A communication system includes a first physical-layer (PHY) transceiver and a second PHY transceiver. The first PHY transceiver includes (i) a first transmitter and (ii) a first receiver including a first equalizer. The second PHY transceiver includes (i) a second transmitter and (ii) a second receiver including a second equalizer. The first PHY transceiver and the second PHY transceiver are configured to communicate with one another over a full-duplex link, including training the first equalizer on a second training signal transmitted from the second PHY transceiver, and concurrently training the second equalizer on a first training signal transmitted from the first PHY transceiver.

A method includes transmitting, by a transceiver configured to concurrently transmit over multiple transmit paths and receive over multiple receive paths, one or more signals, the transceiver comprising multiple transmit antennas and multiple receive antennas. The method also includes, for at least one of the multiple receive antennas: receiving one or more feedback signals from one or more power amplifiers associated with the one or more transmitted signals; calculating one or more estimated self-interference (SI) signals based on the one or more feedback signals using an equalizer array comprising a predetermined channel model; and subtracting the one or more estimated SI signals from one or more receive signals received at the at least one receive antenna to obtain one or more residual signals.

A method includes transmitting, by a transceiver configured to concurrently transmit over multiple transmit paths and receive over multiple receive paths, one or more signals, the transceiver comprising multiple transmit antennas and multiple receive antennas. The method also includes, for at least one of the multiple receive antennas: applying a transmit path model to one or more transmitted signals to generate one or more transmit path estimates, the transmit path model determined based on multiple analog power amplifiers associated with the multiple transmit paths; calculating one or more estimated self-interference (SI) signals based on the one or more transmit path estimates using an equalizer array comprising a predetermined channel model; and subtracting the one or more estimated SI signals from one or more receive signals received at the at least one receive antenna to obtain one or more residual signals.

Apparatus and methods for phase noise mitigation in wireless systems and networks. In one embodiment, the apparatus and methods provide enhanced wireless services which provide enhanced performance to 5G millimeter wave system entities base stations (gNodeBs) and their backhaul in support of low-latency and high-throughput operation of these components and the network as a whole. In one variant, an enhanced phase noise mitigation mechanism is provided which has a robust performance in operating in very high frequencies such as millimeter wave spectrum. In yet other implementations, the methods and apparatus described herein can be utilized with respect to mobile devices such as between 5G NR millimeter-wave capable UEs and corresponding gNBs.

As 5G, and especially 6G, push into ever-higher frequencies, phase noise presents an increasing problem. Disclosed are procedures and modulation schemes to mitigate phase noise and permit messaging at higher frequencies. Each modulation scheme provides phase-noise immunity by configuring modulation states with large phase acceptance regions. A message element is faulted if its sum-signal amplitude or phase is in an exclusion zone. Modulation schemes with fewer phase levels, more amplitude levels, and very broad phase acceptance regions are necessary for high frequency operation where phase noise dominates. Using allowed states with the maximum amplitude modulation in both branches can provide nearly 90-degree phase acceptance. Requiring that the two branches be equal provides nearly 180-degree phase acceptance. Further requiring that the amplitude levels be positive can provide total phase-noise immunity, with a 360-degree allowable phase range. Embodiments can thereby enable high frequency communication despite phase noise.

A method is disclosed for mitigating phase noise at high frequencies in 5G and 6G. Quadrature modulation schemes, in which orthogonal branches are amplitude modulated, are susceptible to phase noise which rotates the branches, causing demodulation faults. Disclosed is a single-branch reference signal that can mitigate phase noise. The transmitter can transmit a particular resource element having a normal amplitude in one branch, and zero amplitude in the orthogonal branch. The receiver can then measure the amplitudes of the particular resource element as-received (with phase noise), and determine a phase rotation angle according to a ratio of the two branch amplitudes. The receiver can then correct the branch amplitudes of each message element, and thereby negate the effect of the phase noise. The disclosed procedures can thereby make high-frequency, high-reliability communication feasible, at extremely low cost.

A system for receiving multipath signals is disclosed. The system includes an equalizer that includes an input for a received data signal, wherein the received data comprises a first multipath component and a second multipath component. The equalizer further includes a channel impulse response estimator coupled to the input configured to determine one or more channel impulse response (CIR) estimates for the first multipath component and the second multipath component. The equalizer further includes a statistical estimation module coupled to the channel impulse response estimator configured to estimate a state of the first multipath component and the second multipath component based on the one or more channel impulse response estimates. The equalizer further includes a detector coupled to the statistical estimation module configured to detect data from the received data signal based on an estimated future state of the first multipath component and the second multipath component.

An integrated circuit for a receiving link device includes a processing device to detect, using an equalizer of the receiving link device, that a receiver (RX) pre-cursor value is outside of a threshold value based on a target RX tap value. The processing device further generates, based on the detecting, a plurality of tap messages having a plurality of up or down commands to one of decrease or increase a corresponding transmitter (TX) pre-cursor value of a transmitting link device. The processing device further causes the plurality of tap messages to be provided to a local transmitter to be transmitted to the transmitting link device. The plurality of tap messages is to cause the transmitting link device to adjust the corresponding TX pre-cursor value.

In one aspect, a method for wireless communication includes transmitting a first message indicating a precoding matrix identifier configured to identify a particular precoding matrix for precoding by another wireless communication device for at least one future transmission; and receiving a second message indicating information about whether the particular precoding matrix was or will be used for the at least one future transmission. In another aspect, a method for wireless communication includes receiving a first message indicating a precoding matrix identifier configured to identify a particular precoding matrix for precoding by the wireless communication device for at least one future transmission; and transmitting a second message indicating information about whether the particular precoding matrix was or will be used for precoding for the at least one future transmission. Other aspects and features are also claimed and described.

A method for determining an inverse impulse response of a communication channel by means of a PAM receiver comprises the following method steps: switching on the PAM receiver; if a second PAM transceiver is switched on, setting a difference between a clock frequency of the data signal and a sampling frequency of the first PAM transceiver; comparing a symbol that is output by the interpreter with a state that is supplied to the interpreter, and outputting an error value, wherein in each case a symbol associated with a sampling clock is compared with a state associated with the same sampling clock; adapting m filter coefficients of the equalizer to minimize error values; repeating the third method step and the fourth method step until an error limit value is reached.