The present disclosure relates to random access preamble transmission methods, apparatuses, and storage mediums. In one example method, a terminal device determines, based on a target sub-coverage area to which the terminal device belongs in a preset coverage area of a network device, target random access preamble format information corresponding to the target sub-coverage area. Then, the terminal device sends, to the network device on a target time-frequency resource indicated by target random access preamble time-frequency resource information corresponding to the target random access preamble format information, a random access preamble corresponding to the target random access preamble format information.

The present disclosure relates to random access preamble transmission methods, apparatuses, and storage mediums. In one example method, a terminal device determines, based on a target sub-coverage area to which the terminal device belongs in a preset coverage area of a network device, target random access preamble format information corresponding to the target sub-coverage area. Then, the terminal device sends, to the network device on a target time-frequency resource indicated by target random access preamble time-frequency resource information corresponding to the target random access preamble format information, a random access preamble corresponding to the target random access preamble format information.

A ground station processes downlink signals received from respective satellites. The ground station has a plurality of signal conditioning devices each receiving a respective one of the downlink signals and providing a conditioned downlink signal. A plurality of Doppler and/or Delay compensator devices each receive a respective conditioned downlink signal from a respective one of the plurality of signal conditioning devices. The compensator devices conduct Doppler and/or Delay compensation on the received conditioned downlink signal, and provide a compensated downlink signal output. A selector or diversity combiner receives the compensated downlink signal from each of the plurality of Doppler and/or Delay compensators. The selector or diversity combiner selects one of the received compensated downlink signals based on received signal strength of each received compensated downlink signal to provide a selected downlink signal, or diversity combines all of the received compensated downlink signals to provide a diversity combined signal. The selector or diversity combiner provides the selected downlink signal or the diversity combined signal to an eNodeB.

A ground station processes downlink signals received from respective satellites. The ground station has a plurality of signal conditioning devices each receiving a respective one of the downlink signals and providing a conditioned downlink signal. A plurality of Doppler and/or Delay compensator devices each receive a respective conditioned downlink signal from a respective one of the plurality of signal conditioning devices. The compensator devices conduct Doppler and/or Delay compensation on the received conditioned downlink signal, and provide a compensated downlink signal output. A selector or diversity combiner receives the compensated downlink signal from each of the plurality of Doppler and/or Delay compensators. The selector or diversity combiner selects one of the received compensated downlink signals based on received signal strength of each received compensated downlink signal to provide a selected downlink signal, or diversity combines all of the received compensated downlink signals to provide a diversity combined signal. The selector or diversity combiner provides the selected downlink signal or the diversity combined signal to an eNodeB.

Systems and methods are disclosed herein for supporting coherent transmissions in a wireless network such as a Non-Terrestrial Network (NTN). In one embodiment, a method performed by a wireless communication device comprises starting an uplink transmission and performing one or more actions comprising creating a time gap within the uplink transmission and/or muting a portion of the uplink transmission to support a timing advance of the continued uplink transmission. The method further comprises performing time-frequency compensation during a time period created by performing the one or more actions and continuing the uplink transmission after performing the time-frequency compensation. In this manner, a low-complexity method for achieving a compensation for a time variant Doppler shift is provided. This offers a predictability that can be used in a wireless network such as, for example, an NTN for supporting coherent demodulation and optimized receiver implementations.

Systems and methods are disclosed herein for supporting coherent transmissions in a wireless network such as a Non-Terrestrial Network (NTN). In one embodiment, a method performed by a wireless communication device comprises starting an uplink transmission and performing one or more actions comprising creating a time gap within the uplink transmission and/or muting a portion of the uplink transmission to support a timing advance of the continued uplink transmission. The method further comprises performing time-frequency compensation during a time period created by performing the one or more actions and continuing the uplink transmission after performing the time-frequency compensation. In this manner, a low-complexity method for achieving a compensation for a time variant Doppler shift is provided. This offers a predictability that can be used in a wireless network such as, for example, an NTN for supporting coherent demodulation and optimized receiver implementations.

Certain aspects of the present disclosure provide techniques for a synchronization signal block (SSB)-level sleep mode. A method that may be performed by a user equipment (UE) includes determining, from a synchronization signal burst set, a first set of synchronization signal blocks (SSBs) to forgo performing measurements on using one or more receive beams based, at least in part, on one or more previous measurements associated with the determined first set of SSBs and performing measurements on only one or more remaining SSBs in the synchronization signal burst set using the one or more receive beams.

Certain aspects of the present disclosure provide techniques for a synchronization signal block (SSB)-level sleep mode. A method that may be performed by a user equipment (UE) includes determining, from a synchronization signal burst set, a first set of synchronization signal blocks (SSBs) to forgo performing measurements on using one or more receive beams based, at least in part, on one or more previous measurements associated with the determined first set of SSBs and performing measurements on only one or more remaining SSBs in the synchronization signal burst set using the one or more receive beams.

A circuit for suppressing undesired sub-harmonics includes a plurality of mixers, wherein the plurality of mixers are connected in parallel; a plurality of local oscillator signals (LO), wherein each of the plurality of LOs is associated with one of the plurality of mixers; an input to receive a plurality of phases of a driving clock, wherein each of the plurality of phases is a sub-harmonic of the driving clock, and wherein each phase of the driving clock is distributed to one of the plurality of mixers; wherein the plurality of mixers are configured to suppress one or more of the plurality of phases of the driving clock and amplify a desired phase of the driving clock.

A circuit for suppressing undesired sub-harmonics includes a plurality of mixers, wherein the plurality of mixers are connected in parallel; a plurality of local oscillator signals (LO), wherein each of the plurality of LOs is associated with one of the plurality of mixers; an input to receive a plurality of phases of a driving clock, wherein each of the plurality of phases is a sub-harmonic of the driving clock, and wherein each phase of the driving clock is distributed to one of the plurality of mixers; wherein the plurality of mixers are configured to suppress one or more of the plurality of phases of the driving clock and amplify a desired phase of the driving clock.