A transition satellite system which includes a legacy satellite system and a new satellite system that incorporates gateway level transition, satellite level transition and carrier level transition. The transition satellite system allows new satellite systems with user terminals, satellites and gateways to be able to coexist with existing legacy systems allowing a gradual phase-out of legacy user terminals and systems.

An improved air interface for satellite systems such as a 5G-based non-geostationary (NGSO) satellite system. The air interface includes an improved physical interface for efficient operation over NGSO satellite systems. The air interface includes an improved forward link for communicating from the satellite gateway to the user terminal and a return link for communicating from the user terminal to the satellite gateway.

An improved air interface for satellite systems such as a 5G-based non-geostationary (NGSO) satellite system. The air interface includes an improved physical interface for efficient operation over NGSO satellite systems. The air interface includes an improved forward link for communicating from the satellite gateway to the user terminal and a return link for communicating from the user terminal to the satellite gateway.

A wireless device receives access network information indicating an access network type. Based on the access network type, a non-access stratum (NAS) period is selected among: a first value associated with a geostationary earth orbit (GEO) non-terrestrial network (NTN) access network type; and a second value associated with a low earth orbit (LEO) NTN access network type. A NAS procedure is initiated by sending a NAS request message. A start of the NAS period is based on the sending. The NAS procedure is aborted based on an expiry of the NAS period.

A wireless device receives access network information indicating an access network type. Based on the access network type, a non-access stratum (NAS) period is selected among: a first value associated with a geostationary earth orbit (GEO) non-terrestrial network (NTN) access network type; and a second value associated with a low earth orbit (LEO) NTN access network type. A NAS procedure is initiated by sending a NAS request message. A start of the NAS period is based on the sending. The NAS procedure is aborted based on an expiry of the NAS period.

Satellites provide communication between devices such as user terminals (UTs) and ground stations that are connected to points-of-presence (PoP) connected to other networks, such as the Internet. The PoP accepts downstream data addressed to the UT. A representation of the communication resources that are expected to be used to pass the downstream data from the PoP to the UT is determined and executed on one or more processors. The representations may include representations of traffic shapers, modems, and so forth at different points in the network. The representations may consider real-world and simulated feedback data. Within the representation, traffic shaping is employed to determine preshaped data that includes resource metadata designating the communication resources to be used. The preshaped data is passed along to the actual communication resources for subsequent delivery. The preshaping substantially improves performance of constrained communication resources. The preshaped data may be reshaped as real-world conditions change.

Satellites provide communication between devices such as user terminals (UTs) and ground stations that are connected to points-of-presence (PoP) connected to other networks, such as the Internet. The PoP accepts downstream data addressed to the UT. A representation of the communication resources that are expected to be used to pass the downstream data from the PoP to the UT is determined and executed on one or more processors. The representations may include representations of traffic shapers, modems, and so forth at different points in the network. The representations may consider real-world and simulated feedback data. Within the representation, traffic shaping is employed to determine preshaped data that includes resource metadata designating the communication resources to be used. The preshaped data is passed along to the actual communication resources for subsequent delivery. The preshaping substantially improves performance of constrained communication resources. The preshaped data may be reshaped as real-world conditions change.

A satellite communication system leverages the carrier offset detection capability of the demodulator contained in an on-board modem of M&C channel. The modem detects the frequency error Δf, introduced in the signal path from the output of the base station at ground to the output of baseband conversion on the satellite, by analyzing the baseband signal at the baseband conversion to estimate the received carrier f′c and subtracting it the from the expected frequency (fc).

A satellite communication system leverages the carrier offset detection capability of the demodulator contained in an on-board modem of M&C channel. The modem detects the frequency error Δf, introduced in the signal path from the output of the base station at ground to the output of baseband conversion on the satellite, by analyzing the baseband signal at the baseband conversion to estimate the received carrier f′c and subtracting it the from the expected frequency (fc).

A network node is described which is configured for use in space, comprising a transmission interface for transmitting radio frequency signals, a reception interface for receiving radio frequency signals, a network management module for determining communication session information, a controller arranged to control the transmission interface and the reception interface in accordance with session information provided by the network management interface, wherein the transmission and reception interfaces are for receiving data from terrestrial nodes and space-borne nodes. Also described are a network entity comprising the network note and a plurality of adaptive antennas, a satellite containing the network entity and a user equipment device configured for communication with the network node.