Abstract: A hybrid position determination system is disclosed. A mobile device may determine a number of pseudo ranges based on a first position determination system, such as a Global Positioning System. In instances where the position of the mobile device is underdetermined because of an insufficient number of satellite pseudo ranges, the mobile device shares position information with other devices. The other devices may include other mobile devices. A first mobile device may determine its position based on an underdetermined number of satellite pseudo ranges by determining pseudo ranges to other mobile devices. In other embodiments, the number of satellite pseudo ranges may be insufficient to generate an absolute position determination of a single mobile device. In this underdetermined condition, mobile devices may determine a common location of the group or may determine a relative positioning of members of the group.

Abstract: In a communication system, a method for estimating a transmitted signal is disclosed. A communication signal is received. A delay-power analyzer analyzes the communication signal. A delay spread is then estimated from information obtained from the delay-power analyzer. A new equalizer filter length is determined based on the estimated delay spread. An equalizer is configured to use the new equalizer filter length.

Abstract: Method and apparatus for subsampling phase spectrum information by analyzing and reconstructing a prototype of a frame. The prototype is analyzed by correlating phase parameters generated from the prototype with phase parameters generated from a reference prototype in multiple frequency bands. The prototype is reconstructed using linear phase shift values by producing a set of phase parameters of the reference prototype, generating a set of linear phase shift values associated with the prototype, and composing a phase vector from the set of phase parameters and the set of linear phase shift values across multiple frequency bands. The prototype is reconstructed using circular rotation values by producing a set of circular rotation values associated with the prototype, generating a set of bandpass waveforms associated with the phase parameters of the reference prototype in multiple frequency bands, and modifying the set of bandpass waveforms based upon the circular rotation values.

Abstract: Methods and apparatus for providing location information to an Access Terminal (AT) when the Access Network (AN) is unable to contact a last serving PDSN, else maintaining the previous location information. In one embodiment, AN elements within an area supported by a Packet Data Serving Node (PDSN) are given a same Access Network ID (ANID). In this way, movement of the AT within the area supported by the PDSN do not initiate an update of location information. The AT receives location information specific to the PDSN and not the AN.

Abstract: In a method for achieving higher S/N, one or more signals are received and processed to provide one or more streams of samples. In a first processing scheme, the sample stream(s) are equalized and combined within an equalizer to generate symbol estimates, which may be subsequently processed (e.g., despread and decovered) to provide a first stream of recovered symbols. The sample stream(s) may be equalized prior to being combined. In this case, each sample stream is filtered with a set of coefficients and may be scaled with a scaling factor. The scaled samples for all streams are then combined to generate the symbol estimates. Alternatively, the sample stream(s) may be combined prior to being equalized. In this case, each sample stream is scaled by a scaling factor. The scaled samples for all streams are then combined to generate summed samples that are further filtered with a set of coefficients to generate the symbol estimates.

Abstract: A method for sending a secure message within a communications network which operates a short message service (SMS) according to an SMS protocol. The method consists of transmitting an SMS message of a predefined type from a mobile transceiver over the network, receiving the SMS message at an SMS receiver, and transmitting an authorization request, responsive to the SMS message and the predefined type, from the SMS receiver to the mobile transceiver. The method further includes receiving the authorization request at the mobile transceiver, transmitting a pre-determined confirmation code from the mobile transceiver responsive to the authorization request, and forwarding the SMS message from the SMS receiver to a message destination responsive to receipt of the confirmation code at the SMS receiver.

Abstract: In a data communication system capable of variable rate transmission, high rate packet data transmission improves utilization of the forward link and decreases the transmission delay. Data transmission on the forward link is time multiplexed and the base station transmits at the highest data rate supported by the forward link at each time slot to one mobile station. The data rate is determined by the largest C/I measurement of the forward link signals as measured at the mobile station. Upon determination of a data packet received in error, the mobile station transmits a NACK message back to the base station. The NACK message results in retransmission of the data packet received in error. The data packets can be transmitted out of sequence by the use of sequence number to identify each data unit within the data packets.

Abstract: A system and method are disclosed for providing a FSK demodulator using DLL and a demodulating method which detects a time order of the rising edges of square waves that correspond to two modulation frequencies and an in-between frequency and demodulates the relevant frequencies into data. The FSK demodulator includes a band-pass filter, an amplitude limiter for converting a waveform of the frequency filtered into a square wave, a delay line for receiving the square wave from the amplitude limiter and delaying the square wave for a delay time, a delayed flip-flop (DFF) for receiving an output signal from the amplitude limiter and an output signal from the delay line, determining which rising edge of the two input signals is earlier at a given time, and outputting the result of the determination as data, and a DLL circuit that locks the delay time of the delay line.

Abstract: A main die and a stacked die are included in the same component package. A transmission gate (370) is implemented on the main die, and can be enabled to receive leakage current in a connection (318) between the main die and the stacked die, and to conduct the leakage current to a bonding pad (344) that is accessible external to the package. Thus, the connectivity between the main die and the stacked die can be tested after the dies are packaged. The transmission gate is disabled during high-speed testing and normal operation. The package can also include a multiplexer (364) that is enabled during high-speed testing to input and output test signals at the package level. A direction signal is used to indicate whether test signals are being input to or output from the main die.

Abstract: An active filter with compensation to reduce Q-enhancement is disclosed. The filter may include a first amplifier and a second amplifier coupled to the first amplifier. The second amplifier having a negative feedback loop including a buffer having a plurality of compensation resistors. The compensation resistors may each have a value that results in the biquad filter having substantially zero Q-enhancement. The biquads may cascaded to form higher order filters.

Abstract: A system and method is taught for controlling a power level of transmissions in a communication system. A first station of the communication system transmits signals on a communication channel and a pilot channel. A second station of the communication system measures a signal to noise ratio of the received signal, determines an expected signal to noise ratio of the received signal, determines an indicator in accordance with said measured signal to noise ratio and the expected signal to noise ratio, and transmits the indicator. The indicator is received at the first station the indicator and determines the power level of the next transmission according to said received indicator. Additionally, methods and systems for the measurement of the signal to noise ratio of the received signal, the determination of the expected signal to noise ratio of the received signal, and the determination of the indicator are disclosed.

Abstract: Techniques for generating quality indicator bits in a wireless communication system (e.g., a cdma2000 that implements IS-2000). In one method, a determination is first made whether a good data frame was received from a first transmission for the current frame interval. This first transmission may be a non-continuous transmission on a forward dedicated control channel (F-DCCH) defined by IS-2000. If a good data frame was received, then a quality indicator bit is generated based on the good data frame. Otherwise, the quality indicator bit is generated based on a second transmission, which may comprise power control bits that are transmitted even when no data frames are sent in the first transmission. The received signal quality for the power control bits can be measured and compared against a threshold, and the quality indicator bit is then set based on the result of the comparison. The threshold may be dynamically updated.

Abstract: According to a disclosed embodiment, a processor is configured to detect when a wireless mobile unit is in an High Data Rate (HDR) area. The processor is further configured to determine a need for exchanging data between the wireless mobile unit and a base station. The processor invokes a data burst optimizer to exchange data between the wireless mobile unit and the base station when the wireless mobile unit is in the HDR area. The data burst optimizer is configured to exchange data between the wireless mobile unit and the base station in an HDR area. The data burst optimizer is further configured to continuously detect when the wireless mobile unit is in the HDR area. The data burst optimizer is configured to stop exchanging data between the wireless mobile unit and the base station when the wireless mobile unit is not in the HDR area.

Abstract: Techniques for converting short messages between different formats (e.g., from GSM SMS to CDMA SMS) such that pertinent control information is retained without changing the fundamental structure of these message formats. A new value is defined for the Msg_Encoding field in the User Data subparameter of the CDMA SMS message to indicate that the content of this message is an encapsulated GSM SMS message. The Message_Type field in the User Data subparameter may be used to carry data coding scheme information for the encapsulated GSM SMS message. At a recipient mobile station, the value in the Msg_Encoding field is checked to determine whether or not the CDMA SMS message includes an encapsulated GSM SMS message. If the answer is yes, then the user data in the CHARi fields of the CDMA SMS message is processed based on the data coding scheme information from the Message_Type field.

Abstract: A method and apparatus for determining the data rate of a reverse link communication of an access terminal includes receiving a reverse activity bit (RAB) from an access point in the communication system, and passing the RAB to a digital filter to produce a filtered RAB. In one embodiment, the reverse link data rate is determined based on the filtered value of the RAB. Furthermore, a processor in the access terminal may determine whether the access terminal is in an idle mode, and passing a non-busy state value of the RAB to the digital filter when the access terminal is in the idle mode. The filtered RAB may be compared to a threshold to determine a mode of reverse link data rate determination. The mode defines a set of criteria for an aggressiveness level of increasing or decreasing the reverse link communication data rate. The processor, therefore, determines the data rate based on the filtered reverse activity bit in accordance with the determined mode.

Abstract: A method of identifying whether a first signal received at a subscriber station has been relayed by a repeater. The method involves measuring at the subscriber station a time difference of arrival between the first signal and a second signal. A hyperboloid or other potential solution surface is then formed from the measured time difference of arrival. A determination is then made whether or not the first signal was relayed by a repeater based on information derived from the potential solution surface.

Abstract: For determining use of receive diversity in a mobile station, a control system (210 or 401) determines a demand level for use of communication resources. A transmitter (300) communicates a message indicating use of receive diversity at a mobile station based on the determined demand level. In another aspect, a receiver (200) receives a channel and determines transmit power level of the channel for being at a lower or upper transmit power level limit. The control system (210 or 401) controls receive diversity by selecting a number of receiver chains (290) based on the determined transmit power level. In another aspect, receiver (200) receives a channel and determines a channel condition of the channel and duration of the channel condition. Control system (210 or 401) controls receive diversity by selecting a number of receiver chains (290) based on the determined channel condition and the duration.

Abstract: A method and apparatus for conserving home agent resources in mobile Internet Protocol (IP) deployment is disclosed. In a wireless communication system supporting mobile IP, a registration request message is sent by a mobile node to a home agent. The registration request includes a care-of address. A home address is provided for the mobile node and is associated with the care-of address. The home agent provides an inactivity timer for the mobile node to monitor the communication activity of the mobile node. In addition, the home agent monitors a condition of a resource. When the condition satisfies an overload condition, the home agent starts a reclaiming resources process that utilizes the inactivity timer for the mobile node.

Abstract: A method and apparatus for determining the data rate of a reverse link communication of an access terminal includes receiving a reverse activity bit (RAB) from an access network in the communication system, and passing the RAB to multiple digital filters to produce filtered RABs. The reverse link data rate is determined based on these filtered values of the RABs. From the filtered RAB values a continuous fluid power level is determined each rate update. The access terminal maps the continuous fluid power level to actual physical transmissions by dithering among discrete power levels allowed by the physical layer.

Abstract: A method and apparatus for providing soft handoff in a mobile communication system. In current systems is that the members of active set are determined in accordance with comparisons of measured pilot energy with fixed thresholds. However, the value of providing a redundant communication link to a mobile station depends strongly on the energy of other signals being provided to the mobile station. In the present invention, the signal strengths of other base stations in communication with a mobile station are considered when determining whether adding a base to that set of base stations in communication with the remote station is of sufficient value to justify the impact on system capacity.