A reference time associated with a satellite signal received at a clock synchronization source is determined, wherein the reference time is from a master reference clock. A recorded time associated with a corresponding satellite signal received at a remote clock synchronization destination is received from the remote clock synchronization destination via a network, wherein the received recorded time is from a remote clock to be synchronized with the master reference clock. A clock adjustment value is calculated based on a comparison of the determined reference time and the received recorded time. The clock adjustment value is provided to the remote clock synchronization destination, wherein the clock adjustment value is able to be utilized by the remote clock synchronization destination to adjust the remote clock to increase synchronization with the master reference clock.

Various solutions for uplink synchronization in non-terrestrial network (NTN) communications are proposed. An apparatus implemented in a user equipment (UE) receives a system information block (SIB) of a target cell via a non-terrestrial (NT) network node of the NTN. The apparatus obtains an explicit epoch time from the SIB of the target cell. Then, the apparatus performs an uplink (UL) synchronization with the target cell through adjusting an uplink transmit time according to the explicit epoch time.

Various solutions for uplink synchronization in non-terrestrial network (NTN) communications are proposed. An apparatus implemented in a user equipment (UE) receives a system information block (SIB) of a target cell via a non-terrestrial (NT) network node of the NTN. The apparatus obtains an explicit epoch time from the SIB of the target cell. Then, the apparatus performs an uplink (UL) synchronization with the target cell through adjusting an uplink transmit time according to the explicit epoch time.

A system for providing air traffic control within a geographic sector to which a communication frequency in the VHF or UHF range is assigned comprises at least one satellite (configured for a communication with an aircraft in the geographic sector using an analog modulated RFF signal at the communication frequency. The system is configured in such a way that at each time, only one satellite is actively transmitting on the communication frequency assigned to the geographic sector.

A system for providing air traffic control within a geographic sector to which a communication frequency in the VHF or UHF range is assigned comprises at least one satellite (configured for a communication with an aircraft in the geographic sector using an analog modulated RFF signal at the communication frequency. The system is configured in such a way that at each time, only one satellite is actively transmitting on the communication frequency assigned to the geographic sector.

An orbiting multiple access transceiver communicates with terrestrial mobile stations which are also capable of communicating with terrestrial base stations. The multiple access transceiver is configured to sample a signal when a terrestrial mobile station of interest is not transmitting to produce a sample signal. The sample signal may be processed to produce an out-of-phase signal that may be applied to a signal when the terrestrial mobile station of interest is transmitting to produce a clearer signal from the terrestrial mobile station of interest.

An orbiting multiple access transceiver communicates with terrestrial mobile stations which are also capable of communicating with terrestrial base stations. The multiple access transceiver is configured to sample a signal when a terrestrial mobile station of interest is not transmitting to produce a sample signal. The sample signal may be processed to produce an out-of-phase signal that may be applied to a signal when the terrestrial mobile station of interest is transmitting to produce a clearer signal from the terrestrial mobile station of interest.

A system to reduce a count of satellite gateways is disclosed. The system includes: a feeder link capacity of a satellite; a spectrum ranging from 26.5 GHz to 75 GHz; a gateway feeder link capacity that is an aggregate of capacities of channels defined in the spectrum; and RF gateways communicating with the satellite via the channels, wherein the count of the satellite gateways is less than or equal to a rounded-up integer of the feeder link capacity divided by the gateway feeder link capacity, and the satellite is a geosynchronous orbit satellite.

A system to reduce a count of satellite gateways is disclosed. The system includes: a feeder link capacity of a satellite; a spectrum ranging from 26.5 GHz to 75 GHz; a gateway feeder link capacity that is an aggregate of capacities of channels defined in the spectrum; and RF gateways communicating with the satellite via the channels, wherein the count of the satellite gateways is less than or equal to a rounded-up integer of the feeder link capacity divided by the gateway feeder link capacity, and the satellite is a geosynchronous orbit satellite.

Certain aspects of the present disclosure provide techniques for communicating user equipment (UE) capability information in wireless communication networks. An exemplary method performed by a UE includes receiving, from a network entity, a request for capability of the UE and transmitting, in response to the request, a UE capability message that differentiates sets of features the UE supports in different network types.