A system may include a transmitter node and a receiver node. Each node may include a communications interface including at least one antenna element and a controller operatively coupled to the communications interface, the controller including one or more processors, wherein the controller has information of own node velocity and own node orientation. Each node of the transmitter node and the receiver node may be in motion relative to each other. Each node may be time synchronized to apply Doppler corrections associated with said node's own motions relative to a common reference frame. The common reference frame may be known to the transmitter node and the receiver node prior to the transmitter node transmitting signals to the receiver node and prior to the receiver node receiving the signals from the transmitter node. The receiver node may be configured to be in a state of reduced emissions.

A system and method for determining SFN using QCL information is disclosed. In one aspect, a method receiving, by a wireless communication device, a first set of quasi-co-location (QCL) information; receiving, by the wireless communication device, a transmission; and applying, by the wireless communication device, a second set of QCL information based on the first set of QCL information, wherein the second set of QCL information is different from the first set of QCL information.

A system and method for determining SFN using QCL information is disclosed. In one aspect, a method receiving, by a wireless communication device, a first set of quasi-co-location (QCL) information; receiving, by the wireless communication device, a transmission; and applying, by the wireless communication device, a second set of QCL information based on the first set of QCL information, wherein the second set of QCL information is different from the first set of QCL information.

Systems and methods for Doppler frequency shift compensation in free space optical links include a modulator configured to modulate a transmitter laser; a receiver including a Local Oscillator (LO) laser configured to receive a coherent signal; and circuitry configured to tune a frequency of the transmitter laser and the LO laser based on an amount of Doppler frequency shift to be compensated. The systems and methods determine an amount of Doppler shift between a first and second satellite and tune the frequency of the transmitter and LO laser based on the determined amount of Doppler frequency shift.

Systems and methods for Doppler frequency shift compensation in free space optical links include a modulator configured to modulate a transmitter laser; a receiver including a Local Oscillator (LO) laser configured to receive a coherent signal; and circuitry configured to tune a frequency of the transmitter laser and the LO laser based on an amount of Doppler frequency shift to be compensated. The systems and methods determine an amount of Doppler shift between a first and second satellite and tune the frequency of the transmitter and LO laser based on the determined amount of Doppler frequency shift.

In some aspects of the disclosure, an apparatus for wireless communication by a user equipment (UE) includes a primary receive (PRx) path associated with a first antenna and configured to receive a wireless signal. The apparatus further includes a diversity receive (DRx) path associated with a second antenna antenna. The apparatus further includes a phase shifter configured to phase-modify an interference signal from the second antenna based at least in part on a physical distance between the first antenna and the second antenna and further based on an angle of arrival (AoA) associated with the interference signal. The apparatus further includes a circuit configured to generate a received signal based on the wireless signal and the phase-modified interference signal.

In some aspects of the disclosure, an apparatus for wireless communication by a user equipment (UE) includes a primary receive (PRx) path associated with a first antenna and configured to receive a wireless signal. The apparatus further includes a diversity receive (DRx) path associated with a second antenna antenna. The apparatus further includes a phase shifter configured to phase-modify an interference signal from the second antenna based at least in part on a physical distance between the first antenna and the second antenna and further based on an angle of arrival (AoA) associated with the interference signal. The apparatus further includes a circuit configured to generate a received signal based on the wireless signal and the phase-modified interference signal.

Doppler effects are compensated for in received wireless communication signals. In a receiver a first signal is received, that was transmitted by a transmitter at a first frequency f.sub.1 and that was received at a doppler-shifted first frequency f.sub.1 and a second signal, that was transmitted by said transmitter at a second frequency f.sub.2 and that was received at a doppler-shifted second frequency f.sub.2 is also received. A frequency difference f.sub.S between the first frequency f.sub.1 and the second frequency f.sub.2 has a predetermined value. Based on the doppler-shifted first frequency f.sub.1, the doppler-shifted second frequency f.sub.2 and the frequency difference f.sub.S, the first frequency f.sub.1 is determined for pre-compensating Doppler effects in the received first signal.

Doppler effects are compensated for in received wireless communication signals. In a receiver a first signal is received, that was transmitted by a transmitter at a first frequency f.sub.1 and that was received at a doppler-shifted first frequency f.sub.1 and a second signal, that was transmitted by said transmitter at a second frequency f.sub.2 and that was received at a doppler-shifted second frequency f.sub.2 is also received. A frequency difference f.sub.S between the first frequency f.sub.1 and the second frequency f.sub.2 has a predetermined value. Based on the doppler-shifted first frequency f.sub.1, the doppler-shifted second frequency f.sub.2 and the frequency difference f.sub.S, the first frequency f.sub.1 is determined for pre-compensating Doppler effects in the received first signal.

A communication device providing CSI feedback in a wireless communication system includes a transceiver to receive downlink reference signals and downlink signals including a reference signal configuration. A processor estimates an explicit CSI in the frequency domain. The processor selects a Doppler-delay-beam precoder matrix for a composite Doppler-delay-beam three-stage precoder, which is based on one or more codebooks including one or more transmit-side spatial beam components, one or more delay components, and one or more Doppler-frequency components,
The processor calculates a CQI and/or a PMI and/or a rank indicator, RI, using the explicit CSI and the composite Doppler-delay-beam three-stage precoder, and reports the CSI feedback including the CQI, and/or the PMI and/or the RI. The one or more delay and/or Doppler-frequency components are defined by one or more sub-matrices of a DFT matrix or an oversampled DFT matrix.