Disclosed are methods and apparatuses for transmitting and receiving characteristic information of a GNSS subframe. A method for transmitting and receiving characteristic information of a GNSS subframe, as a method for a first device, may comprise: receiving a subframe including first information, which is characteristic information of the subframe, from a second device; checking a format of the subframe on the basis of the first information; and determining whether to decode data included in the subframe on the basis of the checked format of the subframe.

Signal, data transmission, and/or encryption units generating a cryptographic code using a cryptographic key before writing to a pseudorandom noise buffer memory. The PRN code generator comprises a first processor generating a PRN code from initial data using a cryptographic key. A second processor generates sections of the PRN code for integrity check purposes through computation using the same cryptographic key and initial data. Within the PRN code generator and before temporary storage of the PRN code in the buffer memory, there is a comparison device for comparing at least one duplicated section of the PRN code sequence cryptographically generated by the first processor with the section computed by the second processor. A blocking, stop and/or alarm function is activated in the comparison device and triggered on the basis of a predefined degree of matching between the section obtained through duplication and the computed section.

Coordinated smart contract-based satellite management and operation is provided by obtaining terms of smart contracts that govern utilization of a constellation of Earth-orbiting satellites, which form a space-based data center, in transmitting data between the constellation of satellites and ground stations for receiving data transmissions. Different service providers operate different satellites of the constellation and different ground stations of the collection, and the smart contracts further govern servicing of requests made between the different service providers. A service provider operates satellite(s) of the constellation pursuant to the smart contracts and ground station(s) of the collection of ground stations. This includes receiving a request for data stored on a satellite, selecting a device to which the satellite is to send the data, the selecting being made between at least (i) a ground station and (ii) another satellite of the constellation, and initiating sending the data to the selected device.

Coordinated smart contract-based satellite management and operation is provided by obtaining terms of smart contracts that govern utilization of a constellation of Earth-orbiting satellites, which form a space-based data center, in transmitting data between the constellation of satellites and ground stations for receiving data transmissions. Different service providers operate different satellites of the constellation and different ground stations of the collection, and the smart contracts further govern servicing of requests made between the different service providers. A service provider operates satellite(s) of the constellation pursuant to the smart contracts and ground station(s) of the collection of ground stations. This includes receiving a request for data stored on a satellite, selecting a device to which the satellite is to send the data, the selecting being made between at least (i) a ground station and (ii) another satellite of the constellation, and initiating sending the data to the selected device.

A low-earth orbit (LEO) satellite includes a global positioning receiver configured to receive first signaling from a first plurality of non-LEO navigation satellites. An inter-satellite transceiver is configured to send and receive inter-satellite communications with other LEO navigation satellites. At least one processor is configured to execute operational instructions that cause the at least one processor to perform operations that include: determining an orbital position of the LEO satellite based on the first signaling; and generating a navigation message based on the orbital position. A navigation signal transmitter configured to broadcast the navigation message to at least one client device, the navigation message facilitating the at least one client device to determine an enhanced position of the at least one client device based on the navigation message and further based on second signaling received from a second plurality of non-LEO navigation satellites.

A low-earth orbit (LEO) satellite includes a global positioning receiver configured to receive first signaling from a first plurality of non-LEO navigation satellites. An inter-satellite transceiver is configured to send and receive inter-satellite communications with other LEO navigation satellites. At least one processor is configured to execute operational instructions that cause the at least one processor to perform operations that include: determining an orbital position of the LEO satellite based on the first signaling; and generating a navigation message based on the orbital position. A navigation signal transmitter configured to broadcast the navigation message to at least one client device, the navigation message facilitating the at least one client device to determine an enhanced position of the at least one client device based on the navigation message and further based on second signaling received from a second plurality of non-LEO navigation satellites.

A low-earth orbit (LEO) satellite includes a global positioning receiver configured to receive first signaling from a first plurality of non-LEO navigation satellites of a constellation of non-LEO navigation satellites in non-LEO around the earth. An inter-satellite transceiver is configured to send and receive inter-satellite communications with other LEO navigation satellites in a constellation of LEO navigation satellites. At least one processor is configured to execute operational instructions that cause the at least one processor to perform operations that include: determining an orbital position of the LEO satellite based on applying precise point positioning (PPP) correction data to the first signaling, wherein the PPP correction data is received separately from the first signaling; and generating a navigation message based on the orbital position. A navigation signal transmitter is configured to broadcast the navigation message to at least one client device, the navigation message facilitating the at least one client device to determine an enhanced position of the at least one client device based on the navigation message.

A low-earth orbit (LEO) satellite includes a global positioning receiver configured to receive first signaling from a first plurality of non-LEO navigation satellites of a constellation of non-LEO navigation satellites in non-LEO around the earth. An inter-satellite transceiver is configured to send and receive inter-satellite communications with other LEO navigation satellites in a constellation of LEO navigation satellites. At least one processor is configured to execute operational instructions that cause the at least one processor to perform operations that include: determining an orbital position of the LEO satellite based on applying precise point positioning (PPP) correction data to the first signaling, wherein the PPP correction data is received separately from the first signaling; and generating a navigation message based on the orbital position. A navigation signal transmitter is configured to broadcast the navigation message to at least one client device, the navigation message facilitating the at least one client device to determine an enhanced position of the at least one client device based on the navigation message.

A locating and communication method for a radio terminal by means of a satellite locating and communication system, which implements a first step, in the course of which the radio terminal transmits to a non-geostationary satellite a repeating sequence a predetermined number of times N for the same data packet, which is time-shifted by the same predetermined time shift Δτ each time is provided. Subsequently, a satellite access and processing ground station determines the location of the radio terminal from the data packets with access, which are extracted from a listening signal digitized and dated by the satellite and from the same detected sequence associated with said radio terminal, and from the ephemerides of the satellite by using a technique for measuring angle or angles of arrival by means of sequenced interferometry associated with a technique for measuring Doppler drift or drifts.

A locating and communication method for a radio terminal by means of a satellite locating and communication system, which implements a first step, in the course of which the radio terminal transmits to a non-geostationary satellite a repeating sequence a predetermined number of times N for the same data packet, which is time-shifted by the same predetermined time shift Δτ each time is provided. Subsequently, a satellite access and processing ground station determines the location of the radio terminal from the data packets with access, which are extracted from a listening signal digitized and dated by the satellite and from the same detected sequence associated with said radio terminal, and from the ephemerides of the satellite by using a technique for measuring angle or angles of arrival by means of sequenced interferometry associated with a technique for measuring Doppler drift or drifts.