Abstract: A wireless radio transceiver system configured to transmit and receive a communications signal waveform having a time division multiple access physical layer structure and which includes a sequence of orthogonal frequency division multiple access symbols. The transceiver provides transmit diversity through space-time coding and the use of orthogonal channel probes from each transmitter. The waveform is packet based and contains a packet header definition that supports local receiver synchronization. Examples of the waveform also incorporate transmission security features.

Abstract: A method and apparatus to select bits for puncturing forward error correcting code frames to synthesize higher code rates. For example, there is provided a method of puncturing a digital data stream that includes a first parity bit stream and a second parity bit stream to generate a punctured bit stream. In one example, the method includes operating a first counting loop to select a first number of punctured bits from the first parity bit stream, comparing the first number of punctured bits with a desired number of bits for the punctured bit stream, and if the first number of punctured bits is less than the desired number of bits, operating a second counting loop to select a second number of punctured bits from the second parity bit stream until the sum of the first number of punctured bits and the second number of punctured bits is equal to the desired number of bits for the punctured bit stream.

Abstract: A wireless communication system in which each receiver is configured synchronize to a received waveform using only its local received signal without requiring any information about other receivers in the system. The local receiver is configured to remove frequency and/or phase error based on information encoded in the received waveform. In some examples, the local receiver uses channel probe information embedded in the received waveform to provide channel estimates for each communication channel over which the signals are received and, based on the estimates, adjusts the received signals for phase shift and amplitude scaling caused by the channel. Signal acquisition (in time and frequency), as well as partial demodulation (for channel estimation), is done independently for each channel. Signals from each channel are combined using a maximal ratio combiner.

Abstract: A wireless radio transceiver system configured to transmit and receive a communications signal waveform having a time division multiple access physical layer structure and which includes a sequence of orthogonal frequency division multiple access symbols. The transceiver provides transmit diversity through space-time coding and the use of orthogonal channel probes from each transmitter. The waveform is packet based and contains a packet header definition that supports local receiver synchronization. Examples of the waveform also incorporate transmission security features.

Abstract: A wireless communication system in which each receiver is configured synchronize to a received waveform using only its local received signal without requiring any information about other receivers in the system. The local receiver is configured to remove frequency and/or phase error based on information encoded in the received waveform. In some examples, the local receiver uses channel probe information embedded in the received waveform to provide channel estimates for each communication channel over which the signals are received and, based on the estimates, adjusts the received signals for phase shift and amplitude scaling caused by the channel. Signal acquisition (in time and frequency), as well as partial demodulation (for channel estimation), is done independently for each channel. Signals from each channel are combined using a maximal ratio combiner.

Abstract: Reducing the peak-to-average power ratio of a signal comprises receiving the input signal, where the input signal is associated with at least one unacceptable frequency range. The input signal is clipped about an amplitude range to yield a clipped signal and clipped information, where the clipped information represents intermodulation products. The clipped information is filtered to yield an error signal. The error signal represents a subset of the intermodulation products, where an intermodulation product of the subset corresponds to the unacceptable frequency range. The error signal is subtracted from the input signal to yield an output signal.

Abstract: Reducing the peak-to-average power ratio of a signal comprises receiving the input signal, where the input signal is associated with at least one unacceptable frequency range. The input signal is clipped about an amplitude range to yield a clipped signal and clipped information, where the clipped information represents intermodulation products. The clipped information is filtered to yield an error signal. The error signal represents a subset of the intermodulation products, where an intermodulation product of the subset corresponds to the unacceptable frequency range. The error signal is subtracted from the input signal to yield an output signal.