The orbital states (position and/or time) for a constellation of space vehicles is determined as follows. The space vehicles measure PNT data, including range data determined based on FSO links between the space vehicles. The PNT data is transmitted from the space vehicles to two or more PNT controllers, which are a subset of the space vehicles that calculate the orbital state data for the constellation. This is a semi-distributed calculation. There is not a single controller that performs the calculations for all of the space vehicles in the constellation, and it is also not the case that each space vehicle performs its own calculations. Rather, each PNT controller services a sub-constellation of the space vehicles and determines the orbital state data for the space vehicles in the sub-constellation. The calculated orbital state data is transmitted from the PNT controllers to the space vehicles in the corresponding sub-constellations.

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.

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.

Methods for a New Radio (NR)-based, Low Earth Orbit (LEO) Non-Terrestrial Networks (NTN) are proposed to improve cell selection and reselection by using satellite assistance information. Different from traditional 5G New Radio systems, the LEO NTN can provide the next cell information along the satellite trajectory using System Information Broadcast (SIB). The assistance information can include satellite's long term ephemeris in the format of Position Velocity (PV) information or details of satellite's other orbital parameters. During TN-NTN join coverage, as TN cells are expected to have a better coverage then NTN cells, the network can assign higher priority to the TN cells over NTN cells. Similarly, for a mobility involving earth-fixed and earth-moving beams (cells), earth-fixed cells can be prioritized over earth-moving beams for cell reselection.

Methods for a New Radio (NR)-based, Low Earth Orbit (LEO) Non-Terrestrial Networks (NTN) are proposed to improve cell selection and reselection by using satellite assistance information. Different from traditional 5G New Radio systems, the LEO NTN can provide the next cell information along the satellite trajectory using System Information Broadcast (SIB). The assistance information can include satellite's long term ephemeris in the format of Position Velocity (PV) information or details of satellite's other orbital parameters. During TN-NTN join coverage, as TN cells are expected to have a better coverage then NTN cells, the network can assign higher priority to the TN cells over NTN cells. Similarly, for a mobility involving earth-fixed and earth-moving beams (cells), earth-fixed cells can be prioritized over earth-moving beams for cell reselection.

The present invention relates to satellite systems and more particularly, to the provision of a satellite system and method for communications applications, with global coverage. An optimal method of providing global broadband connectivity has been discovered which uses two different LEO constellations with inter-satellite links among the satellites in each constellation, and inter-satellite links between the constellations. The first constellation is deployed in a polar LEO orbit with a preferred inclination of 99.5 degrees and a preferred altitude of 1000 km. The second constellation is deployed in an inclined LEO orbit with a preferred inclination of 37.4 degrees and a preferred altitude of 1250 km.

The present invention relates to satellite systems and more particularly, to the provision of a satellite system and method for communications applications, with global coverage. An optimal method of providing global broadband connectivity has been discovered which uses two different LEO constellations with inter-satellite links among the satellites in each constellation, and inter-satellite links between the constellations. The first constellation is deployed in a polar LEO orbit with a preferred inclination of 99.5 degrees and a preferred altitude of 1000 km. The second constellation is deployed in an inclined LEO orbit with a preferred inclination of 37.4 degrees and a preferred altitude of 1250 km.

An indication method and an indication device are provided. The method includes obtaining satellite parameters of a current satellite cell and one or more neighbor satellite cells, wherein the current satellite cell is a satellite cell where a terminal is located, the one or more neighbor satellite cells are satellite cells neighboring the current satellite cell; determining a basic list and a detailed list according to the satellite parameters of the current satellite cell and the neighbor satellite cells, wherein the basic list includes basic information of the neighbor satellites, and the detailed list includes detailed information of the neighbor satellites; sending the basic list and/or the detailed list to the terminal.

A device for the reception of ADS-B messages for a satellite is disclosed including an array of sources and a beamforming module, a ground footprint of a field of view defining a service area, different service areas being associated with different positions of the satellite, a ground footprint of a beam defining a spot in the service area, the beamforming module being configured to form each beam by applying combination coefficients, the reception device having a processing circuit configured to obtain information representative of a position of the satellite and to modify a set of combination coefficients so as to adapt the surface area and/or or the shape of the formed spots to a geographical distribution of the aircrafts within the service area associated with the position of the satellite.

A device for the reception of ADS-B messages for a satellite is disclosed including an array of sources and a beamforming module, a ground footprint of a field of view defining a service area, different service areas being associated with different positions of the satellite, a ground footprint of a beam defining a spot in the service area, the beamforming module being configured to form each beam by applying combination coefficients, the reception device having a processing circuit configured to obtain information representative of a position of the satellite and to modify a set of combination coefficients so as to adapt the surface area and/or or the shape of the formed spots to a geographical distribution of the aircrafts within the service area associated with the position of the satellite.