Systems and methods are described herein for multi-mode compensation of frequency errors within signals transmitted and received by a mobile terminal. The frequency error can be due to Doppler shift and oscillator error, which introduce opposite frequency shifts. In an acquisition mode, the mobile terminal initially compensates for the oscillator error while transmitting a signal to a communication system that contains the Doppler shift. Upon receiving a message from the communication system indicating the Doppler shift contained in the transmit signal, the mobile terminal can then switch to a tracking mode that can compensate for both Doppler shift and oscillator error.

Systems and methods are described herein for multi-mode compensation of frequency errors within signals transmitted and received by a mobile terminal. The frequency error can be due to Doppler shift and oscillator error, which introduce opposite frequency shifts. In an acquisition mode, the mobile terminal initially compensates for the oscillator error while transmitting a signal to a communication system that contains the Doppler shift. Upon receiving a message from the communication system indicating the Doppler shift contained in the transmit signal, the mobile terminal can then switch to a tracking mode that can compensate for both Doppler shift and oscillator error.

A method for wireless communication in a reflective environment includes (a) receiving first wireless signals at a first antenna assembly at least partially via a first reflective environment, (b) generating a first electrical signal from a first antenna element of the first antenna assembly in response to the first wireless signals, the first antenna element having a first polarization, (c) generating a second electrical signal from a second antenna element of the first antenna assembly in response to the first wireless signals, the second antenna element having a second polarization different from the first polarization, (d) shifting phase of at least one of the first electrical signal and the second electrical signal, and (e) after shifting phase, combining at least the first electrical signal and the second electrical signal to generate a combined electrical signal.

A method for wireless communication in a reflective environment includes (a) receiving first wireless signals at a first antenna assembly at least partially via a first reflective environment, (b) generating a first electrical signal from a first antenna element of the first antenna assembly in response to the first wireless signals, the first antenna element having a first polarization, (c) generating a second electrical signal from a second antenna element of the first antenna assembly in response to the first wireless signals, the second antenna element having a second polarization different from the first polarization, (d) shifting phase of at least one of the first electrical signal and the second electrical signal, and (e) after shifting phase, combining at least the first electrical signal and the second electrical signal to generate a combined electrical signal.

Facilitating sparsity adaptive feedback in the delay doppler domain in advanced networks (e.g., 4G, 5G, 6G, and beyond) is provided herein. Operations of a method can comprise determining, by a first device comprising a processor, a channel covariance matrix in a time-frequency domain based on a channel estimation associated with reference signals received from a second device. The method also can comprise decomposing, by the first device, the channel covariance matrix into a group of component matrices. Further, the method can comprise transforming, by the first device, respective matrices of the group of component matrices into respective covariance matrices in a delay doppler domain. The method also can comprise determining, by the first device, channel state information feedback in the delay doppler domain.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may be configured to estimate a signal-to-noise ratio for each antenna port associated with a reception of one or more tracking reference signals. The UE may receive one or more of multiple single-port tracking reference signals, a single multi-port tracking reference signal, or a tracking reference signal associated with multiple power ratios. The UE may be able to estimate a channel upon receiving a demodulation reference signal. The channel estimation may be based on the reception of one or more of multiple single-port tracking reference signals, the single multi-port tracking reference signal, or the tracking reference signal associated with multiple power ratios. The UE may communicate with the base station based on estimating the channel.

Methods, systems, and devices for wireless communications are described. A user equipment (UE) may be configured to estimate a signal-to-noise ratio for each antenna port associated with a reception of one or more tracking reference signals. The UE may receive one or more of multiple single-port tracking reference signals, a single multi-port tracking reference signal, or a tracking reference signal associated with multiple power ratios. The UE may be able to estimate a channel upon receiving a demodulation reference signal. The channel estimation may be based on the reception of one or more of multiple single-port tracking reference signals, the single multi-port tracking reference signal, or the tracking reference signal associated with multiple power ratios. The UE may communicate with the base station based on estimating the channel.

The disclosed subject matter relates to techniques for determining channel state information (CSI) in New Radio (NR) access communication systems with phase tracking. In one embodiment, a method is provided that comprises receiving, by a device comprising a processer, configuration information from a network device of a wireless communication network indicating that a PTRS protocol has been configured for wireless communications between the device and the network device. The method further comprises, determining, by the device, a resource density of resource elements of the wireless communication network allocated for the phase tracking reference signal protocol, determining, by the device, CSI based on the resource density, and reporting, by the device, the CSI to the network device.

The disclosed subject matter relates to techniques for determining channel state information (CSI) in New Radio (NR) access communication systems with phase tracking. In one embodiment, a method is provided that comprises receiving, by a device comprising a processer, configuration information from a network device of a wireless communication network indicating that a PTRS protocol has been configured for wireless communications between the device and the network device. The method further comprises, determining, by the device, a resource density of resource elements of the wireless communication network allocated for the phase tracking reference signal protocol, determining, by the device, CSI based on the resource density, and reporting, by the device, the CSI to the network device.

An illustrative embodiment disclosed herein is a method including determining, by a location server, a satellite constellation, a location of a target endpoint, and a next available time of the target endpoint. The method further includes determining, by the location server, a plurality of candidate satellites based on the satellite constellation, the location of the target endpoint, and the next available time of the target endpoint. The method further includes instructing, by the location server, a ground station to broadcast a downlink signal to the plurality of candidate satellites.