Abstract: In some examples, a binary bit stream of input bits is encoded into a three-amplitude bipolar symbol stream of symbols, the encoding using a coding rule that specifies setting a value of a respective symbol of the symbol stream based on a respective input bit of the binary bit stream and a prior input bit of the binary bit stream that is prior to the respective input bit, the coding rule further specifying that adjacent non-zero pulses keep the same polarity. A radio frequency (RF) carrier signal is modulated using the symbol stream to produce a modulated RF signal.

Abstract: In some examples, a binary bit stream of input bits is encoded into a three-amplitude bipolar symbol stream of symbols, the encoding using a coding rule that specifies setting a value of a respective symbol of the symbol stream based on a respective input bit of the binary bit stream and a prior input bit of the binary bit stream that is prior to the respective input bit, the coding rule further specifying that adjacent non-zero pulses keep the same polarity. A radio frequency (RF) carrier signal is modulated using the symbol stream to produce a modulated RF signal.

Abstract: A method and apparatus for orthogonal frequency division multiplexing (OFDM) modulation includes separating a frequency-domain sequence of complex numbers into a first portion and a second portion that is disjoint with the first portion, each of the first portion and the second portion including a respective half of the complex numbers of the frequency-domain sequence, and generating a time-domain sequence having a real in-phase component that is a function of the first portion only, and an imaginary quadrature-phase component that is a function of the second portion only.

Abstract: In some examples, an apparatus includes a transmitter configured to apply input data as a frequency-domain data sequence to modulate a set of subcarriers, and separate the frequency-domain data sequence into a first subsequence of elements and a second subsequence of elements. A first conjugate symmetric subsequence that is based on inserting a zero value into the first subsequence is formed, and a second conjugate symmetric subsequence that is based on inserting a zero value into the second subsequence is formed, where the zero values are inserted at different positions in the first and second subsequences. A time-domain sequence comprising a first component that is a function of the first conjugate symmetric subsequence, and a second component that is a function of the second conjugate symmetric subsequence is generated.

Abstract: A method and apparatus for orthogonal frequency division multiplexing (OFDM) modulation includes separating a frequency-domain sequence of complex numbers into a first portion and a second portion that is disjoint with the first portion, each of the first portion and the second portion including a respective half of the complex numbers of the frequency-domain sequence, and generating a time-domain sequence having a real in-phase component that is a function of the first portion only, and an imaginary quadrature-phase component that is a function of the second portion only.

Abstract: A method in a network access equipment is provided. The method includes defining a burst duration for sending a plurality of reference signals. The method further includes determining an interval between ones of the plurality of reference signals in the burst duration. The method further includes defining a burst period for sending a plurality of reference signal bursts. The method further includes sending a reference signal instruction message containing an activation message and at least one of the burst duration, the interval, and the burst period.

Abstract: Embodiments are directed to providing communication between a first device and a second device by: iterating, by the first device, over a number of transmitter antenna polarization types in the first device, constructing, by the first device, a number of data units based on each of the transmitter antenna polarization types, transmitting, by the first device, each of the data units for each of a number of receiver antenna polarization types in the second device, receiving, by the first device, an indication of a transmitter antenna polarization type in the first device included in the number of transmitter antenna polarization types in the first device, and transmitting, by the first device, data using the indicated transmitter antenna polarization type.

Abstract: The present disclosure relates generally to systems and methods for timing synchronization. Uplink synchronization is a necessary component of a UE operating in a mobile, wireless network. Reliable uplink synchronization generally requires regular uplink transmission containing reference signals. A method is provided that defines a burst period for sending the reference signals, determines an interval between the reference signals, and sends a timing instruction message that includes the burst period and the determined interval. A second method is provided that receives the timing instruction message and sends the reference signals in accordance with the timing instruction.

Abstract: A method and apparatus for tracking and mitigating phase noise in a communication receiver are disclosed. The phase noise tracking and mitigation apparatus operates in a recursive manner and includes a quantizer for determining data symbols from noise-compensated input values, a phase noise estimator for determining raw phase noise values from the data symbols and a first sequence of uncompensated input values, an error concealment module for removing unreliable samples from the raw phase noise values, a filter operable to filter the raw phase noise values to produce filtered phase noise values, and a phase-noise compensator for determining noise-compensated output values dependent upon the filtered phase noise values and the first sequence of uncompensated input values. Filter coefficients, and initial noise-compensated input values are determined from one or more second sequences of uncompensated input values corresponding to known symbols corrupted by phase noise.

Abstract: A user equipment and a wireless radio frequency assistant in a communication system that supports multiple input multiple output. The wireless radio frequency assistant and the user equipment operate together as a single system. The user equipment controls and activates the wireless radio frequency assistant to transform a first frequency of a radio frequency signal transmitted to the system of user equipment and the wireless radio frequency assistant to a second frequency. The wireless radio frequency assistant transmits the second frequency to the user equipment.

Abstract: The present disclosure provides for a method and apparatus for efficient cross-correlation between a reference sequence and a received sequence in a wireless communication system. The reference sequence includes a concatenation of sign-adjusted sub-sequences, the sign adjustments determined by a first sign sequence of a set of sign sequences. For example, the reference sequence may be an alternating concatenation of sign-adjusted Golay complementary pair sub-sequences. The received sequence is shifted to provide a plurality of time shifted sequences that are then cross-correlated with the sub-sequences to form a set of partial cross-correlations. The partial cross-correlations are sign-adjusted using the first sign sequence and combined to produce the cross-correlation between the reference sequence and the received sequence. The cross-correlations so produced may be used for channel signature (e.g. PHY-type) identification and/or channel impulse response estimation.

Abstract: A method and apparatus for tracking and mitigating phase noise in a communication receiver are disclosed. The phase noise tracking and mitigation apparatus operates in a recursive manner and includes a quantizer for determining data symbols from noise-compensated input values, a phase noise estimator for determining raw phase noise values from the data symbols and a first sequence of uncompensated input values, an error concealment module for removing unreliable samples from the raw phase noise values, a filter operable to filter the raw phase noise values to produce filtered phase noise values, and a phase-noise compensator for determining noise-compensated output values dependent upon the filtered phase noise values and the first sequence of uncompensated input values. Filter coefficients, and initial noise-compensated input values are determined from one or more second sequences of uncompensated input values corresponding to known symbols corrupted by phase noise.

Abstract: In some implementations, a method of a receiver includes receiving an M-ary differential phase-shift keying (DPSK) signal containing a phase offset and optionally a phase rotation. The phase offset of the received signal may be estimated. A soft detection metric employing the estimated phase offset may be calculated to provide enhanced receiver performance. The method may include subtracting the phase offset estimate from the received signal prior to calculating the soft detection metric and/or de-rotating the phase of the received signal by the same amount of the phase rotation prior to estimating the phase offset of the received signal. Estimating the phase offset may be based on maximum likelihood principle. The soft detection metric may be a log-likelihood ratio (LLR) for soft detection of the received M-ary DPSK signal and the calculation of the LLR may be based upon a conditional joint probability density function of two consecutively received symbols.

Abstract: The present disclosure provides for the construction and use of a set of Zero-Correlation-Zone (ZCZ) Concatenated Complementary Pair (CCP) sequences with zero-correlation-zone range greater than one or with zero-correlation-zone range equal to one and the sequence set size greater than two. Complementary pair sequences A and B are selected and, for each member of the set of ZCZ CCP sequences, sign sequences pA and pB are combined with the complementary pair sequences to form a member ZCZ CCP sequence of the set. A ZCZ CCP sequence modified by propagation over a communication channel may be identified by cross-correlation with ZCZ CCP sequences of the set. A set of sign sequences may be constructed by recursive expansion from an initial set or found by a computer search. The sequences may be used in a transceiver of a portable electronic device or other communication device.

Abstract: The present disclosure provides for a method and apparatus for efficient cross-correlation between a reference sequence and a received sequence in a wireless communication system. The reference sequence includes a concatenation of sign-adjusted sub-sequences, the sign adjustments determined by a first sign sequence of a set of sign sequences. For example, the reference sequence may be an alternating concatenation of sign-adjusted Golay complementary pair sub-sequences. The received sequence is shifted to provide a plurality of time shifted sequences that are then cross-correlated with the sub-sequences to form a set of partial cross-correlations. The partial cross-correlations are sign-adjusted using the first sign sequence and combined to produce the cross-correlation between the reference sequence and the received sequence. The cross-correlations so produced may be used for channel signature (e.g. PHY-type) identification and/or channel impulse response estimation.

Abstract: Systems and methods of performing ASK or QAM modulation with uneven distance between symbols are provided. Different bit positions mapped to such symbols are assigned to different receivers, with the result that there are different BER performances among bits sent from a transmitter to the different receivers. Bits for multiple receivers are mapped to a UASK constellation or a UQAM constellation without using superposition.

Abstract: Systems and methods of performing ASK or QAM modulation with uneven distance between symbols are provided. These are used to provide differing BER performances among bits sent from a transmitter to a receiver.

Abstract: Embodiments are directed to providing communication between a first device and a second device by: iterating, by the first device, over a number of transmitter antenna polarization types in the first device, constructing, by the first device, a number of data units based on each of the transmitter antenna polarization types, transmitting, by the first device, each of the data units for each of a number of receiver antenna polarization types in the second device, receiving, by the first device, an indication of a transmitter antenna polarization type in the first device included in the number of transmitter antenna polarization types in the first device, and transmitting, by the first device, data using the indicated transmitter antenna polarization type.

Abstract: An OFDM system and method using amplitude shift keying (ASK) for subcarrier modulation is provided. Because ASK is used, the signal of each symbol in time domain is conjugate-symmetric. In addition, among the discrete numbers of each symbol, two of them are always real. These properties are utilized such that only half of the numbers of each symbol sequence are transmitted. The generated baseband signal can be a complex or a real signal. As a result, the bandwidth efficiency of the derived ASK-OFDM is the same as that of QAM-OFDM.

Abstract: The present disclosure provides for a method and apparatus for efficient cross-correlation between a reference sequence and a received sequence in a wireless communication system. The reference sequence includes a concatenation of sign-adjusted sub-sequences, the sign adjustments determined by a first sign sequence of a set of sign sequences. For example, the reference sequence may be an alternating concatenation of sign-adjusted Golay complementary pair sub-sequences. The received sequence is shifted to provide a plurality of time shifted sequences that are then cross-correlated with the sub-sequences to form a set of partial cross-correlations. The partial cross-correlations are sign-adjusted using the first sign sequence and combined to produce the cross-correlation between the reference sequence and the received sequence. The cross-correlations so produced may be used for channel signature (e.g. PHY-type) identification and/or channel impulse response estimation.