A high-throughput satellite access method and system based on 5G NR

Abstract

The application discloses a high-throughput satellite access method and system based on 5G NR. The method is as follows: a beacon signal and a random access channel are arranged on a global signaling beam of a high-throughput satellite; a satellite terminal requests a service beam service of the high-throughput satellite through the random access channel; all satellite terminals share the random access channel, and resource competition is realized through a random backoff competition mechanism; the satellite terminal adjusts an antenna pointing direction and reports user position information by using the global signaling beam; a satellite system adjusts a variable service beam pointing direction according to the user position information, and provides access service for the user; the satellite system provides a 5G broadcast signal for the user through the service beam, and completes broadcast reception and random access of the 5G satellite system. The system realizes the high-throughput satellite access method based on 5G NR. The application realizes satellite terminal access based on 5G standards without affecting an existing synchronous orbit high-throughput satellite architecture.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of high-throughput satellite communication and 5G NR access technology, and particularly relates to a high-throughput satellite access method and system based on 5G NR. BACKGROUND

[0002] A high-throughput satellite communication system is a broadband satellite communication system for signal forwarding through multiple high-orbit satellites. Currently, the high-throughput satellite communication systems under construction or already completed in the world mainly include the maritime satellite, Intesat, etc., and the systems in China mainly include the Zhongxing-16, etc. Figure 1 As shown in the following figure:

[0003] Generally, in order to provide user service rates, the high-throughput satellite user side usually carries two types of phased array antennas and parabolic antennas, the former forms a narrow point beam to provide high-speed service transmission services for user terminals, which is a service beam, and the latter forms a global signaling beam to guide user terminals to access, which is a signaling beam, as shown in the following figure: Figure 2 The global beam is relatively fixed with respect to the satellite, but the narrow point beam can adjust the pointing direction of the beam according to user needs.

[0004] The ground segment, as an important component of the high-throughput satellite communication system, completes the management of satellite payloads and the functions of service processing, network management, operation management, cross-border business settlement, etc. of the high-throughput satellite communication system, and is responsible for the interconnection of the high-throughput satellite communication system and other systems, mainly composed of a running control center, a global operation service center and gateway stations distributed all over the world. The gateway station system provides signaling beam and service beam signal processing functions for the high-throughput satellite communication system.

[0005] In order to reduce the system development cost and research and development risk, make full use of the existing research and development results of ground mobile communication, and maximize the inheritance of the low-cost and industrialized mobile industry system, it has become a future research direction to transplant the ground 5G mobile communication system into the high-throughput satellite communication system. However, in the synchronous orbit high-throughput satellite system, the global broadcast signaling beam transmission capacity is weak and cannot bear the 5G broadcast signal-based and subsequent signaling access. SUMMARY

[0006] The purpose of the present application is to provide a high-throughput satellite access method and system based on 5G NR, which realizes satellite terminal access based on 5G standards without affecting the existing synchronous orbit high-throughput satellite architecture.

[0007] The technical solution for achieving the purpose of the present application is: a high-throughput satellite access method based on 5G NR, specifically comprising:

[0008] A beacon signal and a random access channel are arranged on the global signaling beam of the high-throughput satellite.

[0009] The satellite terminal requests service beam service from the high-throughput satellite through a random access channel, all satellite terminals share the random access channel, and resource competition is realized through a random backoff competition mechanism;

[0010] The satellite terminal adjusts the antenna pointing and reports the user position information using a global signaling beam, and the satellite system adjusts the variable service beam pointing according to the user position information to provide access services for the user;

[0011] The satellite system provides 5G broadcast signals to the user through the service beam, and completes the broadcast reception and random access of the 5G satellite system.

[0012] Further, the beacon signal is a single-carrier continuous spread spectrum signal, which transmits public information such as synchronization signals, satellite identification, and ephemeris information, and the satellite terminal uses the beacon signal for initial timing synchronization of the system and identifies whether the access satellite is a service satellite.

[0013] Further, the beacon signal is generated by a gateway station and broadcast to all users through a transparent transponder of the satellite via a feeder link.

[0014] Further, the satellite terminal random access process is as follows:

[0015] (1.1) After the satellite terminal requests service beam service from the high-throughput satellite system through the random access channel, it immediately enters the search phase of the 5G broadcast signal and starts the random backoff timer;

[0016] (1.2) When the 5G broadcast signal is searched, the satellite terminal immediately stops the random access process and the backoff timer, and starts 5G network access;

[0017] (1.3) When the backoff timer times out, the satellite terminal initiates an access request to the high-throughput satellite system again and enters the 5G broadcast signal search phase, and starts the random backoff timer again;

[0018] (1.4) Until the terminal accesses the satellite 5G network.

[0019] Further, when the satellite terminal needs to access, the high-throughput satellite terminal location is notified through the random access channel, and the high-throughput satellite network system adjusts the variable service beam to the user position to realize user access, and the specific process is as follows:

[0020] (2.1) The high-throughput satellite system broadcasts a global beacon signal and waits for the satellite terminal to access;

[0021] (2.2) The high-throughput satellite system continuously monitors the random access channel according to a fixed receiving window, identifies the user identity after capturing the user random access signal, and if it is a legal user, adjusts the satellite terminal position information to the user's location, and if the terminal user is not a network valid user, discards the corresponding random access message;

[0022] (2.3) In the service beam, the high-throughput satellite system broadcasts the 5G-based broadcast message to the user, which includes the synchronization signal, the satellite real-time ephemeris information, the system configuration information, the paging message, and the SIB1 message synthesized by the phased array service beam broadcast to the user;

[0023] (2.4) The satellite terminal demodulates and decodes the system broadcast message, and calculates the relative distance and speed between the terminal and the satellite according to the satellite real-time ephemeris, the local time, and the terminal position information, estimates the Doppler frequency offset and the satellite-ground round-trip time delay according to the frequency of the PRACH channel, and pre-compensates the transmission timing and frequency offset of the PRACH channel, and sends MSG-1 to the high-throughput satellite system through the PRACH channel in the phased array service beam;

[0024] (2.5) The high-throughput satellite system measures the PRACH channel to obtain the uplink frequency offset and time offset of the satellite terminal, and allocates channel resources to the satellite terminal according to the user resource demand to form the RAR message and send it to the satellite terminal through the PDCCH channel;

[0025] (2.6) The satellite terminal waits for the RAR message and tries to detect the PDCCH in the RAR window using the corresponding RA-RNTI, and if the PDCCH is detected, the uplink timing advance and frequency adjustment parameters defined in the RAR message are obtained, as well as the uplink scheduling resource information;

[0026] (2.7) The satellite terminal sends MSG3 to the high-throughput satellite system, and the MSG3 transmits the RRC establishment request message. The terminal realizes the uplink synchronization between the satellite terminal and the gateway system according to the uplink timing advance and frequency adjustment parameters in the RAR message, and sends MSG3 on the PUSCH channel according to the uplink scheduling resource information;

[0027] (2.8) The high-throughput satellite system sends MSG4 to the satellite terminal, and after receiving and analyzing the satellite terminal identifier contained in MSG3, the high-throughput satellite system sends MSG4 on the PDSCH channel. The satellite terminal receives and decodes the contention resolution message contained in MSG4 on the PDSCH channel, and thus completes the random access process.

[0028] Further, the high-throughput satellite system broadcasts a global beacon signal in step (2.1) to wait for the satellite terminal to access, which specifically includes:

[0029] The satellite terminal calculates the azimuth and elevation angles of the satellite according to the ephemeris data in the storage device, the local time, and the terminal position, adjusts the azimuth and elevation angles according to the planned scanning path, scans the beacon signal, and searches for the relative maximum value of the satellite beacon signal;

[0030] When the relative maximum value of the satellite beacon is searched, the satellite terminal beam is adjusted to accurately point and begin to parse the beacon signal, update the stored ephemeris data, and judge whether the current satellite is a service satellite. If the current satellite is a service satellite, a random access process is initiated;

[0031] In the random access process, the satellite terminal calculates the relative distance and speed between the satellite terminal and the satellite according to the real-time ephemeris of the satellite, the local time, and the terminal position, estimates the Doppler frequency offset and the satellite-ground round-trip delay according to the frequency of the random access channel, pre-compensates the transmission timing and frequency deviation of the random access channel, and sends random access signaling to the high-throughput satellite. The random access signaling includes the user's identity information and terminal position information.

[0032] A high-throughput satellite access system based on 5G NR, which realizes any of the high-throughput satellite access methods based on 5G NR.

[0033] Further, the system comprises:

[0034] A setting module for setting a beacon signal and a random access channel on a global signaling beam of a high-throughput satellite;

[0035] A service beam service request module for a satellite terminal to request a service beam service from a high-throughput satellite through a random access channel. All satellite terminals share the random access channel, and resource competition is realized through a random backoff competition mechanism.

[0036] A variable service beam pointing adjustment module, which has the functions of: a satellite terminal uses a global signaling beam to complete antenna pointing adjustment and user position information reporting, and a satellite system adjusts the pointing of a variable service beam according to the user position information to provide access services for users.

[0037] A 5G broadcast receiving and access module, which has the functions of: a satellite system provides a 5G broadcast signal to users through a service beam to complete the broadcast receiving and random access of a 5G satellite system.

[0038] Compared with the prior art, the present application has the following advantages: (1) the satellite terminal uses the global signaling beam to complete the antenna pointing adjustment and user position information reporting, and the satellite system adjusts the variable service beam pointing according to the user position information to provide access services for the user; (2) the satellite system provides the 5G broadcast signal to the user through the service beam to complete the broadcast reception and random access of the 5G satellite system, and the subsequent process switching is completed through the service beam; (3) based on the existing geosynchronous orbit high-throughput satellite architecture, the satellite terminal access based on the 5G standard is realized, and the problems of weak global signaling beam transmission capacity of the high-throughput satellite system and the inability to carry the 5G broadcast signal and subsequent signaling access are solved. BRIEF DESCRIPTION OF DRAWINGS

[0039] Figure 1 is a schematic diagram of a high-throughput satellite communication system.

[0040] Figure 2 is a schematic diagram of a satellite carrying a processing and transparent forwarding payload.

[0041] Figure 3 is a schematic diagram of a beacon signal carried in a global signaling beam.

[0042] Figure 4 is a schematic diagram of an access signal carried in a global signaling beam.

[0043] Figure 5 is a satellite terminal random access flowchart.

[0044] Figure 6 is a terminal access process schematic diagram. DETAILED DESCRIPTION

[0045] The present application is a high-throughput satellite access method based on 5G NR, which specifically includes:

[0046] A beacon signal and a random access channel are arranged on the global signaling beam of the high-throughput satellite.

[0047] The satellite terminal requests the service beam service of the high-throughput satellite through the random access channel, all satellite terminals share the random access channel, and the resource competition is realized through the random backoff competition mechanism.

[0048] The satellite terminal uses the global signaling beam to complete the antenna pointing adjustment and user position information reporting, and the satellite system adjusts the variable service beam pointing according to the user position information to provide access services for the user.

[0049] The satellite system provides the 5G broadcast signal to the user through the service beam to complete the broadcast reception and random access of the 5G satellite system.

[0050] Further, the beacon signal is a single-carrier continuous spread spectrum signal, which transmits public information such as synchronization signal, satellite identification, ephemeris information, and the satellite terminal uses the beacon signal for initial timing synchronization of the system, and identifies whether the accessed satellite is a service satellite.

[0051] Further, the beacon signal is generated by the gateway station and broadcast to all users through the transparent transponder of the satellite via the feeder link.

[0052] Further, the random access process of the satellite terminal is as follows:

[0053] (1.1) After the satellite terminal requests service beam service from the high-throughput satellite system through the random access channel, it immediately enters the search phase of the 5G broadcast signal and starts the random backoff timer;

[0054] (1.2) When the 5G broadcast signal is searched, the satellite terminal immediately stops the random access process and the backoff timer, and starts 5G network access;

[0055] (1.3) When the backoff timer expires, the satellite terminal initiates an access request to the high-throughput satellite system again, and enters the 5G broadcast signal search phase, and starts the random backoff timer again;

[0056] (1.4) Until the terminal accesses the satellite 5G network.

[0057] Further, when the satellite terminal needs to access, it notifies the high-throughput satellite terminal location through the random access channel, and the high-throughput satellite network system adjusts the variable service beam to the user location to realize user access, and the specific process is as follows:

[0058] (2.1) The high-throughput satellite system broadcasts global beacon signals and waits for satellite terminal access;

[0059] (2.2) The high-throughput satellite system continuously monitors the random access channel according to the fixed receiving window, and when the user random access signal is captured, the user identity is identified, if it is a legal user, the satellite terminal position information is adjusted according to the satellite terminal position information, and the user is located in the position of the user; If the terminal user is not a network valid user, the corresponding random access message is discarded;

[0060] (2.3) In the service beam, the high-throughput satellite system broadcasts the 5G-based broadcast message to the user, which includes synchronization signal, satellite real-time ephemeris information, system configuration information, paging message, and synthesizes SIB1 message through phased array service beam broadcast to the user;

[0061] (2.4) The satellite terminal demodulates and decodes the system broadcast message, and calculates the relative distance and speed between the terminal and the satellite according to the satellite real-time ephemeris, local time, terminal position, etc. The Doppler frequency offset and the satellite-ground round-trip delay are estimated according to the frequency of the PRACH channel, and the transmission timing and frequency offset of the PRACH channel are pre-compensated. MSG-1 is sent to the high-throughput satellite system through the PRACH channel on the phased array service beam;

[0062] (2.5) The high-throughput satellite system measures the PRACH channel to obtain the uplink frequency offset and time offset of the satellite terminal, and allocates channel resources to the satellite terminal according to the user resource demand to form a RAR message and send it to the satellite terminal through the PDCCH channel;

[0063] (2.6) The satellite terminal waits for the RAR message and attempts to detect the PDCCH in the RAR window using the corresponding RA-RNTI. If the PDCCH of the satellite terminal is detected, the uplink timing advance and frequency adjustment parameters defined in the RAR message, as well as the uplink scheduling resource information, are obtained;

[0064] (2.7) The satellite terminal sends MSG3 to the high-throughput satellite system. MSG3 transmits the RRC establishment request message. The terminal realizes uplink synchronization with the gateway system according to the uplink timing advance and frequency adjustment parameters in the RAR message, and sends MSG3 on the PUSCH channel according to the uplink scheduling resource information;

[0065] (2.8) The high-throughput satellite system sends MSG4 to the satellite terminal. After receiving and analyzing the satellite terminal identifier contained in MSG3, the high-throughput satellite system sends MSG4 on the PDSCH channel. The satellite terminal receives and decodes the contention resolution message contained in MSG4 on the PDSCH channel. Thus, the terminal completes the random access process.

[0066] Further, the high-throughput satellite system broadcasts a global beacon signal in step (2.1) to wait for satellite terminal access, which specifically includes:

[0067] The satellite terminal calculates the azimuth and elevation angles of the satellite according to the ephemeris data, local time, and terminal position in the storage device, adjusts the azimuth and elevation angles according to the planned scanning path, scans the beacon signal, and searches for the relative maximum value of the satellite beacon signal;

[0068] When the relative maximum value of the satellite beacon is searched, the satellite terminal beam is adjusted to accurately point and begin to analyze the beacon signal, update the stored ephemeris data, and determine whether the current satellite is a service satellite. If the current satellite is a service satellite, the random access process is initiated;

[0069] In the random access process, the satellite terminal calculates the relative distance and speed between the satellite terminal and the satellite according to the satellite real-time ephemeris, local time, terminal position information, estimates the Doppler frequency offset and the satellite-ground round-trip delay according to the frequency of the random access channel, pre-compensates the transmission timing and frequency offset of the random access channel, and sends the random access signaling to the high-throughput satellite. The random access signaling includes the identity information of the user and the terminal position information.

[0070] A high-throughput satellite access system based on 5G NR, which realizes any one of the high-throughput satellite access methods based on 5G NR.

[0071] Further, the system comprises:

[0072] The setting module is configured to set a beacon signal and a random access channel on a global signaling beam of the high-throughput satellite.

[0073] The service beam service request module is configured to request a service beam service from the high-throughput satellite by the satellite terminal through the random access channel. All satellite terminals share the random access channel, and resource competition is realized through a random backoff competition mechanism.

[0074] The variable service beam pointing adjustment module is configured to: the satellite terminal adjusts the antenna pointing and reports the user position information by using the global signaling beam, and the satellite system adjusts the variable service beam pointing according to the user position information to provide access service for the user.

[0075] The 5G broadcast receiving and access module is configured to: the satellite system provides a 5G broadcast signal to the user through the service beam to complete the broadcast receiving and random access of the 5G satellite system.

[0076] The application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0077] Embodiment

[0078] The high-throughput satellite access method and system based on 5G NR in the embodiment are configured to: the satellite terminal adjusts the antenna pointing and reports the user position information by using the global signaling beam, and the satellite system adjusts the variable service beam pointing according to the user position information to provide access service for the user. The satellite system provides a 5G broadcast signal to the user through the service beam to complete the broadcast receiving and random access of the 5G satellite system, and the subsequent process is switched to the service beam.

[0079] The application will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0080] 1. Global signaling beam access design

[0081] The beacon signal and the random access channel are set on the global signaling beam of the traditional high-throughput satellite, for example, Figure 3shown.

[0082] In high-throughput satellite systems, due to the high operating frequency band, large satellite terminal antenna aperture, and narrow user beam width, in order to ensure that the terminal accurately points to the satellite, the signal is designed as a single-carrier continuous spread spectrum signal, transmitting a small amount of public information such as synchronization signals, satellite identification, ephemeris information and other data content. The satellite terminal can use a single-pulse closed-loop tracking mechanism to improve the antenna pointing accuracy, and can also use the beacon signal to perform preliminary system timing synchronization to identify whether the access satellite is a service satellite. In order to achieve initial synchronization from the satellite terminal to the network, the beacon signal is generated by the gateway and broadcast to all users through the feeder link via the satellite transparent repeater. The access signal carried in the global signaling beam is such as Figure 4 shown.

[0083] Satellite terminals request service beams from high-throughput satellites through random access channels. Random access channels are burst signals with short time intervals. All satellite terminals share the random access channel and implement resource competition through a random backoff competition mechanism. The access process is as follows: Figure 5 As shown, the details are as follows:

[0084] (1) After the satellite terminal requests the service beam service from the high-throughput satellite system through the random access channel, it immediately enters the search phase for the 5G broadcast signal and starts the random backoff timer;

[0085] (2) When the 5G broadcast signal is found, the satellite terminal immediately stops the random access process and backoff timer and starts 5G network access;

[0086] (3) When the backoff timer times out, the satellite terminal initiates an access request to the high-throughput satellite system again, enters the 5G broadcast signal search phase, and starts the random backoff timer again;

[0087] (4) Until the terminal is connected to the satellite 5G network.

[0088] 2. Satellite terminal 5G access process

[0089] Beacon signals and random access channels are configured on the global signaling beam of the high-throughput satellite. When a satellite terminal needs access, the location of the high-throughput satellite terminal is notified through the access channel. The high-throughput satellite network system adjusts the variable service beam to the user's location to achieve user access. Figure 6 The specific process is as follows:

[0090] (1) The high-throughput satellite system broadcasts a global beacon signal and waits for satellite terminals to access it.

[0091] The satellite terminal calculates the azimuth and elevation angles of the satellite according to the non-precise ephemeris data in the non-volatile storage device, local time, terminal position and the like, adjusts the azimuth and elevation angles according to the planned scanning path, quickly scans the beacon signal, and searches for the relative maximum value of the satellite beacon signal.

[0092] When the relative maximum value of the satellite beacon is searched, the satellite terminal beam is adjusted to accurately point and begin to parse the beacon signal, update the stored ephemeris data, and judge whether the current satellite is a service satellite. If the current satellite is a service satellite, a random access process is initiated.

[0093] In the random access process, the satellite terminal calculates the relative distance and speed between the satellite terminal and the satellite according to the real-time ephemeris of the satellite, local time, terminal position and the like, estimates the Doppler frequency offset and satellite-ground round-trip delay according to the frequency of the random access channel, pre-compensates the transmission timing and frequency offset of the random access channel, and sends random access signaling to the high-throughput satellite. The random access signaling includes user identity information, terminal position information and the like.

[0094] (2) The high-throughput satellite system continuously listens to the random access channel according to the fixed receiving window, identifies the user identity when the user random access signal is captured, and adjusts the satellite-borne phased array service beam to point to the user's location according to the terminal position information if the user is a legal user. If the terminal user is not a valid network user, the corresponding random access message is discarded.

[0095] (3) In the service beam, the high-throughput satellite system broadcasts 5G-based broadcast messages to users, which include synchronization signals, real-time satellite ephemeris information, system other configuration information (such as PRACH channel configuration and parameters), paging messages, etc., and are synthesized into SIB1 messages and broadcast to users through the phased array service beam.

[0096] (4) The satellite terminal demodulates and decodes the system broadcast message, calculates the relative distance and speed between the terminal and the satellite according to the real-time ephemeris of the satellite, local time, terminal position and the like, estimates the Doppler frequency offset and satellite-ground round-trip delay according to the frequency of the PRACH channel, pre-compensates the transmission timing and frequency offset of the PRACH channel, and sends MSG-1 to the high-throughput satellite system through the PRACH channel on the phased array service beam.

[0097] (5) The high-throughput satellite system measures the PRACH channel to obtain the uplink frequency offset and time offset of the satellite terminal, and allocates channel resources to the satellite terminal according to the user resource demand to form a RAR message and send it to the satellite terminal through the PDCCH channel.

[0098] (6) The satellite terminal waits for the RAR message, attempts to detect the PDCCH (DCI) using the corresponding RA-RNTI within the time period of the RAR window, if the PDCCH of itself is detected, the uplink timing advance and frequency adjustment parameters and uplink scheduling resource information defined in the RAR message are obtained.

[0099] (7) The satellite terminal sends the MSG3 (RRC Setup Request message) to the high-throughput satellite system, the terminal realizes the accurate uplink synchronization between the terminal and the gateway station system according to the uplink timing advance and frequency adjustment parameters in the RAR message, and sends the MSG3 on the PUSCH channel according to the uplink scheduling resource information.

[0100] (8) The high-throughput satellite system sends the MSG4 (Contention Resolution) to the satellite terminal, after receiving and analyzing the satellite terminal identifier contained in the MSG3, the high-throughput satellite system sends the MSG4 on the PDSCH channel, the satellite terminal receives and decodes the contention resolution message contained in the MSG4 on the PDSCH channel, and thus the four-step random access process of the terminal is completed.

[0101] The application realizes the satellite terminal access process based on the 5G standard without affecting the existing geosynchronous orbit high-throughput satellite architecture, solves the problem that the global signaling beam transmission capacity of the high-throughput satellite system is weak and cannot carry the 5G broadcast signal and subsequent signaling access based on the 5G broadcast signal.

Claims

1. A high-throughput satellite access method based on 5G NR, characterized in that: Specifically include: Setting up beacon signals and random access channels on the global signaling beam of the high-throughput satellite; Satellite terminals request service beams from high-throughput satellites through random access channels. All satellite terminals share the random access channels and implement resource competition through a random backoff contention mechanism. Satellite terminals use global signaling beams to adjust antenna pointing and report user location information. The satellite system adjusts the direction of variable service beams based on user location information to provide access services to users. The satellite system provides 5G broadcast signals to users through service beams, completing broadcast reception and random access of the 5G satellite system; The beacon signal is a single-carrier continuous spread spectrum signal that transmits public information such as synchronization signal, satellite identification, and ephemeris information. The satellite terminal uses the beacon signal to perform initial system timing synchronization and identify whether the access satellite is a service satellite. The beacon signal is generated by the gateway and broadcast to all users via the feeder link via the satellite transparent repeater; The satellite terminal random access process is as follows: (1.1) After the satellite terminal requests the service beam service from the high-throughput satellite system through the random access channel, it immediately enters the search phase for the 5G broadcast signal and starts the random backoff timer; (1.2) When the 5G broadcast signal is found, the satellite terminal immediately stops the random access process and backoff timer and starts 5G network access; (1.3) When the backoff timer expires, the satellite terminal initiates an access request to the high-throughput satellite system again, enters the 5G broadcast signal search phase, and starts the random backoff timer again; (1.4) Until the terminal is connected to the satellite 5G network; When a satellite terminal needs access, the location of the high-throughput satellite terminal is notified through the random access channel. The high-throughput satellite network system adjusts the variable service beam to the user's location to enable user access. The specific process is as follows: (2.1) The high-throughput satellite system broadcasts a global beacon signal and waits for satellite terminals to access it; (2.2) The high-throughput satellite system continuously monitors the random access channel according to a fixed receiving window. When a user's random access signal is captured, the system identifies the user. If the user is a legitimate user, the system adjusts the onboard phased array service beam to point to the user's location based on the satellite terminal's location information. If the terminal user is not a valid network user, the system discards the corresponding random access message. (2.3) In the service beam, the high-throughput satellite system broadcasts 5G-based broadcast messages to users. These broadcast messages include synchronization signals, satellite real-time ephemeris information, system configuration information, paging messages, and synthesized SIB1 messages, which are broadcast to users via the phased array service beam. (2.4) The satellite terminal demodulates and decodes the system broadcast message, and calculates the relative distance and velocity between the terminal and the satellite based on the satellite's real-time ephemeris, local time, and terminal position. It estimates the Doppler frequency offset and satellite-to-ground round-trip delay based on the PRACH channel frequency, pre-compensates the PRACH channel's transmit timing and frequency deviation, and sends the MSG-1 to the high-throughput satellite system via the PRACH channel on the phased array service beam. (2.5) The high-throughput satellite system measures the PRACH channel to obtain the satellite terminal's uplink frequency offset and time offset. It also allocates channel resources to the satellite terminal based on user resource requirements, generates a RAR message, and sends it to the satellite terminal via the PDCCH channel. (2.6) The satellite terminal waits for the RAR message and attempts to detect the PDCCH using the corresponding RA-RNTI within the RAR window. If its own PDCCH is detected, it obtains the uplink timing advance and frequency adjustment parameters defined in the RAR message, as well as the uplink scheduling resource information; (2.7) The satellite terminal sends MSG3 to the high-throughput satellite system. MSG3 carries the RRC establishment request message. The terminal achieves uplink synchronization with the gateway system based on the uplink timing advance and frequency adjustment parameters in the RAR message, and sends MSG3 on the PUSCH channel based on the uplink scheduling resource information. (2.8) The high-throughput satellite system sends MSG4 to the satellite terminal. After receiving and parsing the satellite terminal identifier contained in MSG3, the high-throughput satellite system sends MSG4 on the PDSCH channel. The satellite terminal receives and decodes the contention resolution message contained in MSG4 on the PDSCH channel. At this point, the terminal completes the random access process. The high-throughput satellite system described in step (2.1) broadcasts a global beacon signal and waits for satellite terminals to access it, specifically including: The satellite terminal calculates the azimuth and elevation angles of the satellite based on the ephemeris data, local time, and terminal location stored in the storage device. It then adjusts the azimuth and elevation angles according to the planned scanning path, scans for beacon signals, and searches for the relative maximum value of the satellite beacon signal. When the relative maximum value of the satellite beacon is found, the satellite terminal beam is adjusted to accurately point and the beacon signal is analyzed. The stored ephemeris data is updated and it is determined whether the current satellite is a service satellite. If the current satellite is a service satellite, a random access process is initiated. During the random access process, the satellite terminal calculates the relative distance and speed between the satellite terminal and the satellite based on the satellite's real-time ephemeris, local time, and terminal location information, estimates the Doppler frequency offset and the satellite-to-ground round-trip delay based on the frequency of the random access channel, pre-compensates the transmission timing and frequency deviation of the random access channel, and sends random access signaling to the high-throughput satellite. The random access signaling includes the user's identity information and terminal location information.

2. A high-throughput satellite access system based on 5G NR, characterized in that: The system implements the high-throughput satellite access method based on 5G NR described in claim 1.

3. The 5G NR-based high-throughput satellite access system according to claim 2, wherein: The system includes: A setting module, used for setting a beacon signal and a random access channel on a global signaling beam of a high-throughput satellite; The service beam service request module is used by satellite terminals to request service beam services from high-throughput satellites through random access channels. All satellite terminals share the random access channel and implement resource competition through a random backoff competition mechanism. The variable service beam pointing adjustment module has the following functions: the satellite terminal uses the global signaling beam to complete antenna pointing adjustment and report user location information. The satellite system adjusts the variable service beam pointing based on the user location information to provide access services to users. The 5G broadcast reception and access module has the following functions: the satellite system provides 5G broadcast signals to users through service beams, and completes the broadcast reception and random access of the 5G satellite system.

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