Abstract: Systems and methods of synchronizing a fountain code transmitting end and receiving end. In one embodiment, the fountain code transmitting end includes a first pseudorandom number generator, a second pseudorandom number generator, and a first transceiver. The method includes generating, at the first pseudorandom number generator, a first random number based on a seed. The method further includes generating, at the second pseudorandom number generator, a first plurality of unique random numbers based on the first random number. The method also includes selecting, at the fountain code transmitting end, a first subset of data blocks of a plurality of data blocks based on the first plurality of unique random numbers. The method further includes generating, at the fountain code transmitting end, a first communication block based on the first subset of data blocks. The method also includes transmitting, via the first transceiver, the first communication block and the seed.

Abstract: Systems and methods of synchronizing a fountain code transmitting end and receiving end. In one embodiment, the fountain code transmitting end includes a first pseudorandom number generator, a second pseudorandom number generator, and a first transceiver. The method includes generating, at the first pseudorandom number generator, a first random number based on a seed. The method further includes generating, at the second pseudorandom number generator, a first plurality of unique random numbers based on the first random number. The method also includes selecting, at the fountain code transmitting end, a first subset of data blocks of a plurality of data blocks based on the first plurality of unique random numbers. The method further includes generating, at the fountain code transmitting end, a first communication block based on the first subset of data blocks. The method also includes transmitting, via the first transceiver, the first communication block and the seed.

Abstract: Disclosed herein are methods and systems for canceling a blocking signal to obtain a desired signal. An example process includes receiving both a blocking signal and a set of blocking bits corresponding to a demodulation of the blocking signal. A remodulated blocking signal is generated by modulating the received set of blocking bits. The remodulated blocking signal is passed through a blocking-band bandpass filter to generate an estimated blocking signal, and is also passed through a desired-band bandpass filter to generate an unconditioned reference signal. One or more signal-parameter differences between the blocking signal and the estimated blocking signal are identified, and one or more signal compensations are accordingly applied to the unconditioned reference signal to generate a conditioned reference signal, which is then output to a blocking-signal-canceling system.

Abstract: A method and apparatus for a method and apparatus for correlation canceller for interference mitigation with adaptive DC offset cancellation for a dual mode communication device includes detecting an active signal transmitting in one mode; configuring integrators associated with the adaptive correlation canceller into gain amplifiers; detecting DC offset utilizing the gain amplifiers and comparators; and configuring the integrators from the gain amplifiers back to integrators with the DC offset applied thereto. The active signal transmitting in one mode can be Long Term Evolution (LTE) which is adjacent to a signal in another mode.

Abstract: Disclosed herein are methods and systems for canceling a blocking signal to obtain a desired signal. An example process includes receiving both a blocking signal and a set of blocking bits corresponding to a demodulation of the blocking signal. A remodulated blocking signal is generated by modulating the received set of blocking bits. The remodulated blocking signal is passed through a blocking-band bandpass filter to generate an estimated blocking signal, and is also passed through a desired-band bandpass filter to generate an unconditioned reference signal. One or more signal-parameter differences between the blocking signal and the estimated blocking signal are identified, and one or more signal compensations are accordingly applied to the unconditioned reference signal to generate a conditioned reference signal, which is then output to a blocking-signal-canceling system.

Abstract: A method and apparatus for a method and apparatus for correlation canceller for interference mitigation with adaptive DC offset cancellation for a dual mode communication device includes detecting an active signal transmitting in one mode; configuring integrators associated with the adaptive correlation canceller into gain amplifiers; detecting DC offset utilizing the gain amplifiers and comparators; and configuring the integrators from the gain amplifiers back to integrators with the DC offset applied thereto. The active signal transmitting in one mode can be Long Term Evolution (LTE) which is adjacent to a signal in another mode.

Abstract: A method and apparatus is provided for mitigating multiband self-interference using multipath cancellation. A dual-band transceiver receives an incoming radio-frequency signal that includes a multipath self-interference component generated by the transmission of an outgoing radio-frequency signal. The transceiver creates a plurality of reference signals from the outgoing radio-frequency signal by introducing delay values with respect to the outgoing signal. The transceiver adjusts the amplitude and phase of each of the delayed reference signals and combines the resulting signals with the incoming radio-frequency signal to cancel the self-interference component. The delay values may be determined adaptively. The systems and methods described herein are particularly useful for dual-band transceivers capable of communicating simultaneously using Long-Term Evolution (LTE) wideband signals and Public-Safety Narrowband (PSNB) signals.

Abstract: A method and apparatus for synchronizing a communication device in a communication system includes receiving a transmission from another communication device. The transmission comprises a plurality of time slots and a plurality of signaling fields inserted between the time slots. The plurality of signaling fields include a set of signaling fields of a first information type and a set of signaling fields of a second information type. The method includes detecting at least two consecutive signaling fields of the first information type, recovering a received pattern contained in a nth signaling field of the second information type, predicting patterns corresponding to (n+1)th to (k?1)th signaling fields of the second information type, comparing previously predicted patterns corresponding to the (n)th signaling field with the recovered pattern in the received (n)th signaling field and achieving synchronization when at least ‘m’ matches are obtained between the predicted and the recovered patterns.

Abstract: A method and apparatus is provided for mitigating multiband self-interference using multipath cancellation. A dual-band transceiver receives an incoming radio-frequency signal that includes a multipath self-interference component generated by the transmission of an outgoing radio-frequency signal. The transceiver creates a plurality of reference signals from the outgoing radio-frequency signal by introducing delay values with respect to the outgoing signal. The transceiver adjusts the amplitude and phase of each of the delayed reference signals and combines the resulting signals with the incoming radio-frequency signal to cancel the self-interference component. The delay values may be determined adaptively. The systems and methods described herein are particularly useful for dual-band transceivers capable of communicating simultaneously using Long-Term Evolution (LTE) wideband signals and Public-Safety Narrowband (PSNB) signals.

Abstract: A method and apparatus for using erasure to improve signal decoding when data is impacted by an interference event. Embodiments may include receiving in an RF receiver a desired on-channel signal that includes an information signal modulated on to the desired on-channel signal; generating a sampled received signal with an analog-to-digital (A/D) converter; detecting an interference event using an interference detector as well as generating a mask based on the interference event; processing the sampled received signal using the mask to generate decoding data for use by a soft decoder; and, providing the decoding data to the soft decoder.

Abstract: A method and apparatus for using erasure to improve signal decoding when data is impacted by an interference event. Embodiments may include receiving in an RF receiver a desired on-channel signal that includes an information signal modulated on to the desired on-channel signal; generating a sampled received signal with an analog-to-digital (A/D) converter; detecting an interference event using an interference detector as well as generating a mask based on the interference event; processing the sampled received signal using the mask to generate decoding data for use by a soft decoder; and, providing the decoding data to the soft decoder.

Abstract: A radio receiver (100) includes a symbol recovery unit (108) the produces a raw symbol stream (112) and a recovered symbol stream (116). The recovered symbol stream is produced by applying symbol recovery parameters to the raw symbols. The symbol recovery parameters are updated (218) when the symbol recovery parameters used by the symbol recovery unit lack a requisite level of validity and there is a sufficient indication, based on successive instance of sync information using instance-specific recovery parameters, updated recovery parameters are valid.

Abstract: Methods, systems and apparatus are disclosed for using effective radiated transmit power of a base station at a wireless communication device to determine whether the wireless communication device is within uplink transmission range of the base station. The wireless communication device can also use the effective radiated transmit power to adjust transmit power at the wireless communication device and save battery resources. In one implementation, the disclosed embodiments can be applied in a two-way wireless communication system.

Abstract: Methods, systems and apparatus are disclosed for using effective radiated transmit power of a base station at a wireless communication device to perform an automatic roaming method. In one implementation, the disclosed embodiments can be applied in a two-way wireless communication system.

Abstract: A method of reducing error in transmissions received in a receiver is provided. A transmission containing a synchronization signal is inputted through a first filter to a synchronization correlator, to generate a timing error of the synchronization signal. An amount of delay of the synchronization signal sufficient to reduce the timing error is determined. The transmission is delayed by the amount of delay by being passed through at least a second, variable filter whose delay is determined using a stochastic gradient algorithm. The synchronization correlator may also generate a deviation error of the synchronization signal and determine an amount of deviation correction sufficient to reduce the deviation error as well as generating a frequency error of the synchronization signal and determining an amount of frequency correction sufficient to reduce the frequency error.

Abstract: Methods and apparatus are provided for radio link maintenance at a mobile radio in a wireless communication network. The disclosed methods and apparatus help a mobile radio maintain a radio link by regularly monitoring frame synchronization, regularly checking a scrambling sequence of a mobile radio against that of infrastructure equipment, and regularly detecting and/or recovering from fade conditions. In the event the radio link can not be maintained, then the disclosed methods and apparatus will cause the mobile radio to switch to a control channel so that the synchronization, scrambling mismatch and/or fade issues may be corrected. In one implementation, the disclosed methods and apparatus can be implemented at mobile radios in an Association of Public-Safety Communications Officials (APCO) Project 25 (P25) compliant system.

Abstract: A signal is provided to each of nominal, higher and lower primary filters in a receiver. The nominal, higher and lower primary filters have different center frequencies and a bandwidth B1 and bandwidths B2, respectively and a bandwidth offset B0, with B2=B1+B0. Signal recovery is performed on the output of each primary filter to obtain recovered signals and error values each associated with one of the primary filters. Each error value is provided to a secondary and tertiary filter, to generate a signal criterion, and whose output is measured to generate a quality metric, respectively, associated with each recovered signal. The recovered signal associated with the nominal primary filter and any other recovered signal having an associated signal criterion below a threshold value is selected and the selected recovered signal which has the lowest associated quality metric is chosen.

Abstract: A radio receiver (100) includes a symbol recovery unit (108) the produces a raw symbol stream (112) and a recovered symbol stream (116). The recovered symbol stream is produced by applying symbol recovery parameters to the raw symbols. The symbol recovery parameters are updated (218) when the symbol recovery parameters used by the symbol recovery unit lack a requisite level of validity and there is a sufficient indication, based on successive instance of sync information using instance-specific recovery parameters, updated recovery parameters are valid.

Abstract: A method is described to compensate for deviation error in a H-CPM sync or data burst received by a MLSE receiver in a communication device. The deviation error is estimated and matched filter coefficients are adjusted using the estimated deviation error. Metrics are determined for the current state using the adjusted matched filter coefficients. The state having the minimum metric is determined to be the most likely current state. The most likely previous state is similarly determined. The burst is reconstructed backward from the last state to the initial state. The metric is the squared magnitude of the difference between the channel estimate multiplied by the matched filter coefficient associated with one of the possible states and the current state. Timing and frequency errors are compensated for before estimation and correction of the deviation error. Pilot or sync symbols are used in estimating the deviation error.

Abstract: An assignment scheme exploits the Media Access Control (MAC) layer protocol features under various MAC layer call scenarios. In one embodiment, the Hamming distance between pairs of critical Data Units are assigned to codewords with a minimum distance of dmin2=8 bits, thereby increasing the hard decision error correcting capability from 1 bit to 3 bits when deciding between these pairs of Data Units. The method for assigning data unit identification (DUID) codes by a radio operating within a wireless communication system includes determining by the radio whether an expected burst is a 4 Voice Burst with Encryption Synchronization Signaling (4V); when the expected burst is 4V, decoding the DUID within the received burst using an increased minimum distance; and when the expected burst is not 4V, decoding the DUID within the received burst using a minimum distance.