Abstract: This disclosure relates to techniques for performing ranging wireless communication in a secure manner. A first wireless device may receive a plurality of independent sequences from a second wireless device. The first wireless device may perform a combined channel estimate using the sequences. The first wireless device may estimate the distance (or angle/direction, among various possibilities) between the two devices based on the combined channel estimate.

Abstract: This disclosure relates to techniques for performing ranging wireless communication in a secure manner. A first wireless device may receive a plurality of independent sequences from a second wireless device. The first wireless device may perform a combined channel estimate using the sequences. The first wireless device may estimate the distance (or angle/direction, among various possibilities) between the two devices based on the combined channel estimate.

Abstract: A method for performing measurement by a radio apparatus is presented. In one embodiment, the method includes determining raw measurements (e.g., a channel estimation and a noise variance estimation) of a subband and determining a rank indicator (RI) without requiring a precoding matrix indicator (PMI) search. The method includes calculating, based at least on the raw measurements, a mean instantaneous capacity (MIC) for the subband and determining a channel quality indicator (CQI) and a PMI based at least on the MIC. In one embodiment, the method uses subband-based measurements for performing feedback/measurement.

Abstract: A method for conveying digital data from a transmitter (20) to a receiver (40) includes specifying a spectral filtering profile to be applied in conveying the data. A sequence of input symbols is generated (22) at the transmitter, corresponding to the data to be conveyed. The input symbols are precoded at the transmitter using Tomlinson-Harashima precoding (25) responsive to the specified profile, so as to generate a corresponding sequence of precoded symbols. The precoded symbols are filtered (26) in accordance with the specified profile. The precoded and filtered symbols are decoded at the receiver so as to recover the data therefrom.

Abstract: A method for conveying digital data from a transmitter to a receiver includes specifying a spectral filtering profile to be applied in conveying the data. A sequence of input symbols is generated at the transmitter, corresponding to the data to be conveyed. The input symbols are precoded at the transmitter using Tomlinson-Harashima preceding responsive to the specified profile, so as to generate a corresponding sequence of precoded symbols. The precoded symbols are filtered in accordance with the specified profile. The precoded and filtered symbols are decoded at the receiver so as to recover the data therefrom.

Abstract: A method for decoding a sequence of symbols encoded by an encoding system with a plurality of possible states and transmitted over a channel, wherein the encoding system output can be represented by a trellis diagram. The method includes receiving a signal corresponding to the sequence of symbols transmitted over the channel and responsive to the signal, finding respective old state metrics for one or more of the possible states of the encoding system that correspond to a given symbol in the sequence. Respective transition metrics are determined for state transitions that link the one or more possible states for which the old state metrics were found to at least some of the possible states of the encoding system that correspond to a succeeding one of the symbols in the sequence.

Abstract: A digital data receiver includes a front end, coupled to receive an input signal transmitted over a communication channel, the signal representing a stream of transmitted symbols with a given input symbol rate, and to generate, responsive to the input signal, a stream of received samples at a processing rate that is a non-integer rational multiple of the input symbol rate. A feed-forward equalizer receives input samples at the processing rate, responsive to the received samples, and generates forward-equalized samples at the input symbol rate. Decision circuitry processes the forward-equalized samples so as to generate a stream of estimated symbols at the input symbol rate.

Abstract: A digital data receiver, for receiving a signal that is transmitted over a channel having a channel response and is filtered with a predetermined filter response. The receiver includes a decision device, coupled to receive a sequence of equalized samples and to generate, responsive thereto, a corresponding sequence of estimated symbols. A feed-forward equalizer receives a sequence of input samples of the signal and generates responsive to the input samples, forward-equalized samples. A decision feedback equalizer (DFE), which receives the sequence of estimated symbols, includes an adaptive element, which processes the estimated symbols responsive to the channel response, and a fixed element, which processes the estimated symbols responsive to the predetermined filter response. The DFE generates feedback-equalized samples by combined operation of the adaptive and fixed elements.

Abstract: A method for conveying digital data from a transmitter (20) to a receiver (40) includes specifying a spectral filtering profile to be applied in conveying the data. A sequence of input symbols is generated (22) at the transmitter, corresponding to the data to be conveyed. The input symbols are precoded at the transmitter using Tomlinson-Harashima precoding (25) responsive to the specified profile, so as to generate a corresponding sequence of precoded symbols. The precoded symbols are filtered (26) in accordance with the specified profile. The precoded and filtered symbols are decoded at the receiver so as to recover the data therefrom.