the desired channel to said IF. The RF input signal is mixed with the digital local oscillator signal to provide an IF output signal at the IF.

Abstract: An AM radio receiving circuit is disclosed that comprises a front end circuit that converts an input AM modulation signal to an intermediate frequency signal that in turn is output; a pulse noise detecting circuit that detects pulse noise included in the AM modulation signal; a pulse noise removing circuit that removes the pulse noise included in the intermediate frequency signal output from the front end circuit based on the detection result of the pulse noise detecting circuit to output the signal; and a detecting circuit that detects the intermediate frequency signal output from the pulse noise removing circuit after removing the pulse noise to output an audio signal.

Abstract: A communication system employing site diversity combing to increase link availability includes at least two receivers at receive sites within a single downlink beam separated by enough distance to provide decorrelation of weather phenomena—such as rain fade outages. A signal transmits digital symbols to all the receivers and may use bandwidth efficient modulation with forward error correction coding. Sampled symbol values for each codeword are produced at each receiver, which are connected by one or more ground links so that all data can be collected at one site. At least two different soft-decision computation modules translate the sampled symbol values from the different receivers into different sets of soft-decision values—which may be log-likelihood-ratio (LLR) values reflecting the probability value for each bit of the codeword—that are digitally synchronized and combined for use by a decoder. The technique thus avoids disadvantages of either coherent waveform combining or BER-based digital switching.

Abstract: A radio receiver may comprise a receiver adaptable for receiving a plurality of broadcast streams over a plurality of broadcast channels, wherein the receiver will attempt to receive a selected broadcast stream on a selected broadcast channel, and if the selected broadcast stream is not receivable on the selected broadcast channel, the receiver will attempt to receive the selected broadcast stream on an alternative broadcast channel. A computer readable medium may allow a user of a receiver to create a composite stream comprising at least one portion selected from each of at least two of a plurality of broadcast streams. A method of open interface merge replication may involve comparing data between first and second databases, and if a conflict exists, updating one of the first and second databases with at least a portion of data from the other of the first and second databases to resolve the conflict.

Abstract: A mobile device comprises a receiver unit that has at least two receivers to implement multi-antenna receive diversity. A control unit estimates, at the mobile, an amount of utilization by a traffic channel of the mobile of total transmission power capacity at a base station. The mobile applies multi-antenna receive diversity in the mobile device based on the power capacity utilization. The mobile estimates an amount of power a network is transmitting to the mobile relative to a pilot reference. Other indicators are based on quality of the traffic channel between the mobile and the network, capacity limiting resources, a number of sectors in a soft hand-off in a wireless system, etc. The indicators are used to control application of multi-antenna receive diversity in a mobile device.

Abstract: A combined SAIC receiver and a multiple-antenna, receive diversity receiver are employed to reduce interference in a wireless system. The real and imaginary parts of the de-rotated signal for each receive path associated with an antenna are separately filtered and a combined output signal of all receive paths is generated. The weighting coefficients are adjusted based on an error signal produced by comparing the combined output signal with a reference signal. The weighting coefficients are initially set based on an MMSE/LS type of signal processing criteria, where the reference signal is the Training Sequence Code (TSC). Subsequent adjustment/tracking can be accomplished by using known tracking algorithms, e.g. LMS or RLS, or the coefficients can be re-computed using MMSE/LS processing. The reference signal for tracking may be a combination of the TSC and estimated data symbols provided by an equalizer.

Abstract: An adaptive receiver is disclosed for optimally receiving and processing signals. The receiver utilizes one or more memory blocks to store groups of incoming symbols. The groups of symbols are processed by a channel estimation subsystem to determine channel characteristics. The receiver determines the appropriate demodulation and decoding strategy to implement based on the determined channel characteristics. The receiver includes a plurality of demodulation and decoding schemes, one of which is selected based on the results of a channel estimation analysis.

Abstract: A method and apparatus for transmitting data from a first node to a second node of a communication system are provided. The method includes, in a first mode of operation, transmitting data via a first communication channel in which the power level of the channel at the first node is not indicated to the second node, and in a second mode of operation transmitting the data via said first communication channel and indicating the power level of the channel at the first node to the second node.

Abstract: A signal conditioning circuit contains an oscillator which is connected to the inputs of two mixers. The output of one mixer is coupled, so as to form a feedback path, to a frequency divider circuit whose first output is coupled to the second input of the first mixer. A second signal output of the frequency divider circuit carries a signal with a phase shift of 90 degrees with respect to the signal at the first signal output of the frequency divider circuit. The second signal is supplied to a second input of the second mixer. Feedback results in undesirable signal components in the in-phase and quadrature components being suppressed. At the same time, the in-phase and quadrature components have a fixed phase relationship with respect to one another. The signal conditioning circuit allows desired non-integer division ratios to be achieved.

Abstract: A waveform reconstruction circuit receives an rf signal from an antenna, digitizes it, and then generates an undistorted reconstructed waveform. The reconstructed waveform can then be conventionally mixed and demodulated to extract useful signal information with enhanced receiver fidelity and sensitivity.

Abstract: Multiple cochannel FM signals received, for example, in an overloaded signal environment may be separated using parallel interference cancellation techniques.

Abstract: In the diversity receiver, the RF switcher switches the received signals to supply them to the RSSI power detector equipped with diversity function. Subsequently, the RSSI power detector with diversity function feeds the RF switcher with an antenna switching signal. According to the determination of antennas at this instance, an IQ start-up signal for starting up the I/Q subsection is produced to make the I/Q subsection operate assuredly in response to a signal intended to receive, without operating the I/Q subsection in response to an erroneous detection of noise during processing therein, thereby eliminating useless operation.

Abstract: Techniques for multiple access differential M-ary coding applications that can be optionally aided by multiuser detection (MUD) are disclosed. An initial hopped feature decoding is performed to provide data estimates for each user represented in a received co-channel signal. Interference cancellation can then be performed using MUD, thereby providing an interference-cancelled signal. Data estimates remaining are then re-decoded. Iteration on the interference cancellation and re-decoding can be carried out to satisfy a particular rule of iteration, although iteration is not always necessary. The final decoded signal can then be provided to its destination.

Abstract: A wireless network infrastructure supporting a plurality of wireless end point devices containing a wireless access point and a plurality of end point wireless devices that supports single transmission and reception and/or concurrent interfering transmission and reception. The wireless access point transmits data to the end point wireless devices that supports single transmission and reception during a first portion of a first data transmission period and simultaneously transmits data to the end point wireless devices that supports concurrent interfering transmission and reception during a second portion of the first data transmission period. The wireless access point simultaneously receives data from the end point wireless devices that supports concurrent interfering transmission and reception during a second data transmission period.

Abstract: Interference suppression in a receiver in a wireless network that utilizes training sequences for synchronization and channel estimation, wherein the training sequence of an interfering channel overlaps the training sequence of a desired channel to cause degraded channel estimation, by generating a channel estimate for a carrier part of a received signal; generating a residual signal where the carrier part has been removed from the received signal; generating covariance matrix estimates for interferer channel estimate candidates; selecting carrier and interferer channel estimates having the lowest energy in the covariance matrix; and, explicitly generating the selected interferer channel estimate.

Abstract: An adjacent interference removal device capable of providing an improved reception quality. An IF signal Sin having passed through an IF filter having a pass frequency band width of 200 kHz is supplied to a first narrow band filter having a pass frequency band width extending from a center frequency (carrier frequency) of the IF filter to +50 kHz, as well as to a second narrow band filter having a pass frequency band width extending from a center frequency (carrier frequency) of the IF filter to ?50 kHz.

Abstract: An Inter-modulation distortion measurement and correction method which could be applied over a communication channel that is a combination of either or both analog and digital channels. This method is applicable for a communication system between a modem pair.

Abstract: Phase and amplitude offsets of a multicarrier transceiver may be reduced by measuring receiver amplitude and phase mismatches of receiver radio-frequency (RF) circuitry by performing a fast Fourier transform (FFT) on a receiver calibration signal.

Abstract: An LNB for simultaneous reception of circular and linear polarization radio frequency signals, having a circular waveguide coupled to a waveguide to microstrip turnstile transition. The microstrip outputs coupled to a multi-layer printed circuit board having symmetrical signal paths on separate layers. Each symmetrical signal path including a first combiner coupled to a low noise amplifier that is coupled to a splitter. A first output of each of the splitters having a linear polarization and a second output of each of the splitters coupled to a branch line combiner having two outputs, each of the two outputs having opposite hands of circular polarization.

Abstract: An architecture for a receiver front end utilizes a dual output low noise amplifier (102) driving separate, fixed preselectors (104, 106) coupled to a transformer (108) to generate a single ended output (113). A pair of blocks coupled in series provides a dual band output. Additional pairs of blocks (201, 203) can be cascaded in parallel to provide additional frequency bands of operation. The front end architecture of the present invention provides switchless multi-band operation to a communication device.

Abstract: A multipass noise detecting apparatus comprising: a smoothing process unit configured to receive input of a signal corresponding to electric field strength of a received signal and to smooth the signal; a delay process unit configured to delay the signal; an amplifying unit configured to amplify a signal output from the smoothing process unit; a pulse noise determining unit configured to compare a signal output from the delay process unit with a signal output from the amplifying unit to output a pulse noise determining signal indicating a period of presence of pulse noise; and a noise cancel process unit configured to carry out a process for removing pulse noise on the basis of the pulse noise determining signal, the process being applied to the signal output from the delay process unit.

Abstract: A semiconductor integrated circuit device includes a semiconductor substrate; at least one integrated circuit block formed in the semiconductor substrate; a first electrode pad which receives a first clock, the first electrode pad being disposed on the semiconductor substrate; a wiring line which electrically connects the integrated circuit block and the first electrode pad, the wiring line being disposed on the semiconductor substrate; and a second electrode pad which receives a second clock having the same frequency as and opposite polarity from the first clock, the second electrode pad being disposed in a position adjacent to the first electrode pad on the semiconductor substrate and isolated from the integrated circuit block.

Abstract: A Multi-Input/Multi-Output (MIMO) receiver may include a plurality of receiving antennas that receive a plurality of radio signals and an estimation section that finds channel estimation values of the plurality of radio signals. A MIMO separation section separates, using a MIMO scheme, the plurality of radio signals in accordance with the channel estimation values, and a compensation section compensates for channel variations of the plurality of radio signals. A selection section selects one of the MIMO separation section and the compensation section.

Abstract: A multiple frequency RF communications receiver is disclosed which permits greater integration on standard silicon chips and consumes less power than previous receivers. A new method for selecting the various frequency bands with a high amount of isolation and low power consumption is described. Compared to previous receiver implementations, there is no loss of selectivity in the receiver.

Abstract: From a delay profile, path selectors 105a˜105n discard the signals other than those corresponding to valid paths, such as noise, output the channel values, which are obtained through the selection of valid paths alone, to JD decoder 106, and output the received levels of the valid paths to multipliers 108a˜108n. JD decoder 106 performs joint detection operation and multiplies the operation result by a received signal that is output from delayer 103. Allocator 107 separates the soft decision data of individual users on a per user basis. Multipliers 108a˜108n multiply outputs of JD decoder and received levels output of path selectors 105a˜105n. Error correction decoder 109a˜109n performs the hard decision of the soft decision data so as to obtain each user's demodulation data.

Abstract: A method and a circuit for detecting a modulation factor in a signal received in amplitude modulation, including comparing the received signal with two first values, comparing the received signal with two second values ranging between the first two values, and considering the presence of an insufficient modulation depth if the received signal ranges between at least two of said values.

Abstract: A first image (200) of a transmitted signal is detected within a received signal containing a plurality of images of the transmitted signal. This is accomplished by detecting a second image (210) of the transmitted signal. A set of characteristics of the second image of the transmitted signal is determined, and subsequently used to detect the first image (200) of the transmitted signal.

Abstract: In an adaptive array (2000), fading rate of a user is measured by a fading rate measuring circuit (2300), and the transmit weight vector is weighted in accordance with the fading rate by a transmitting circuit (2400). Thus, transmission power is increased for a user of which fading rate is large, and thus transmission directivity control for such a user becomes possible.

Abstract: A cosite interference rejection system allows cancellation of large interfering signals with an optical cancellation subsystem. The rejection system includes an interference subsystem coupled to a transmit system, where the interference subsystem weights a sampled transmit signal based on a feedback signal such that the weighted signal is out of phase with the sampled transmit signal. The optical cancellation subsystem is coupled to the interference subsystem and a receive antenna. The optical cancellation subsystem converts an optical signal into a desired receive signal based on an interfering coupled signal and the weighted signal. The weighted signal is therefore used to drive the optical cancellation subsystem. The rejection system further includes a feedback loop for providing the feedback signal to the interference subsystem based on the desired receive signal.

Abstract: A high frequency device includes a transmission/reception amplifier 13 that amplifies and outputs an input signal, and a transmission/reception switch 2 that gang switches internally so that during transmission an input of the transmission/reception amplifier 13 is connected to an up mixer and an output of the transmission/reception amplifier 13 is connected to an antenna unit 5, and so that during reception the output of the transmission/reception amplifier 13 is connected to a down mixer and the input of the transmission/reception amplifier 13 is connected to the antenna unit 5.

Abstract: A method is provided for reducing a DC bias in a receiver. This method includes isolating a second circuit portion from a first circuit portion (535) and determining a second DC bias correction value for the second circuit portion that will eliminate a second DC bias at the isolated second circuit portion (540). The second circuit portion is then connected to the first circuit portion (550) and a bias-maximizing code word is generated at the first circuitry (505). A first DC bias correction value is then determined that will eliminate a first DC bias at the first circuit portion (555). The bias-maximizing code word is formed such that: a first integrated value of a first half of the bias-maximizing code word has a positive value, and a second integrated value of a second half of the bias-maximizing code word over half of the code word length has a negative value.

Abstract: An adaptive receiver is disclosed for optimally receiving and processing signals. The receiver utilizes one or more memory blocks to store groups of incoming symbols. The groups of symbols are processed by a channel estimation subsystem to determine channel characteristics. The receiver determines the appropriate demodulation and decoding strategy to implement based on the determined channel characteristics. The receiver includes a plurality of demodulation and decoding schemes, one of which is selected based on the results of a channel estimation analysis.

Abstract: An adaptive intelligent radio module (IRM) is provided in an intelligent radio design for gateways between satellite and terrestrial networks. The intelligent radio module monitors channel signal quality at the channel units of the gateway to determine whether the quality of a channel unit is below a predetermined quality threshold. If the channel quality is greater than or equal to the predetermined quality threshold, then a standard channel unit is employed, and nominal algorithms are used to process the channel. However, if the channel quality is below the quality threshold, then a high performance channel unit is used that employs complex algorithms unique to the particular quality defect of the channel quality. Various additional functions can be performed at the receive side and the transmit side of the channel units monitored by the IRM. Further, the IRM can add or enhance existing algorithms in accordance with new technology.

Abstract: An electronic apparatus according to the present invention includes two modules which decode high frequency analog signals. Furthermore, each of the modules is provided with an RF section at a position away from the center of the module in either longitudinal direction to carry out radio communications using high frequencies. In this electronic apparatus, the two modules are arranged so that their longitudinal sides extend parallel with each other in opposite directions. The two modules are also misaligned with each other in the longitudinal direction so that the RF sections lie away from each other and so that connectors to which signals subject to noise interference are inputted lie away from each other.