Method and system for adaptively accessing low-orbit satellite terminal to 5G network

Abstract

The invention provides a method for adaptively accessing a low-orbit satellite terminal to a 5G network, and the method comprises the steps: carrying out the intensity and quality detection of a reference signal of a ground 5G base station through the terminal after the terminal is started, and detecting the intensity and quality of the 5G reference signal in a receiving channel of a satellite link through the terminal. When an available network signal is detected only in the ground direct link, determining to access the 5G network through the ground base station; if available network signals are detected by both the ground direct link and the satellite relay link, the 5G network is still accessed through the ground base station; and when available network signals are detected only in the satellite relay link, accessing the 5G network through the satellite relay link.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of satellite communication, and particularly relates to a method and system for adaptive access of a low-orbit satellite terminal to a 5G network. BACKGROUND

[0002] A 5G communication network is composed of a 5G terminal (UE), a 5G base station (gNodeB), a wireless access network (RAN), a transmission network, and a 5G core network (5GC). The conventional ground network working mode is that the 5G terminal and the 5G ground base station perform wireless signal interaction through a wireless air interface to realize access. Then, the base station accesses the core network through the transmission network to realize the main functions of the 5G network, such as terminal access, mobility management, session management, IP address allocation, user plane path selection, data packet routing and forwarding, policy execution (such as charging and QoS), traffic statistics, and connection to external data networks (Internet and enterprise network).

[0003] Patent CN 113949436 B discloses a high-throughput satellite terminal system that can access a 5G core network. Patent CN 116321506 A discloses a high-throughput satellite access method and system based on 5G NR. Patent CN 118232988 A discloses a satellite terminal inter-satellite network switching simulation method, device, equipment, medium, and product. However, the above patents all study the technical problems of terminal direct connection to satellites, and the research direction is relatively single and clear. They do not consider accessing the 5G core network through the ground 5G base station when there is a 5G network coverage on the ground. Even if there is switching, it is only between different satellites in the same constellation, and does not consider switching access paths. SUMMARY

[0004] The purpose of the present application is to enable the terminal of a low-orbit constellation that uses transparent forwarding technology to realize satellite terminal access to the 5G network to automatically select the optimal path to access the 5G network. When there is a ground network signal, the terminal accesses the 5G network through the ground network base station first, otherwise it accesses the 5G network through the satellite relay. The terminal switches the link rather than just the satellite.

[0005] The technical solution adopted by the present application is as follows:

[0006] The present application provides a system for adaptive access of a low-orbit satellite terminal to a 5G network, which is composed of a satellite terminal, a low-orbit satellite, a ground gateway station, a satellite 5G base station and a ground 5G base station, and a 5G core network. The satellite terminal is a device that continuously provides the best 5G communication service for users. The data generated by the user can be directly transmitted to the terminal or accessed to the Internet through the terminal. The terminal automatically selects whether to access the 5G network through the satellite relay or directly access the 5G network through the ground base station.

[0007] Low-orbit satellites can perform frequency conversion, amplification, and forwarding of satellite 5G downlink signals from ground gateway stations and satellite 5G uplink signals from terminals.

[0008] The ground gateway station will amplify and forward the 5G downlink signal from the satellite 5G base station and the satellite 5G uplink signal from the satellite.

[0009] Satellite 5G base stations are also terrestrial 5G base stations, dedicated to interacting with terrestrial gateway stations to exchange 5G signals. They achieve beam coverage of ground areas by relaying the SSB signals from the 5G base station via satellite frequency conversion. They also respond to uplink signals from terminals originating from the satellite.

[0010] A terrestrial 5G base station is a 5G base station deployed on the ground to enable ordinary 5G user terminals to access the 5G network.

[0011] The 5G core network is the equipment deployed by operators for their standalone 5G networks. Together with terrestrial 5G base stations, it forms the ground-based 5G network coverage.

[0012] The terminal's 5G access adaptive switching function consists of a transmitting satellite antenna module, a receiving satellite antenna module, an up-conversion power amplifier module, a down-conversion amplifier module, a power divider 1 module, a transmit / receive switching switch module, a link switching switch module, a power divider group 2 module, an adaptive switching decision module, a 5G antenna module, and a 5G NR Sub-6 GHz frequency band processing module.

[0013] The satellite antenna module is used to transmit 5G uplink signals to low-Earth orbit satellites, which have been frequency-converted to the uplink frequency of the low-Earth orbit satellites.

[0014] The satellite antenna module is used to receive 5G downlink signals from low-Earth orbit satellites at their downlink frequencies.

[0015] The upconversion power amplifier module is used to convert the standard 5G uplink signal from the 5G NR Sub-6 GHz band processing module to the uplink frequency of low-Earth orbit satellites and amplify the power.

[0016] The downconversion amplifier module is used to convert 5G downlink signals from low-Earth orbit satellites at their downlink frequencies to standard 5G frequencies and amplify them.

[0017] The Power Divider 1 module is used to split the standard 5G signal from the downconversion amplifier module into two paths: one path is sent to the adaptive switching decision module, and the other path is sent to the digest module.

[0018] The transmit / receive switching module is used to switch the standard 5G signal between transmit and receive in TDD mode so that only one signal is connected to the link switching module.

[0019] A 5G antenna module is a device that converts standard 5G signals between electrical signals and radio wave signals.

[0020] The Power Divider Group 2 module splits the standard 5G downlink signal from the 5G antenna module into two paths: one to the adaptive handover decision module and the other to the link handover switch module. Since the 5G antenna module contains multiple antennas, the Power Divider Group 2 module will also have multiple power dividers.

[0021] The adaptive handover decision module is used to calculate the signal strength and signal quality of the standard 5G downlink signal from the satellite and the standard 5G downlink signal from the ground base station, respectively, to obtain network signal evaluations for the two access methods and determine the current access method to be used.

[0022] The link switching module is used to connect the 5G NR Sub-6 GHz band processing module to the signal path of the selected method, either satellite relay access or direct access from a terrestrial base station.

[0023] The 5G NR Sub-6 GHz band processing module is used to perform baseband and radio frequency processing of 5G signals.

[0024] This invention also provides a method for a low-Earth orbit satellite terminal to adaptively access a 5G network. After the terminal is powered on, it performs strength and quality detection on both the reference signal from the terrestrial 5G base station and the 5G reference signal from the satellite link's receiving channel. If a usable network signal is detected only in the terrestrial direct link, the terminal decides to access the 5G network through the terrestrial base station. If usable network signals are detected in both the terrestrial direct link and the satellite relay link, the terminal still accesses the 5G network through the terrestrial base station. If a usable network signal is detected only in the satellite relay link, the terminal accesses the 5G network through the satellite relay link.

[0025] The beneficial effects of this invention are as follows: By using this invention, satellite terminals can fully leverage the respective advantages of accessing 5G via terrestrial networks and accessing 5G via satellite relay, providing users with optimal 5G communication services at minimal cost with relatively small hardware increases. Adaptive handover can also improve the user experience and promote the rapid deployment and widespread adoption of low-Earth orbit communication services. Attached Figure Description

[0026] Figure 1 This is the system architecture upon which the satellite terminal of this invention relies.

[0027] Figure 2 This is the architecture of the satellite terminal 5G access adaptive switching function of the present invention.

[0028] Figure 3This invention describes the adaptive switching process for 5G access on satellite terminals. Detailed Implementation

[0029] The specific embodiments of the present invention will be further described below with reference to the accompanying drawings and specific examples.

[0030] The system architecture upon which the satellite terminal of this invention relies is as follows: Figure 1 As shown, the system consists of a satellite terminal, low-Earth orbit satellites, ground gateway stations, satellite 5G base stations, ground 5G base stations, and a 5G core network. The satellite terminal is a device that continuously provides users with the best 5G communication service. Data generated by users can be directly transmitted to the terminal or accessed through the terminal to access the Internet. The terminal automatically selects whether to access the 5G network via satellite relay or directly via a ground base station.

[0031] Low-orbit satellites can perform frequency conversion, amplification, and forwarding of satellite 5G downlink signals from ground gateway stations and satellite 5G uplink signals from terminals.

[0032] The ground gateway station will amplify and forward the 5G downlink signal from the satellite 5G base station and the satellite 5G uplink signal from the satellite.

[0033] Satellite 5G base stations are also terrestrial 5G base stations, dedicated to interacting with terrestrial gateway stations to exchange 5G signals. They achieve beam coverage of ground areas by relaying the SSB signals from the 5G base station via satellite frequency conversion. They also respond to uplink signals from terminals originating from the satellite.

[0034] A terrestrial 5G base station is a 5G base station deployed on the ground to enable ordinary 5G user terminals to access the 5G network.

[0035] The 5G core network is the equipment deployed by operators for their standalone 5G networks. Together with terrestrial 5G base stations, it forms the ground-based 5G network coverage.

[0036] Taking a 5G network operating in TDD mode on the n41 frequency band, with both satellite uplink and downlink frequencies in the Ku band as an example, specific embodiments of the present invention are described below. Figure 2 , 3 As shown:

[0037] 1) Both the transmitting and receiving satellite antennas operate in the Ku band. To improve the antenna gain when transmitting and receiving data, a phased array antenna is used.

[0038] 2) The upconversion power amplifier module converts the 5G uplink signal operating in the n41 frequency band to the Ku frequency band. Similarly, the downconversion power amplifier module downconverts the Ku frequency band signal to the n41 frequency band.

[0039] 3) The 5G signal of the n41 band output by the downconversion amplifier module is divided into two identical parts by the power divider. One part is prepared to be sent to the 5G processing module, and the other part is sent to the adaptive handover decision module for signal analysis to ensure the concurrency of the two parts.

[0040] 4) The broadcast signal emitted by the terrestrial 5G base station is received by the 5G antenna and enters the hardware path of the terminal. It is then split into two by a power divider. One part is prepared to be sent to the 5G processing module, and the other part is sent to the adaptive handover decision module for signal analysis to ensure the concurrency of the two parts.

[0041] 5) After the adaptive switching decision module determines the access method to be prepared, the link switching switch connects the radio frequency path of the access method to the 5G processing module.

[0042] 6) At the same time, since it is a TDD mode, the radio frequency signal of the 5G module has been multiplexed inside the 5G module. The same radio frequency pin is used as a radio frequency input pin and a radio frequency output pin at different times. Therefore, for satellite relay access with independent transmit and receive channels, a transmit / receive switching switch is needed to time-division switch the transmit and receive signals of the two circuits.

[0043] 7) The 5G antenna module consists of 4 sub-antennas. Since it is in TDD mode, there are also four radio frequency paths between the antenna and the 5G module. Therefore, the power divider group 2 also consists of 4 power dividers, each power divider corresponding to one radio frequency path.

[0044] 8) After the satellite terminal is powered on, the adaptive handover decision module performs RSRP strength and RSRQ quality detection on the reference signals (PSS, SSS and PBCH signals) of the ground 5G base station, as well as the strength and quality of the 5G reference signals from the satellite link receiving channel.

[0045] 9) If an available network signal is detected only on a direct ground link, then it is decided to access the 5G network through a ground 5G base station;

[0046] 10) If a usable network signal is detected only on the satellite relay link, then access the 5G network via the satellite relay link.

[0047] 11) When both links detect 5G network signals, it is decided to access the 5G network through the ground base station;

[0048] 12) If the terminal previously accessed the 5G network via a satellite relay link, and now a usable network signal is detected on the ground direct access link, the terminal path selection will switch to access via a ground 5G base station, and the 5G processing module will re-enter the network.

[0049] It should be noted that the above description is merely illustrative and explanatory of the present invention. Those skilled in the art should understand that any modifications and substitutions to the present invention fall within the scope of protection of the present invention.

Claims

1. A method for adaptive access to a 5G network by a low-Earth orbit satellite terminal, characterized in that, The process includes the following steps: Step 1: After the satellite terminal is powered on, it simultaneously detects available reference signals in both the ground direct link and the satellite relay link, as detailed below: The available reference signal for detecting ground direct links refers to the strength and quality of the reference signal for detecting ground 5G base stations; The available reference signal for satellite relay link detection refers to the strength and quality of the reference signal for detecting satellite 5G base stations; Step 2: Determine the access method for the satellite terminal's 5G network, as follows: If only a usable reference signal is detected on the ground direct link, then access to the 5G network will be selected through a ground 5G base station; If only the satellite relay link detects a usable reference signal, then access to the 5G network will be selected via the satellite relay link; If both the ground direct link and the satellite relay link detect available reference signals, then access to the 5G network via the ground 5G base station will be given priority.

2. The method for adaptive access to a 5G network by a low-orbit satellite terminal as described in claim 1, characterized in that, When a satellite terminal is currently accessing the 5G network via a satellite relay link, and subsequently detects a usable reference signal on a direct ground link, the access method will be switched to accessing the 5G network via a ground 5G base station, and the satellite terminal's 5G processing module will be controlled to re-enter the network.

3. The method for adaptive access to a 5G network by a low-orbit satellite terminal as described in claim 1, characterized in that, The reference signals include PSS, SSS and PBCH signals, with RSRP as the intensity detection index and RSRQ as the quality detection index.

4. A system for adaptive access to a 5G network by a low-Earth orbit satellite terminal, used to implement the method as described in any one of claims 1 to 3, characterized in that, The system includes a satellite terminal, a low-orbit satellite, a ground gateway station, a satellite 5G base station, a ground 5G base station, and a 5G core network; The low-orbit satellite is used to frequency-convert, amplify, and forward satellite 5G downlink signals from ground gateway stations and satellite 5G uplink signals from satellite terminals. The ground gateway station is used to perform frequency conversion, amplification, and forwarding of 5G downlink signals from satellite 5G base stations and satellite 5G uplink signals from low-orbit satellites; The satellite 5G base station is deployed on the ground to interact with ground gateway stations to exchange 5G signals. It also transmits the SSB signal of the satellite 5G base station through low-orbit satellite frequency conversion to achieve beam coverage in the ground area, and responds to uplink signals from satellite terminals from low-orbit satellites. The 5G core network and terrestrial 5G base stations together form a terrestrial 5G network.

5. A system for adaptive access to a 5G network by a low-orbit satellite terminal as described in claim 4, characterized in that, The satellite terminal includes: a transmitting satellite antenna module, a receiving satellite antenna module, an up-conversion power amplifier module, a down-conversion amplifier module, a power divider 1 module, a transmit / receive switching switch module, a 5G antenna module, a power divider group 2 module, an adaptive switching decision module, a link switching switch module, and a 5G processing module.

6. A system for adaptive access to a 5G network by a low-orbit satellite terminal as described in claim 5, characterized in that, The satellite antenna module is used to transmit 5G uplink signals that have been frequency-converted to the uplink frequency of the low-orbit satellite to the low-orbit satellite. The receiving satellite antenna module is used to receive 5G downlink signals from low-Earth orbit satellites at the downlink frequency of the low-Earth orbit satellites. The upconversion power amplifier module is used to convert the standard 5G uplink signal from the 5G processing module to the low-orbit satellite uplink frequency, and to amplify the power of the converted signal. The downconversion amplifier module is used to convert the 5G downlink signal from the low-Earth orbit satellite at the low-Earth orbit satellite downlink frequency to the standard 5G frequency, and amplify the converted signal.

7. A system for adaptive access to a 5G network by a low-orbit satellite terminal as described in claim 5, characterized in that, The power divider module is used to split the standard 5G signal from the downconversion amplifier module into two paths, one of which is transmitted to the adaptive switching decision module and the other is transmitted to the transceiver switching module. The transmit / receive switching module is used to switch the standard 5G signal between transmit and receive according to TDD mode, so that only one signal is connected to the link switching module.

8. A system for adaptive access to a 5G network by a low-orbit satellite terminal as described in claim 7, characterized in that, The 5G antenna module is used to convert standard 5G signals between electrical signals and radio wave signals; The power divider 2 module is used to divide the standard 5G downlink signal from the 5G antenna module into two paths, one of which is transmitted to the adaptive handover decision module and the other of which is transmitted to the link handover switch module. The number of the power divider group 2 modules is the same as the number of sub-antennas included in the 5G antenna module.

9. A system for adaptive access to a 5G network by a low-orbit satellite terminal as described in claim 7, characterized in that, The adaptive switching decision module is used to calculate the signal strength and signal quality of the standard 5G downlink signal from the satellite relay link and the standard 5G downlink signal from the ground direct link, respectively, to obtain the network signal evaluation results of the two access methods, and to determine the current access method based on the evaluation results. The link switching module is used to connect the 5G processing module to the signal path of the corresponding access path according to the access path determined by the adaptive switching decision module.

10. A system for adaptive access to a 5G network by a low-orbit satellite terminal as described in claim 7, characterized in that, The 5G processing module is used to perform baseband processing and radio frequency processing of 5G signals; Both the transmitting and receiving satellite antenna modules are phased array antennas operating in the Ku band to improve antenna gain during data transmission and reception.

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