A method for agile coverage of satellite hopping beams

Abstract

The present invention relates to a method for agile coverage of satellite hopping beams, belonging to the field of network control in satellite communication. This method divides the beams formed by the phased array antenna into access beams and service beams, scans the access beams wave by wave position within the satellite's earth view field to ensure the opportunistic access of satellite terminals; after successful access, service beams are allocated, and the hopping time and residence duration of the service beams are dynamically generated according to the location and actual traffic volume of the satellite terminals, so as to achieve agile coverage. The present invention is applicable to high and low earth orbit satellites with on-board processing capabilities and configured with phased array antennas, can realize the opportunistic access and on-demand coverage of the satellite to ground terminals, and ensure the efficient utilization of beam resources.

Description

Technical Field

[0001] The present invention relates to the field of satellite communication technology, and particularly focuses on the related technologies of network control in the field of satellite communication. It can be used in high and low orbit satellites to achieve opportunistic access of satellites to ground terminals and on-demand coverage, and solve the problem of efficient utilization of phased array beam resources. Background Art

[0002] Satellite communication has a history of more than half a century. Due to its series of advantages such as global coverage, being unrestricted by ground obstacles, and being able to be deployed quickly, it can provide stable communication capabilities to multi-users across continents and oceans, and can also provide effective information transmission in area emergencies where the location, time, and intensity are unpredictable. Therefore, satellite communication has become one of the irreplaceable core communication means. Satellite communication technology has also become an important indicator to measure a country's core competitiveness.

[0003] In recent years, with the development of on-board processing technology, the combination of phased array antennas with on-board modulation, demodulation, network control, routing, and switching has gradually become the standard configuration of communication satellite payloads. Due to the characteristics of fast beamforming of phased array antennas, compared with traditional reflector antennas, they have certain advantages in terms of scanning time and shaping ability. By designing a reasonable hopping beam strategy, without reducing antenna gain and radiation power, etc., through time-sharing coverage, communication guarantee for wide-area dispersed users within the satellite's earth-viewing field can be achieved.

[0004] Currently, the research on satellite hopping beam technology mostly focuses on the optimization of hopping beam strategies, and the access of hopping beams mainly adopts the pre-upload method, which is difficult to meet the needs of users' opportunistic access and on-demand coverage. Summary of the Invention

[0005] In view of this, the present invention proposes a method for agile coverage of satellite hopping beams, which can be used in high and low orbit satellites with on-board processing to achieve opportunistic access of satellites to ground terminals and on-demand coverage, and ensure the efficient utilization of phased array beam resources.

[0006] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0007] A method for agile coverage of satellite hopping beams, which is applied to high / low orbit satellites with on-board processing; the satellite is configured with on-board phased array antennas, on-board network control, on-board switching, on-board demodulators, and on-board modulators. The receive and transmit beams of the on-board phased array antennas are independently controlled. The receive beam is controlled by the on-board network control, and the transmit beam is controlled by the on-board modulator. The access process is jointly completed by the satellite, the ground network management center, and the satellite terminal. The method includes the following steps:

[0008] The network management center sets a group of receive / transmit beams of the spaceborne phased array antenna as access beams, and the receive / transmit beams of other components as service beams;

[0009] The network management center configures the scanning pattern of the access beam for the spaceborne network control. The spaceborne network control controls the access beam to perform step-by-step beam position jumps within the satellite's earth viewing field according to the scanning pattern, and the dwell time at each beam position is the same;

[0010] The network management center configures the scanning pattern of the access beam for the spaceborne modulator. The spaceborne modulator controls the transmit access beam to perform step-by-step beam position jumps within the satellite's earth viewing field according to the scanning pattern, and the dwell time at each beam position is the same. During the dwell period, the spaceborne modulator broadcasts a satellite-earth notice to the currently covered beam position, and the satellite-earth notice includes synchronization information;

[0011] After the satellite terminal powers on, it stays on the frequency point of the transmit access beam. When the transmit access beam scans to its location, the satellite terminal captures the transmit access beam signal, performs downlink synchronization, and receives the satellite-earth notice;

[0012] The satellite terminal sends an access request containing the terminal location information to the spaceborne network control of the satellite;

[0013] After receiving the access request, the spaceborne network control allocates receive / transmit service beams for the satellite terminal, combines the terminal location information in the access request and the service requirements of the satellite terminal, generates the scanning pattern of the receive service beam and the time slot allocation plan during the dwell period at each beam position, and controls the receive service beam to perform jumps according to the scanning pattern of the receive service beam;

[0014] The spaceborne network control sends the time slot allocation plan for each beam position and the mapping relationship between the satellite terminal address and the beam position to the spaceborne modulator;

[0015] The spaceborne modulator generates a broadcast burst for the time slot allocation plan of each beam position, uses the duration of the broadcast burst as the dwell time of the transmit service beam at the corresponding beam position, and forms the broadcast burst scanning pattern of the transmit service beam for each beam position;

[0016] The spaceborne modulator generates a data burst for the service data in the current downlink queue, looks up the mapping relationship between the satellite terminal address and the beam position according to the destination terminal address in the data burst, determines the beam position, and uses the duration of the data burst as the dwell time of the transmit service beam at the corresponding beam position, and forms the data burst scanning pattern of the transmit service beam for each beam position;

[0017] The spaceborne modulator combines the broadcast burst scanning pattern and the data burst scanning pattern into the scanning pattern of the transmit service beam, and controls the transmit service beam to perform jumps according to the scanning pattern of the transmit service beam;

[0018] The spaceborne network control sends access beams to the satellite terminal to send the allocated service beam information. The satellite terminal switches from the access beam to the service beam to complete the signal capture, downlink synchronization, and receiving of the time slot allocation plan of the service beam;

[0019] The satellite terminal calculates the sending time of the service data according to the time slot allocation plan and sends the service data at this time.

[0020] Specifically, in each of the above steps, the wave position is an area projected by the phased array transmit / receive beam on the ground; the scanning pattern consists of a wave position sequence and a dwell time. The phased array transmit / receive beam jumps between different wave positions according to the order given by the sequence.

[0021] Specifically, in each of the above steps, the scanning periods of the phased array antenna transmit / receive beams are the same, and the scanning control timings are synchronized: the start time of the transmit beam scanning period is ahead of the start time of the receive beam scanning period by a fixed time Delay, and Delay is greater than the round-trip satellite-ground time delay.

[0022] Specifically, in each of the above steps, the phased array antenna transmit / receive access beams use the same scanning pattern.

[0023] Specifically, in step E, the method for the satellite terminal to determine the access application sending time includes the following steps:

[0024] The satellite terminal measures its round-trip satellite-ground time delay RTT;

[0025] After the satellite terminal completes downlink synchronization under the transmit access beam, it waits for a time of (Delay - RTT) and then sends an access application.

[0026] Specifically, in step L, the method for the satellite terminal to determine the service data sending time includes the following steps:

[0027] The satellite terminal measures its round-trip satellite-ground time delay RTT;

[0028] The satellite terminal receives a broadcast burst containing a time slot allocation plan and determines the relative offset Offset1 of this burst from the start time of the scanning period according to the time synchronization information marked in the broadcast burst;

[0029] The satellite terminal analyzes the time slot allocation plan and determines the relative offset Offset2 of the service data sending time of this terminal from the start time of the scanning period;

[0030] After the satellite terminal receives the broadcast burst under the transmit service beam, it waits for a time of (Offset2 - Offset1 + Delay - RTT) and then sends the service data.

[0031] The present invention has the following beneficial effects compared with the background technology:

[0032] 1. The present invention adopts a control method combining scanning and beam agility, which can realize the opportunistic access of a satellite terminal based on a phased array antenna, and dynamically control the beam hopping of the phased array antenna according to the position distribution and service model of the satellite terminal to achieve on-demand coverage.

[0033] 2. This method does not need to rely on the cooperation of other beams, and can effectively improve the access ability of the phased array beam and the resource utilization efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] FIG. 1 is a schematic diagram of an application scenario of a beam agility coverage method for satellite beam hopping according to an embodiment of the present invention;

[0035] FIG. 2 is a flowchart of opportunistic access according to an embodiment of the present invention;

[0036] FIG. 3 is a timing control diagram of beam hopping according to an embodiment of the present invention. EMBODIMENT

[0037] The present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0038] As Figure 1 shown, it is an application scenario of a beam agility coverage method for satellite beam hopping. The access beam scans each wave position in the field of view according to the scanning pattern pre-injected by the network management center. When the satellite terminal at wave position 5 receives the star-earth notice when the transmit access beam scans to its location and sends an access request when the receive access beam scans to its location subsequently; the receive and transmit service beams perform on-demand coverage on wave positions 1 and 5 where there are satellite terminals. When the satellite terminal is covered by the receive service beam at its wave position, it receives the time slot allocation plan and sends service data; the transmit service beam controls beam hopping according to the downlink queue and synchronously irradiates the corresponding wave position when sending data.

[0039] As Figure 2 shown, the method has the following steps:

[0040] The network management center sets a group of receive / transmit beams of the spaceborne phased array antenna as access beams, and the other components of the receive / transmit beams as service beams;

[0041] The network management center configures the scanning pattern of the receive access beam to the spaceborne network control. The spaceborne network control controls the receive access beam to perform wave position hopping one by one within the satellite's field of view of the earth according to the scanning pattern, and the residence time at each wave position is the same;

[0042] The network management center configures the scanning pattern of the transmit access beam for the on-board modulator. The on-board modulator controls the transmit access beam to perform step-by-step beam position jumps within the satellite's earth-viewing field according to the scanning pattern, and the dwell time at each beam position is the same. During the dwell period, the on-board modulator broadcasts a satellite-earth notice to the current covered beam position, including: synchronization information, the scanning pattern of the receive access beam, etc.;

[0043] After the satellite terminal powers on, it stays on the frequency point of the transmit access beam. When the transmit access beam scans to its location, the satellite terminal captures the transmit access beam signal, performs downlink synchronization, and receives the satellite-earth notice;

[0044] The satellite terminal sends an access request containing the terminal location information to the on-board network control of the satellite;

[0045] After receiving the access request, the on-board network control allocates receive and transmit service beams for the satellite terminal. Combining the terminal location information in the access request and the service requirements of the satellite terminal, it generates the scanning pattern of the receive service beam and the time slot allocation plan during the dwell period at each beam position, and controls the receive service beam to perform jumps according to the scanning pattern of the receive service beam;

[0046] The on-board network control sends the time slot allocation plan for each beam position and the mapping relationship between the satellite terminal address and the beam position to the on-board modulator;

[0047] The on-board modulator generates a broadcast burst for the time slot allocation plan of each beam position, uses the duration of the broadcast burst as the dwell time of the transmit service beam at the corresponding beam position, and forms the broadcast burst scanning pattern of the transmit service beam for each beam position;

[0048] The on-board modulator generates a data burst for the service data in the current downlink queue. According to the destination terminal address in the data burst, it looks up the mapping relationship between the satellite terminal address and the beam position to determine the beam position, and uses the duration of the data burst as the dwell time of the transmit service beam at the corresponding beam position, and forms the data burst scanning pattern of the transmit service beam for each beam position;

[0049] The on-board modulator combines the broadcast burst scanning pattern and the data burst scanning pattern into the scanning pattern of the transmit service beam, and controls the transmit service beam to perform jumps according to the scanning pattern of the transmit service beam;

[0050] The on-board network control sends the service beam information allocated for the satellite terminal to the satellite terminal through the transmit access beam. The satellite terminal switches from the access beam to the service beam, and completes the signal capture, downlink synchronization and time slot allocation plan reception of the receive service beam;

[0051] The satellite terminal calculates the transmission time of the service data according to the time slot allocation plan, and sends the service data at this time.

[0052] Such as Figure 3As shown, the method for the satellite terminal to determine the access request sending time in step E includes the following steps:

[0053] The satellite terminal measures its round-trip satellite-ground delay RTT;

[0054] After the satellite terminal completes downlink synchronization in the transmitting access beam, it waits for a time of (Delay - RTT) and then sends an access request.

[0055] As Figure 3 shown, the method for the satellite terminal to determine the service data sending time in step L includes the following steps:

[0056] The satellite terminal measures its round-trip satellite-ground delay RTT;

[0057] The satellite terminal receives a broadcast burst containing a time slot allocation plan, and determines the relative offset Offset1 between this burst and the start time of the scan cycle according to the time synchronization information marked in the broadcast burst;

[0058] The satellite terminal analyzes the time slot allocation plan and determines the relative offset Offset2 between the service data sending time of this terminal and the start time of the scan cycle;

[0059] After the satellite terminal receives the broadcast burst in the transmitting service beam, it waits for a time of (Offset2 - Offset1 + Delay - RTT) and then sends service data.

[0060] In summary, the present invention uniquely creates a method for agile coverage of satellite hopping beams. This method divides the beams formed by the phased array antenna into access beams and service beams, scans the access beams wave by wave position within the satellite's field of view of the earth to ensure the opportunistic access of satellite terminals; after successful access, service beams are allocated, and the hopping time and residence duration of the service beams are dynamically generated according to the location and actual traffic volume of the satellite terminal to achieve agile coverage. The present invention is applicable to high and low earth orbit satellites with on-board processing capabilities and configured with phased array antennas, and can achieve the opportunistic access and on-demand coverage of satellite to ground terminals, ensuring the efficient utilization of phased array beam resources.

[0061] Those of ordinary skill in the art can understand that implementing a method for agile coverage of satellite hopping beams can be completed by hardware or software related to program instructions. When this program is executed, it executes the steps including the above method embodiments.

[0062] Finally, it should be noted that the above are only the preferred examples of the present invention. Although the present invention has been described in detail with reference to the above embodiments, for those skilled in the art, they can still modify the technical solutions of the foregoing embodiments, or perform equivalent replacements on other technical features. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A method for agile coverage of satellite hopping beams, characterized in that, it is applied to high / low-orbit satellites with on-board processing capabilities; the satellite is configured with an on-board phased array antenna, on-board network control, on-board switching, on-board demodulator, and on-board modulator. The receive and transmit beams of the on-board phased array antenna are independently controlled. The receive beam is controlled by the on-board network control, and the transmit beam is controlled by the on-board modulator. The access process is jointly completed by the satellite, the ground network management center, and the satellite terminal; the method includes the following steps: A. The network management center sets a group of receive / transmit beams of the on-board phased array antenna as access beams, and the receive / transmit beams of other components as service beams; B. The network management center configures the scanning pattern of the access beam for the on-board network control. The on-board network control controls the receive access beam to perform step-by-step beam position hopping within the satellite's earth viewing field according to the scanning pattern, and the dwell time at each beam position is the same; C. The network management center configures the scanning pattern of the access beam for the on-board modulator. The on-board modulator controls the transmit access beam to perform step-by-step beam position hopping within the satellite's earth viewing field according to the scanning pattern, and the dwell time at each beam position is the same; during the dwell period, the on-board modulator broadcasts a satellite-earth notice to the current covered beam position, and the satellite-earth notice includes synchronization information; D. After the satellite terminal is powered on, it stays on the frequency point of the transmit access beam. When the transmit access beam scans to its location, the satellite terminal captures the transmit access beam signal, performs downlink synchronization, and receives the satellite-earth notice; E. The satellite terminal sends an access request containing the terminal's location information to the on-board network control of the satellite; F. After receiving the access request, the on-board network control allocates receive / transmit service beams for the satellite terminal. Combining the terminal location information in the access request and the service requirements of the satellite terminal, it generates the scanning pattern of the receive service beam and the time slot allocation plan during the dwell period at each beam position, and controls the receive service beam to perform hopping according to the scanning pattern of the receive service beam; G. The on-board network control sends down the time slot allocation plan for each beam position and the mapping relationship between the satellite terminal address and the beam position to the on-board modulator; H. The on-board modulator generates a broadcast burst for the time slot allocation plan of each beam position, and uses the duration of the broadcast burst as the dwell time of the transmit service beam at the corresponding beam position to form the broadcast burst scanning pattern of the transmit service beam for each beam position; I. The on-board modulator generates a data burst for the service data in the current downlink queue. According to the destination terminal address in the data burst, it searches for the mapping relationship between the satellite terminal address and the beam position, determines the beam position, and uses the duration of the data burst as the dwell time of the transmit service beam at the corresponding beam position to form the data burst scanning pattern of the transmit service beam for each beam position; J. The on-board modulator combines the broadcast burst scanning pattern and the data burst scanning pattern into the scanning pattern of the transmit service beam, and controls the transmit service beam to perform hopping according to the scanning pattern of the transmit service beam; K. The on-board network control sends down the service beam information allocated for the satellite terminal to the satellite terminal through the transmit access beam. The satellite terminal switches from the access beam to the service beam, and completes the signal capture, downlink synchronization, and time slot allocation plan reception of the receive service beam; L. The satellite terminal calculates the transmission time of the service data according to the time slot allocation plan and sends the service data at this time.

2. A method for agile coverage of satellite hopping beams according to claim 1, characterized in that, The wave position is an area projected by the phased array transmit / receive beam on the earth's surface; the scanning pattern consists of a wave position sequence and a dwell time. The transmit / receive beam of the spaceborne phased array antenna jumps between different wave positions in the order given by the sequence.

3. A method for agile coverage of satellite hopping beams according to claim 2, characterized in that, The scanning periods of the transmit / receive beams of the spaceborne phased array antenna are the same, and the scanning control timings are synchronized. The start time of the transmit beam scanning period is ahead of the start time of the receive beam scanning period by a fixed time Delay, and Delay is greater than the round-trip time delay between the satellite and the ground.

4. A method for agile coverage of satellite hopping beams according to claim 3, characterized in that, The transmit / receive access beams of the spaceborne phased array antenna use the same scanning pattern.

5. A method for agile coverage of satellite hopping beams according to claim 4, characterized in that, In step E, the method for the satellite terminal to determine the access application sending time is: A. The satellite terminal measures its round-trip time delay RTT between the satellite and the ground; B. After the satellite terminal completes downlink synchronization under the transmit access beam, it waits for a time of Delay - RTT and sends an access application.

6. A method for agile coverage of satellite hopping beams according to claim 1, characterized in that, In step L, the method for the satellite terminal to determine the service data sending time is: A. The satellite terminal measures its round-trip time delay RTT between the satellite and the ground; B. The satellite terminal receives a broadcast burst containing a time slot allocation plan, and determines the relative offset Offset1 between this burst and the start time of the scanning period according to the time synchronization information marked in the broadcast burst; C. The satellite terminal analyzes the time slot allocation plan and determines the relative offset Offset2 between the service data sending time of this terminal and the start time of the scanning period; D. After the satellite terminal receives the broadcast burst under the transmit service beam, it waits for a time of Offset2 - Offset1 + Delay - RTT and sends service data.

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