Methods and systems are described for providing end-to-end beamforming. For example, end-to-end beamforming systems include end-to-end relays and ground networks to provide communications to user terminals located in user beam coverage areas. The ground segment can include geographically distributed access nodes and a central processing system. Return uplink signals, transmitted from the user terminals, have multipath induced by a plurality of receive/transmit signal paths in the end to end relay and are relayed to the ground network. The ground network, using beamformers, recovers user data streams transmitted by the user terminals from return downlink signals. The ground network, using beamformers generates forward uplink signals from appropriately weighted combinations of user data streams that, after relay by the end-end-end relay, produce forward downlink signals that combine to form user beams.

Methods and systems are described for providing end-to-end beamforming. For example, end-to-end beamforming systems include end-to-end relays and ground networks to provide communications to user terminals located in user beam coverage areas. The ground segment can include geographically distributed access nodes and a central processing system. Return uplink signals, transmitted from the user terminals, have multipath induced by a plurality of receive/transmit signal paths in the end to end relay and are relayed to the ground network. The ground network, using beamformers, recovers user data streams transmitted by the user terminals from return downlink signals. The ground network, using beamformers generates forward uplink signals from appropriately weighted combinations of user data streams that, after relay by the end-end-end relay, produce forward downlink signals that combine to form user beams.

Methods and systems are described for providing end-to-end beamforming. For example, end-to-end beamforming systems include end-to-end relays and ground networks to provide communications to user terminals located in user beam coverage areas. The ground segment can include geographically distributed access nodes and a central processing system. Return uplink signals, transmitted from the user terminals, have multipath induced by a plurality of receive/transmit signal paths in the end to end relay and are relayed to the ground network. The ground network, using beamformers, recovers user data streams transmitted by the user terminals from return downlink signals. The ground network, using beamformers generates forward uplink signals from appropriately weighted combinations of user data streams that, after relay by the end-end-end relay, produce forward downlink signals that combine to form user beams.

Methods and systems are described for providing end-to-end beamforming. For example, end-to-end beamforming systems include end-to-end relays and ground networks to provide communications to user terminals located in user beam coverage areas. The ground segment can include geographically distributed access nodes and a central processing system. Return uplink signals, transmitted from the user terminals, have multipath induced by a plurality of receive/transmit signal paths in the end to end relay and are relayed to the ground network. The ground network, using beamformers, recovers user data streams transmitted by the user terminals from return downlink signals. The ground network, using beamformers generates forward uplink signals from appropriately weighted combinations of user data streams that, after relay by the end-end-end relay, produce forward downlink signals that combine to form user beams.

Methods and systems are described for providing end-to-end beamforming. For example, an end-to-end beamforming system include a relay satellite and a ground network to provide communications to user terminals located in user beam coverage areas. The ground network includes geographically distributed access nodes and a central processing system (CPS). Beamformers of the ground network generate forward uplink signals from appropriately weighted combinations of user data streams that, after relay by the satellite, produce forward downlink signals that combine to form forward user beams.

A letter download query method may include a terminal sending a letter download query request packet to a satellite network device, where the letter download query request packet includes a service type field and a message ID field, the service type field indicates a service type of the letter download query request packet, and the message ID field indicates an ID of a letter successfully received by the terminal last time. The terminal receives a letter download query result packet from the satellite network device, where the letter download query result packet includes an original letter sending time field and a letter content field, the original letter sending time field indicates original sending time of letter content in the letter content field, and the letter content field indicates letter content from one or more target terminals to the terminal.

A communication method and apparatus. One method includes: a session management network element obtains an identifier of a DN accessed by a terminal device and/or an identifier of a network slice accessed by the terminal device. The session management network element determines, based on the identifier of the DN and/or the identifier of the network slice, a service type requested by the terminal device. The session management network element requests, from an access network device on a satellite, tunnel information corresponding to the service type. The session management network element receives, from the access network device, the tunnel information corresponding to the service type.

Methods and systems are described for providing end-to-end beamforming. For example, end-to-end beamforming systems include end-to-end relays and ground networks to provide communications to user terminals located in user beam coverage areas. The ground segment can include geographically distributed access nodes and a central processing system. Return uplink signals, transmitted from the user terminals, have multipath induced by a plurality of receive/transmit signal paths in the end to end relay and are relayed to the ground network. The ground network, using beamformers, recovers user data streams transmitted by the user terminals from return downlink signals. The ground network, using beamformers generates forward uplink signals from appropriately weighted combinations of user data streams that, after relay by the end-end-end relay, produce forward downlink signals that combine to form user beams.

Systems and methods for a satellite communication system include identifying highly active terminals (HUTs) in a spot beam of a satellite; determining a first ratio of single-band HUTs that operate in a first frequency band only to multi-band HUTs that operate in the first frequency band and a second frequency band; and determining a second ratio of outroutes for the first frequency band to outroutes for the second frequency band. When the first ratio is less than the second ratio, a first step of balancing the single-band HUTs across the outroutes for the first frequency band is performed, and then the multi-band HUTs are balanced across both the outroutes for the first frequency band and the outroutes for the second frequency band. When the first ratio is greater than the second ratio, the single-band HUTs and the multi-band HUTs are allocated based on at least one weight factor.

Systems and methods for outroute load balancing in a multi-band hybrid satellite communication system include comparing the load metric of each of code rate organizers (CROs) to a threshold value; placing each CRO in one of a surplus load balancing set and a deficit balancing set based on a value of the load metric; and determining a probability metric for each satellite terminal associated with each of the CROs in the surplus load balancing set. The probability metric indicates a probability of the terminal moving to one of the CROs in the deficit load balancing set. At least one satellite terminal associated with one of the CROs in the surplus load balancing set is then caused to switch to one of the CROs in the deficit load balancing set based on the probability metric of the at least one satellite terminal.