According to one or more of the embodiments herein, systems and techniques for using satellite diversity for enhancing communication confidentiality are provided. In particular, a system in accordance with the techniques herein enhances the security of encrypted messages transmitted over a secure channel, specifically through the use of satellite communications diversity to securely deliver secret messages from a sender to a recipient, ensuring message confidentiality. That is, the techniques herein provide secure message communication over satellites, particularly with additional message security in the presence of an eavesdropping adversary party by segmenting the message and sending the various message segments over different diverse paths.

Systems and methods for reliable content delivery from a satellite to sub-edge devices are described. Content is delivered to a plurality of edge devices. Missing portions of the content are identified. One or more of the missing portions are selected, and the selected portions are recovered via a satellite network or a non-satellite network. The recovery is coordinated by a central cloud device based on one or more recovery factors.

A multi-user satellite system provides communication services to external satellites. This satellite system provides in-orbit access points that can be used by the external satellites to offload data instead on relying directly on ground stations. One approach to such communication is to use a set of interface satellites (“converter satellites”) that provide a gateway between a constellation of satellites that together provide communication services to one or more ground stations, but that do not necessarily have the communication capabilities to communicate with external satellites. In this way, the interface satellites can be put in compatible orbits with external satellites and provide communication gateways that can be used to offload data from the external satellites to ground stations. As external satellites change their communication methods, the interface satellites can be reconfigured or new compatible interface satellites can be launched, without having to modify the constellation of satellites.

A satellite constellation forming system (600) forms a satellite constellation which is composed of a satellite group that cooperatively provides a communication service, and has a plurality of orbital planes in each of which a plurality of satellites fly at the same orbital altitude. Each satellite of the satellite group includes inter-satellite communication means and satellite-ground communication means. A satellite constellation forming unit (11) forms the satellite constellation which has ten or more orbital planes with different normal directions, and in which at least one relative angle in an azimuth direction of adjacent orbital planes of the plurality of orbital planes is arranged to be uneven and satellite-ground communication means of satellites flying in orbital planes spaced unevenly have a communication range that achieves complete ground coverage above the equator.

Provided are an information indication method and apparatus and a computer-readable storage medium. The information indication method includes that a first communication node sends first indication information including elevation information and residence information of a beam.

Some implementations describe a method including: receiving, by multiple receivers of multiple gateways of a ground receiver system, from multiple transmitters of a satellite over a downlink of a LoS MIMO feeder link, multiple RF signals; obtaining, at the ground receiver system, from the RF signals, preamble signals and pilot signals including first sequences of pilot symbols associated with second sequences of pilot symbols transmitted by the transmitters; estimating, based on the first sequences of pilot symbols and second sequences of pilot symbols, first channel state information (CSI) of the pilot signals; estimating, using the first CSI, frequency offsets and phase offsets of links between the receivers and the transmitters; adjusting, based at least on the frequency offsets and the phase offsets, the preamble signals to obtain adjusted preamble signals; and estimating, at the ground receiver system, using the adjusted preamble signals, second CSI of the downlink.

According to an example aspect of the present invention, there is provided an apparatus comprising at least one processing core, at least one memory including computer program code, the at least one memory and the computer program code being configured to, with the at least one processing core, cause the apparatus at least to receive, from a first beam, information concerning frequency adjustment of a second beam, the second beam being different from the first beam, and apply the information when synchronizing with the second beam, and/or in transmitting to the second beam in an uplink transmission.

A satellite communication system with software defined network orchestration. Implementations include a route management function (RMF) that receives link status from the satellites and determines simple routing tables which are uploaded to the satellites. The routing tables allow the satellites to route data based on a satellite ID placed in a data header to reduce the memory and computing load on satellite resources. Further, implementations include secure user terminal (UT) to UT IP routing in the constellation for direct UT to UT communication. The satellite communication system may combine the benefits of Medium Earth Orbit (MEO) and Low Earth Orbit (LEO) satellite systems into an MEO-LEO satellite system.

A user equipment (UE) is configured to receive broadcast information from a public land mobile network (PLMN) including at least a PLMN identifier (ID), attempt a registration with the PLMN by sending a registration request to the PLMN, wherein the UE attempts the registration via a base station operated by the PLMN deployed in a non-terrestrial network (NTN) arrangement including a non-terrestrial component configured to provide services to the UE via a service link, receive a message including a cause code indicating the PLMN is not allowed to operate at a current UE location and further including a set of attributes indicating further conditions wherein the registration with the PLMN is not allowed and avoid further registration attempts with the PLMN when the further conditions are met.

A device in a population of devices arranged at a celestial body for transmitting data to a relay station orbiting the celestial body. The relay station and the population of devices are to travel with respect to one another such that the relay station is to receive signals that include the data in data packages from the population of devices. The device includes trajectory data of the relay station, a transmitter to use the trajectory data so as to transmit a signal that is part of the signals, a data processor, and a computer program which, when executing on the data processor, is to calculate a Doppler shift based upon the trajectory data, and modify the signal to thereby compensate for the Doppler shift of the signal that results from the travelling of the relay station and the population of devices with respect to one another.