Disclosed are a downlink signal processing method and apparatus, a base station, and a non-transitory computer-readable medium. The downlink signal processing method may includes performing resource element mapping on an unmodulated downlink signal, and performing modulation on the downlink signal that has been subjected to the resource element mapping to obtain modulated data.

Disclosed are a downlink signal processing method and apparatus, a base station, and a non-transitory computer-readable medium. The downlink signal processing method may includes performing resource element mapping on an unmodulated downlink signal, and performing modulation on the downlink signal that has been subjected to the resource element mapping to obtain modulated data.

A signal modulation apparatus, a memory storage apparatus, and a signal modulation method are disclosed. The signal modulation apparatus includes an observation circuit, a signal modulation circuit, and a phase control circuit. The signal modulation circuit is configured to generate a second signal according to a first signal and a reference clock signal. A frequency of the first signal is different from a frequency of the second signal. The phase control circuit is configured to obtain an observation information via the observation circuit. The observation information reflects a process variation of at least one electronic component in the signal modulation apparatus. The phase control circuit is further configured to control an offset between the first signal and the reference clock signal according to the observation information.

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.

Embodiments of a User Equipment (UE) and methods for communication are generally described herein. The UE may be configured for carrier aggregation using a primary component carrier (CC) and a secondary CC. The UE may attempt to detect a sidelink synchronization signal (SLSS) from another UE on the primary CC. The UE may, if the SLSS from the other UE is detected: determine, based on the detected SLSS, a common time synchronization for the primary CC and the secondary CC for vehicle-to-vehicle (V2V) sidelink transmissions in accordance with the carrier aggregation. The UE may, if the SLSS from the other UE is not detected: transmit an SLSS to enable determination of the common time synchronization for the primary CC and the secondary CC by the other UE. The SLSS may be transmitted on the primary CC.

Embodiments of a User Equipment (UE) and methods for communication are generally described herein. The UE may be configured for carrier aggregation using a primary component carrier (CC) and a secondary CC. The UE may attempt to detect a sidelink synchronization signal (SLSS) from another UE on the primary CC. The UE may, if the SLSS from the other UE is detected: determine, based on the detected SLSS, a common time synchronization for the primary CC and the secondary CC for vehicle-to-vehicle (V2V) sidelink transmissions in accordance with the carrier aggregation. The UE may, if the SLSS from the other UE is not detected: transmit an SLSS to enable determination of the common time synchronization for the primary CC and the secondary CC by the other UE. The SLSS may be transmitted on the primary CC.

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 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 coding and modulation apparatus and method are presented. The apparatus comprises an encoder that encodes input data into cell words, and a modulator that modulates said cell words into constellation values of a non-uniform constellation. The modulator is configured to use, based on the total number M of constellation points of the constellation and the code rate, a non-uniform constellation from one or several groupsof constellations each comprising one or more constellations.

A coding and modulation apparatus and method are presented. The apparatus comprises an encoder that encodes input data into cell words, and a modulator that modulates said cell words into constellation values of a non-uniform constellation. The modulator is configured to use, based on the total number M of constellation points of the constellation and the code rate, a non-uniform constellation from one or several groupsof constellations each comprising one or more constellations.