阅读说明：本技术 用于测试卫星通信系统性能的系统及方法、装置、电子设备 (System, method and device for testing performance of satellite communication system and electronic equipment ) 是由 马玉娟 李侠宇 徐冰玉 柳明 刘海蛟 于 2021-08-18 设计创作，主要内容包括：本申请涉及卫星通信技术领域,公开一种用于测试卫星通信系统性能的系统,包括：测试卫星、用户终端、信关站、用户链路信道模拟及切换装置和馈电链路信道模拟及切换装置。通过测试卫星、用户终端、信关站建立卫星通信系统,在测试卫星与用户终端之间设置用户链路信道模拟及切换装置,并在测试卫星与信关站之间设置馈电链路信道模拟及切换装置,通过用户链路信道模拟及切换装置和馈电链路信道模拟及切换装置切换不同的信道,以模拟测试卫星移动时卫星信道及信关站信道的改变,进而通过用户终端或信关站生成并传输信号,从而能够实现对卫星通信系统移动性的管理性能的测试。本申请还公开一种用于测试卫星通信系统性能的方法、装置和电子设备。(The application relates to the technical field of satellite communication, and discloses a system for testing the performance of a satellite communication system, which comprises: the system comprises a test satellite, a user terminal, a gateway station, a user link channel simulation and switching device and a feeder link channel simulation and switching device. A satellite communication system is established through a test satellite, a user terminal and a gateway station, a user link channel simulation and switching device is arranged between the test satellite and the user terminal, a feeder link channel simulation and switching device is arranged between the test satellite and the gateway station, different channels are switched through the user link channel simulation and switching device and the feeder link channel simulation and switching device so as to simulate the change of the satellite channel and the gateway station channel when the test satellite moves, and then signals are generated and transmitted through the user terminal or the gateway station, so that the test of the management performance of the satellite communication system mobility can be realized. The application also discloses a method, a device and electronic equipment for testing the performance of the satellite communication system.)

1. A system for testing the performance of a satellite communications system, comprising:

a test satellite provided with a plurality of satellite channels;

the user terminal is used for generating a reverse link signal and transmitting the reverse link signal to the gateway station through the satellite channel of the test satellite;

the gateway station is used for generating a forward link signal and transmitting the forward link signal to the user terminal through a satellite channel of the test satellite; the gateway station is provided with a plurality of gateway station channels;

one end of the user link channel simulation and switching device is connected with the user terminal, and the other end of the user link channel simulation and switching device is connected with the test satellite; the user link channel simulation and switching device is used for simulating channel change caused by the movement of the test satellite and the user terminal and switching the satellite channel;

one end of the feed link channel simulation and switching device is connected with the gateway station, and the other end of the feed link channel simulation and switching device is connected with the test satellite; the feeder link channel simulation and switching device is used for simulating channel change caused by movement of the test satellite and switching the satellite channel and/or the gateway station channel.

2. The system of claim 1, wherein the test satellite comprises a first satellite load and a second satellite load; the first satellite load is provided with a first satellite channel and a second satellite channel, the second satellite load is provided with a third satellite channel, and the first satellite channel and the second satellite channel are different beam channels of the first satellite load; the user link channel simulation and switching device comprises a user link channel simulator, a first power control module and a first switching module, wherein the first power control module is used for controlling the power of a channel; the user terminal is connected with the user link channel simulator through the first power control module and the first switching module in sequence; the user link channel simulator communicates a first satellite channel of the first satellite payload with the second satellite channel; the user link channel simulator is also in communication with a third satellite channel of the second satellite payload.

3. The system of claim 2 wherein said first power control module is a first attenuator, said first switching module is a first switch, and said subscriber link channel simulation and switching means switches between said first satellite channel, said second satellite channel, and said third satellite channel via said first switch.

4. The system of claim 2 wherein said first power control module is a first attenuator and said first switching module is a first power splitter, said subscriber link channel simulator and switching device adjusting signal strengths of said first satellite channel, said second satellite channel and said third satellite channel via said subscriber link channel simulator to effect switching between said first satellite channel, said second satellite channel and said third satellite channel.

5. The system of claim 1, wherein the test satellite comprises a first satellite load and a second satellite load; the first satellite load is provided with a fourth satellite channel, and the second satellite load is provided with a fifth satellite channel; the gateway stations comprise a first sub-gateway station and a second sub-gateway station, the first sub-gateway station is provided with a first gateway station channel, and the second sub-gateway station is provided with a second gateway station channel; the feeder link channel simulation and switching device comprises a feeder link simulator, a second power control module and a second switching module; the second power control module is used for controlling the power of the channel; the second power control module is connected with the feeder link simulator through the second switching module, and the feeder link simulator is communicated with a fourth satellite channel of the first satellite load; the feeder link simulator is also communicated with a fifth satellite channel of the second satellite load; the second power control module is communicated with a first gateway station channel of the first sub-gateway station, and the second power control module is also communicated with a second gateway station channel of the second sub-gateway station.

6. The system of claim 5, wherein the second power control module comprises a second attenuator and a third attenuator; the second switching module comprises a second switch and a third switch; the second attenuator is connected with the feed link channel simulator sequentially through the third selector switch and the second selector switch; the third attenuator is connected with the feed link channel simulator sequentially through the third selector switch and the second selector switch; the feeder link channel simulator is communicated with a fourth satellite channel of the first satellite load, and is also communicated with a fifth satellite channel of the second satellite load; the second attenuator is communicated with a first gateway station channel of the first sub-gateway station, and the third attenuator is communicated with a second gateway station channel of the second sub-gateway station; the feeder link channel simulation and switching device switches the fourth satellite channel and the fifth satellite channel through the second switch; the feeder link channel simulation and switching device switches between the first gateway station channel and the second gateway station channel through the third switch.

7. The system of claim 5, wherein the second power control module comprises a second attenuator and a third attenuator; the second switching module comprises a second power divider and a third power divider; the second attenuator is connected with the feeder link channel simulator sequentially through the third power divider and the second power divider; the third attenuator is connected with the feeder link channel simulator sequentially through the third power divider and the second power divider; the feeder link channel simulator is communicated with a fourth satellite channel of the first satellite load, and is also communicated with a fifth satellite channel of the second satellite load; the second attenuator is communicated with a first gateway station channel of the first sub-gateway station, and the third attenuator is communicated with a second gateway station channel of the second sub-gateway station; the feeder link channel simulator and switching device regulates the signal strength of the fourth satellite channel and the signal strength of the fifth satellite channel through the feeder link channel simulator so as to switch between the fourth satellite channel and the fifth satellite channel; the feeder link channel simulator and switching device adjusts the signal strength of the first and second gateway station channels through the feeder link channel simulator to perform switching between the first and second gateway station channels.

8. A method for testing the performance of a satellite communication system, the method being implemented on the system for testing the performance of a satellite communication system according to any one of claims 1 to 7, the method comprising:

switching communication channels in the process of satellite communication between the user terminal and the gateway station;

acquiring a sending signal and a receiving signal of the user terminal and the gateway station under different communication channel states;

performing signal analysis on the sending signal and the receiving signal to obtain an analysis result;

and obtaining a test result according to the analysis result.

9. An apparatus for testing performance of a satellite communication system, comprising a processor and a memory having stored thereon program instructions, wherein the processor is configured to, upon execution of the program instructions, perform the method for testing performance of a satellite communication system of claim 8.

10. An electronic device comprising the apparatus for testing the performance of a satellite communication system of claim 9.

Technical Field

The present disclosure relates to the field of satellite communications technologies, and in particular, to a system, a method, an apparatus, and an electronic device for testing performance of a satellite communications system.

Background

Satellite communication systems, which are generally composed of gateway stations, satellites and user terminals, are an effective means for achieving ground and air, ground and ground communications using satellite communication payloads as communication carriers. The system can provide information network service for various users such as land, ocean, sky and the like, and has wide application scenes. The management of the location information, security and service continuity aspects of a satellite communication system is referred to as mobility management of the satellite communication system. For a medium-low orbit satellite, the moving speed and the earth rotation speed are not the same, and as the satellite continuously and rapidly moves, the coverage area of a beam channel of the satellite and the access positions of a user terminal and a gateway station are continuously changed, so that the continuity and the reliability of a communication service are influenced. Therefore, mobility management of a satellite communication system is one of the key technologies for constructing a satellite communication system. However, there is currently a lack of a method for testing the management performance of the mobility of a satellite communication system.

Disclosure of Invention

The following presents a simplified summary in order to provide a basic understanding of some aspects of the disclosed embodiments. This summary is not an extensive overview nor is intended to identify key/critical elements or to delineate the scope of such embodiments but rather as a prelude to the more detailed description that is presented later.

The embodiment of the disclosure provides a system, a method and a device for testing the performance of a satellite communication system, and electronic equipment, so as to test the management performance of the mobility of the satellite communication system.

In some embodiments, a system for testing the performance of a satellite communications system, comprises: a test satellite provided with a plurality of satellite channels; the user terminal is used for generating a reverse link signal and transmitting the reverse link signal to the gateway station through the satellite channel of the test satellite; the gateway station is used for generating a forward link signal and transmitting the forward link signal to the user terminal through a satellite channel of the test satellite; the gateway station is provided with a plurality of gateway station channels; one end of the user link channel simulation and switching device is connected with the user terminal, and the other end of the user link channel simulation and switching device is connected with the test satellite; the user link channel simulation and switching device is used for simulating channel change caused by the movement of the test satellite and the user terminal and switching the satellite channel; one end of the feed link channel simulation and switching device is connected with the gateway station, and the other end of the feed link channel simulation and switching device is connected with the test satellite; the feeder link channel simulation and switching device is used for simulating channel change caused by movement of the test satellite and switching the satellite channel and/or the gateway station channel.

In some embodiments, a method for testing the performance of a satellite communication system, the method being implemented based on the system for testing the performance of a satellite communication system described above, the method comprising: switching communication channels in the process of satellite communication between the user terminal and the gateway station; acquiring a sending signal and a receiving signal of the user terminal and the gateway station under different communication channel states; performing signal analysis on the sending signal and the receiving signal to obtain an analysis result; and obtaining a test result according to the analysis result.

In some embodiments, an apparatus for testing performance of a satellite communication system includes a processor and a memory storing program instructions, the processor configured to, when executing the program instructions, perform the above-described method for testing performance of a satellite communication system.

In some embodiments, an electronic device comprises the above-described apparatus for testing the performance of a satellite communication system.

The system, the method, the device and the electronic equipment for testing the performance of the satellite communication system can achieve the following technical effects: the satellite communication system is established by a test satellite, a user terminal and a gateway station, signal transmission is carried out between the user terminal and the gateway station through a satellite channel, the satellite channel is switched by arranging a user link channel simulation and switching device between the test satellite and the user terminal, and a feeder link channel simulation and switching device is arranged between the test satellite and the gateway station to switch the satellite channel and/or the gateway station channel so as to simulate the change of the satellite channel and the gateway station channel when the test satellite moves, thereby realizing the test of the management performance of the mobility of the satellite communication system.

The foregoing general description and the following description are exemplary and explanatory only and are not restrictive of the application.

Drawings

One or more embodiments are illustrated by way of example in the accompanying drawings, which correspond to the accompanying drawings and not in limitation thereof, in which elements having the same reference numeral designations are shown as like elements and not in limitation thereof, and wherein:

FIG. 1 is a schematic diagram of a system for testing the performance of a satellite communications system provided by an embodiment of the present disclosure;

FIG. 2 is a schematic diagram of another system for testing the performance of a satellite communications system provided by an embodiment of the present disclosure;

FIG. 3-1 is a schematic diagram of a subscriber link of a system for testing the performance of a satellite communications system provided by embodiments of the present disclosure;

3-2 is a schematic diagram of a subscriber link of another system for testing the performance of a satellite communications system provided by an embodiment of the present disclosure;

FIG. 4-1 is a schematic illustration of a feeder link of a system for testing the performance of a satellite communications system provided by an embodiment of the present disclosure;

fig. 4-2 is a schematic diagram of a feeder link of another system for testing performance of a satellite communications system provided by an embodiment of the present disclosure;

FIG. 5 is a schematic diagram of a method for testing the performance of a satellite communication system according to an embodiment of the present disclosure;

fig. 6 is a schematic diagram of an apparatus for testing performance of a satellite communication system according to an embodiment of the disclosure.

Detailed Description

So that the manner in which the features and elements of the disclosed embodiments can be understood in detail, a more particular description of the disclosed embodiments, briefly summarized above, may be had by reference to the embodiments, some of which are illustrated in the appended drawings. In the following description of the technology, for purposes of explanation, numerous details are set forth in order to provide a thorough understanding of the disclosed embodiments. However, one or more embodiments may be practiced without these details. In other instances, well-known structures and devices may be shown in simplified form in order to simplify the drawing.

The terms "first," "second," and the like in the description and in the claims, and the above-described drawings of embodiments of the present disclosure, are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It should be understood that the data so used may be interchanged under appropriate circumstances such that embodiments of the present disclosure described herein may be made. Furthermore, the terms "comprising" and "having," as well as any variations thereof, are intended to cover non-exclusive inclusions.

The term "plurality" means two or more unless otherwise specified.

In the embodiment of the present disclosure, the character "/" indicates that the preceding and following objects are in an or relationship. For example, A/B represents: a or B.

The term "and/or" is an associative relationship that describes objects, meaning that three relationships may exist. For example, a and/or B, represents: a or B, or A and B.

The term "correspond" may refer to an association or binding relationship, and a corresponds to B refers to an association or binding relationship between a and B.

For satellite communication systems, tens, hundreds, or even thousands of satellites need to be deployed to cover the global communication area. Due to the high speed of satellite movement, the satellite communication process is frequently switched. Frequent switching may cause interruption, delay, etc. of user data transmission, and may increase overhead and complexity of the satellite communication system, and may cause link interruption under severe conditions, which may seriously affect quality of communication service.

A system for testing mobility management performance of a satellite communication system requires simulation of different handover scenarios, including: the method comprises the following steps of switching a user link intra-satellite beam, a user link inter-satellite switching scene, a feed link inter-satellite switching scene and a feed link gateway.

In a user link intra-satellite beam switching scenario, in order to increase coverage, a single test satellite generally supports multiple satellite channels, and different satellite channels have different working frequency bands and different coverage ranges. In addition to frequency division multiplexing, in some satellite designs, satellite channels are added by space division multiplexing. As the test satellite moves, the coverage area of the satellite channel moves, and the user terminal needs to switch between different satellite channels.

In the inter-satellite switching scenario of the user link, as the test satellite moves, the satellite channel covering the user terminal is changed from one satellite to another satellite, causing the user link to switch between different test satellites, i.e., the user terminal switches between the coverage areas of different test satellites.

In a feeder link inter-satellite handoff scenario, as the test satellite moves, the satellite channel covering the gateway station is changed from one satellite to another, causing the feeder link to be switched between different satellites, i.e., the gateway station is switched between the coverage areas of different satellites.

In the switching scene between the feeder link and the gateway stations, the test satellite enters the service range of one gateway station into the service range of another gateway station from the service range of one gateway station in the moving process. During this process, the feeder link is switched between the stations.

Referring to fig. 1, the embodiment of the present disclosure provides a system for testing the performance of a satellite communication system, which includes a test satellite 101, a user terminal 102, a gateway station 103, a user link channel simulation and switching device 104, and a feeder link channel simulation and switching device 105. The test satellite 101 is provided with a plurality of satellite channels. The user terminal 102 is operable to generate a reverse link signal and transmit the reverse link signal to the gateway station 103 via the satellite channel of the test satellite. The gateway station 103 is configured to generate a forward link signal and transmit the forward link signal to the user terminal 102 through a satellite channel of the test satellite; the gateway station 103 is provided with a plurality of gateway station channels. One end of the user link channel simulation and switching device 104 is connected with a user terminal, and the other end of the user link channel simulation and switching device 104 is connected with a test satellite; the user link channel simulation and switching device is used for simulating and testing channel changes caused by the movement of the satellite and the user terminal and switching the satellite channel. One end of the feeder link channel simulation and switching device 105 is connected with the gateway station, and the other end of the feeder link channel simulation and switching device 105 is connected with the test satellite; the feeder link channel simulation and switching device is used for simulating channel change caused by movement of a test satellite and switching satellite channels and/or gateway station channels.

By adopting the system for testing the performance of the satellite communication system, the satellite communication system is established by the testing satellite, the user terminal and the gateway station, signal transmission is carried out between the user terminal and the gateway station through the satellite channel, the satellite channel is switched by arranging the user link channel simulation and switching device between the testing satellite and the user terminal, and the satellite channel and/or the gateway station channel is switched by arranging the feed link channel simulation and switching device between the testing satellite and the gateway station so as to simulate the change of the satellite channel and the gateway station channel when the testing satellite moves, thereby realizing the test of the management performance of the mobility of the satellite communication system.

In some embodiments, the user terminal has service functions of terminal voice, internet access and the like; the user terminal supports the functions of satellite beam searching and tracking, and supports the functions of beam switching, satellite switching and gateway station switching.

In some embodiments, the test satellite has multiple beams, the area covered by the beams moving with the motion of the satellite, and the user terminal switches from one beam to another.

In some embodiments, the gateway station has functions of transceiving, modulating and demodulating, signaling, and processing service protocols of feeder link signals, and not only has concurrent access and processing capabilities of multi-user terminals, but also has mobility management capabilities.

In some embodiments, the user link channel simulation and switching device or the feeder link channel simulation and switching device can realize multiple signal paths for realizing path switching of multiple scenes. The user link channel simulation and switching device is used for switching the user terminal between different test satellites or different satellite channels of the same test satellite. The feeder link channel simulation and switching device is used for realizing inter-satellite switching of the feeder link and inter-station switching of the feeder link.

Optionally, the connection material between the test satellite, the user terminal, the gateway station, the user link channel simulation and switching device and the feeder link channel simulation and switching device is a radio frequency cable.

As shown in connection with fig. 2, optionally, the test satellite includes a first satellite load 1011 and a second satellite load 1012; the first satellite load 1011 is provided with a first satellite channel and a second satellite channel, the second satellite load 1012 is provided with a third satellite channel, and the first satellite channel and the second satellite channel are different beam channels of the first satellite load. The user link channel simulation and switching device comprises a user link channel simulator 1041, a first power control module 1042 and a first switching module 1043; the first power control module is used for controlling the power of the channel; the user terminal 102 is connected to the user link channel simulator 1041 sequentially through the first power control module 1042 and the first switching module 1043; the user link channel simulator 1041 communicates the first satellite channel and the second satellite channel of the first satellite load 1011; the user link channel simulator 1041 also communicates with a third satellite channel of the second satellite payload 1012.

Optionally, the first satellite payload 1011 is provided with a fourth satellite channel and the second satellite payload 1012 is provided with a fifth satellite channel; the gateway station 103 includes a first sub-gateway station 1031 and a second sub-gateway station 1032, the first sub-gateway station 1031 being provided with a first gateway station channel, the second sub-gateway station 1032 being provided with a second gateway station channel; the feeder link channel simulation and switching device comprises a feeder link simulator 1051, a second power control module 1052 and a second switching module 1053; the second power control module is used for controlling the power of the channel; the second power control module 1052 is connected to the feeder link simulator 1051 through the second switching module 1053, and the feeder link simulator 1051 is connected to the fourth satellite channel of the first satellite load 1011; the feeder link simulator 1051 also communicates with a fifth satellite channel of the second satellite payload 1012; the second power control module 1052 is in communication with a first gateway station channel of the first sub-gateway station 1031, and the second power control module 1052 is also in communication with a second gateway station channel of the second sub-gateway station 1032.

A satellite communication system is formed by a user terminal, a first satellite load, a second satellite load, a first sub-gateway station and a second sub-gateway station. The user link channel simulator is used for simulating a satellite-ground channel link environment between the user terminal and the first satellite load and the second satellite load, testing channel real-time change caused by high-speed movement of the satellite, and simulating movement of the user terminal. The feeder link channel simulator is used for simulating satellite-ground channel link environments among the first satellite load, the second satellite load, the first sub-gateway station and the second sub-gateway station and testing channel real-time change caused by high-speed movement of the satellite. The user link channel simulation and switching device is used for realizing user link beam switching and inter-satellite switching. The channel simulation and switching device of the feed link is used for realizing inter-satellite switching and inter-gateway switching of the feed link.

Optionally, the user link channel simulator is configured to simulate channel parameters of each channel between the user terminal and the test satellite. Optionally, the feeder link channel simulator is adapted to simulate channel parameters of channels between the gateway station and the test satellite. Optionally, the channel parameters include channel characteristics and environmental parameters; the channel characteristics include one or more of propagation delay, delay variation rate, doppler frequency shift, doppler code offset, free space loss, atmospheric absorption, cloud and rain fading, multipath fading, and the like, and the environmental parameters include one or more of track height, carrier frequency band, beam characteristics, weather, geographical environment, and the like. Optionally, by loading the satellite ephemeris information in the user link channel simulator or the feeder link channel simulator, the motion of multiple satellites can be simulated, and the system mobility management performance verification in the high-speed motion state of the satellites can be carried out. For example, ephemeris information for the first satellite payload and the second satellite payload is loaded within a user link channel simulator or a feeder link channel simulator to simulate movement of the first satellite payload and the second satellite payload.

As shown in fig. 3-1, optionally, the first power control module 1042 is a first attenuator, the first switching module is a first switch 10431, and the ue 102 is connected to the ue channel simulator 1041 sequentially through the first power control module 1042 and the first switch 10431; the user link channel simulator 1041 communicates the first satellite channel and the second satellite channel of the first satellite load 1011; the user link channel simulator 1041 also communicates with a third satellite channel of the second satellite payload 1012. The user link channel simulation and switching device switches among the first satellite channel, the second satellite channel, and the third satellite channel through the first switch 10431.

Therefore, the switching among a plurality of user links can be realized by switching on and off the first selector switch. Meanwhile, the first attenuator can ensure that the link power is in a controllable range.

In some embodiments, to facilitate switching, a programmable switch controlled by software is typically used as the first switch. In some embodiments, switching of the communication channel of the user link is performed by a software controlled programmable switch.

In some embodiments, in a user link intra-satellite beam switching scenario, the first switch is first in channel 1 connectivity and the user terminal is connected to a first satellite channel of a first satellite payload. Subsequently, the channel 2 of the first switch is set to be connected, and the user terminal is switched to the second satellite channel of the first satellite load.

In some embodiments, in a user link inter-satellite handoff scenario, the first switch is first in lane 1 connectivity and the user terminal is connected to the first satellite payload. Subsequently, the channel 3 of the first switch is set to be connected and the user terminal is switched to the second satellite load.

Referring to fig. 3-2, optionally, the first power control module 1042 is a first attenuator, the first switching module is a first power divider 10432, and the ue 102 is connected to the user link channel simulator 1041 sequentially through the first power control module 1042 and the first power divider 10432; the user link channel simulator 1041 communicates the first satellite channel and the second satellite channel of the first satellite load 1011; the user link channel simulator 1041 also communicates with a third satellite channel of the second satellite payload 1012. The user link channel simulation and switching device adjusts the signal strength of the first satellite channel, the second satellite channel and the third satellite channel through the user link channel simulator so as to switch among the first satellite channel, the second satellite channel and the third satellite channel. The first power divider can combine and connect a plurality of downlink signal paths of different satellite loads and different satellite channels of the same satellite load to the user terminal, and can divide uplink signals of the user terminal into multiple paths to be connected to different satellite channels of different satellite loads and the same satellite load. Meanwhile, the first attenuator can ensure that the link power is in a controllable range.

In some embodiments, in a user link intra-satellite beam switching scenario, two channels 1-2, 1-3 connect a first satellite channel and a second satellite channel of a first satellite payload, respectively. As the beam signal of one satellite channel becomes stronger and the beam signal of the other satellite channel becomes weaker, the user terminal switches between the two satellite channels of the first satellite payload. In the process, the 1-4 channels are connected with the second satellite load, and the second satellite load does not transmit signals, so that the test is not influenced.

In some embodiments, in a user link inter-satellite handoff scenario, two channels 1-2 and 1-4 connect a first satellite channel of a first satellite load and a third satellite channel of a second satellite load, respectively. As the signal of one satellite payload becomes stronger and the signal of the other satellite payload becomes weaker, the user terminal switches between the first satellite channel and the third satellite channel. In this process, the 1-3 channels connect to the second satellite channel of the first satellite payload, and since this beam does not transmit a signal, it does not affect the test.

As shown in connection with fig. 4-1, optionally, the second power control module includes a second attenuator 10521 and a third attenuator 10522; the second switching module includes a second switch 10531 and a third switch 10532; the second attenuator 10521 is connected to the feeder link channel simulator 1051 sequentially through the third switch 10532 and the second switch 10531; the third attenuator 10522 is connected to the feeder link channel simulator 1051 sequentially through the third switch 10532 and the second switch 10531; the feeder link channel simulator 1051 is in communication with a fourth satellite channel of the first satellite load 1011, and the feeder link channel simulator 1051 is also in communication with a fifth satellite channel of the second satellite load 1012; the second attenuator 10521 communicates with a first station channel of the first sub-station 1031, and the third attenuator 10522 communicates with a second station channel of the second sub-station 1032; the feeder link channel simulation and switching device switches between the fourth satellite channel and the fifth satellite channel through the second switch 10531; the feeder link channel simulation and switching device switches between the first gateway station channel and the second gateway station channel through the third switch 10532. Therefore, the two-stage switch is used in the feeder link channel simulation and switching device, and the switching between the first satellite load and the second satellite load and the switching between the first sub-gateway station and the second sub-gateway station can be realized by switching on and off the switch. Meanwhile, the signal power of the channel of the feeder link is ensured to be in a controllable range by arranging the second attenuator and the third attenuator.

In some embodiments, to facilitate switching, a programmable switch controlled by software is typically used as the first switch. In some embodiments, switching of the communication channel of the feeder link is performed by a software controlled programmable switch.

In some embodiments, in a feeder link inter-satellite switching scenario, the second switch is first set to channel 1 connectivity and the third switch is set to channel 3 connectivity, such that the first satellite load is connected to the first sub-gateway station. Subsequently, a second diverter switch is set in communication on lane 2 so that the second satellite load is connected to the first sub-gateway station.

In some embodiments, in a handoff scenario between feeder link gateway stations, the second switch is set to pass through channel 1 and the third switch is set to pass through channel 3, such that the first satellite load is connected to the first sub-gateway station. Subsequently, a third diverter switch is set in communication on the channel 4, so that the first satellite load is connected to the second sub-gateway station.

As shown in connection with fig. 4-2, optionally, the second power control module includes a second attenuator 10521 and a third attenuator 10522; the second switching module includes a second power divider 10533 and a third power divider 10534; the second attenuator 10521 is connected to the feeder link channel simulator 1051 sequentially through the third power divider 10534 and the second power divider 10533; the third attenuator 10522 is connected to the feeder link channel simulator 1051 sequentially through the third power divider 10534 and the second power divider 10533; the feeder link channel simulator 1051 is in communication with a fourth satellite channel of the first satellite load 1011, and the feeder link channel simulator 1051 is also in communication with a fifth satellite channel of the second satellite load 1012; the second attenuator 10521 communicates with a first station channel of the first sub-station 1031, and the third attenuator 10522 communicates with a second station channel of the second sub-station 1032; the feed link channel simulation and switching device adjusts the signal strength of the fourth satellite channel and the signal strength of the fifth satellite channel through the feed link channel simulator so as to switch the fourth satellite channel and the fifth satellite channel; the feeder link channel simulator and switching device adjusts the signal strength of the first and second station channels via the feeder link channel simulator to effect switching between the first and second station channels. Therefore, two stages of power dividers are used in the feeder link channel simulation and switching device, the second power divider and the third power divider are connected in series, signals of the first satellite load and the second satellite load can be merged and sent to the gateway station, and meanwhile, forward link signals of the first sub-gateway station and the second sub-gateway station can be divided into multiple paths and connected to the first satellite load and the second satellite load. Meanwhile, the signal power of the channel of the feeder link is ensured to be in a controllable range by arranging the second attenuator and the third attenuator.

In some embodiments, in a feed link inter-satellite switching scenario, signals of a first satellite load and a second satellite load after passing through a feed link channel simulator are combined by two paths 1-3 and 2-3, and the combined signals are transmitted to a first sub-gateway station through a path 4-5. The first sub-gateway station switches between the first satellite load and the second satellite load as the signal of one satellite load becomes stronger and the signal of the other satellite load becomes weaker. In this process, the second sub-gateway station is in an inactive state.

In some embodiments, in a handoff scenario between feeder link gateway stations, signals of the first satellite payload travel through 1-3 paths to the third power splitter and through 4-5 paths to the first sub-gateway station. The first satellite payload is switched between the first sub-gateway station and the second sub-gateway station as the signal of one gateway station channel becomes stronger and the signal of the other gateway station channel becomes weaker. During this process, the second satellite payload is in an inactive state.

As shown in fig. 5, an embodiment of the present disclosure provides a method for testing performance of a satellite communication system, where the method is implemented based on the system for testing performance of a satellite communication system, and the method includes:

step S501, communication channel switching is carried out in the process of satellite communication between a user terminal and a gateway station;

step S502, acquiring the sending signal and the receiving signal of the user terminal and the gateway station under different communication channel states;

step S503, carrying out signal analysis on the sending signal and the receiving signal to obtain an analysis result;

and step S504, obtaining a test result according to the analysis result.

By adopting the method for testing the performance of the satellite communication system provided by the embodiment of the disclosure, the communication channel is switched in the process of satellite communication between the user terminal and the gateway station, the sending signal and the receiving signal of the user terminal and the gateway station in different communication channel states are obtained, the sending signal and the receiving signal are subjected to signal analysis, and the test result is obtained according to the obtained analysis result. Therefore, the communication channel switching is carried out in the process of satellite communication between the user terminal and the gateway station so as to simulate the change of the satellite channel and the gateway station channel when the test satellite moves, the sending signals and the receiving signals of the user terminal and the gateway station in different communication channel states are obtained, the analysis result is obtained according to the sending signals and the receiving signals, and the test result is obtained according to the analysis result, so that the test on the management performance of the satellite communication system mobility can be realized. In addition, different satellite communication scenes such as voice, data, the Internet of things and the like can be established through the satellite communication system, different protocol flows such as registration, activation, paging, random access and the like are simulated in different scenes, system performance in the flows is verified, and the test application range of the satellite communication system is expanded.

Optionally, the analysis result includes one or more of a signal transmission rate, a signal quality, a signal delay, a handover request delay, a number of covered users, a scene handover success rate, and the like.

Optionally, obtaining a test result according to the analysis result includes: matching a test result corresponding to the analysis result in a preset test result database; the corresponding relation between the analysis result and the test result is stored in the test result database.

Optionally, in a case where the user terminal is used as the sending end, the gateway station is used as the receiving end; the user terminal generates a sending signal and sends the sending signal to the gateway station through the test satellite; the gateway station takes the received signal as a received signal.

Optionally, in a case where the gateway station is used as a sending end, the user terminal is a receiving end; the gateway station generates a sending signal and sends the sending signal to the user terminal through the test satellite; the user terminal takes the received signal as a received signal.

Optionally, in a case that the first switching module is a first switch, performing communication channel switching in a process of performing satellite communication between the user terminal and the gateway station includes: during satellite communication between the user terminal and the gateway station, the communication channel of the user link is switched by the first switch.

In some embodiments, to facilitate switching, a programmable switch controlled by software is typically used as the first switch. In some embodiments, switching of the communication channel of the user link is performed by a software controlled programmable switch.

Optionally, the switching of the communication channel of the user link by the first switch includes: switching a communication channel of a user link to a first satellite channel through a first switch; and after a preset time period, switching the first satellite channel to the second satellite channel through the first switch. Therefore, the first satellite channel and the second satellite channel are different beam channels of the first satellite load, the first satellite channel is switched to the second satellite channel through the first switch to test the intra-satellite beam switching of the user link, the sending signal and the receiving signal are further obtained, the analysis result of the sending signal and the receiving signal is obtained, the test result is obtained according to the analysis result, and therefore the test on the management performance of the mobility of the satellite communication system can be achieved.

Optionally, the switching of the communication channel of the user link by the first switch includes: switching a communication channel of a user link to a first satellite channel through a first switch; and after a preset time period, switching the first satellite channel to a third satellite channel through a first switch. Therefore, the first satellite channel and the third satellite channel are channels with different satellite loads, the first satellite channel is switched to the third satellite channel through the first selector switch to test the inter-satellite switching of the user link, the sending signal and the receiving signal are further obtained, the analysis result of the sending signal and the receiving signal is obtained, the test result is obtained according to the analysis result, and therefore the test on the mobility management performance of the satellite communication system can be achieved.

Optionally, in a case that the first switching module is a first power divider, performing communication channel switching during satellite communication between the user terminal and the gateway station includes: during the satellite communication between the user terminal and the gateway station, the communication channel of the user link is switched by the user link channel simulator.

Optionally, the switching of the communication channel of the user link by the user link channel simulator includes: adjusting the signal intensity of a first satellite channel, a second satellite channel and a third satellite channel through a user link channel simulator according to a first preset rule so as to switch a communication channel of a user link to the first satellite channel; after a preset time period, the signal intensity of the first satellite channel, the signal intensity of the second satellite channel and the signal intensity of the third satellite channel are adjusted through the user link channel simulator according to a second preset rule, so that the first satellite channel is switched to the second satellite channel. Therefore, the first satellite channel and the second satellite channel are different beam channels of the first satellite load, the first satellite channel is switched to the second satellite channel through the user link channel simulator to test the intra-satellite beam switching of the user link, the transmitting signal and the receiving signal are further obtained, the analysis result of the transmitting signal and the receiving signal is obtained, the test result is obtained according to the analysis result, and therefore the test on the management performance of the mobility of the satellite communication system can be achieved.

Optionally, the first preset rule is a ratio of signal strengths among the first satellite channel, the second satellite channel and the third satellite channel, wherein the signal strength of the first satellite channel is greater than the signal strength of the second satellite channel and the signal strength of the first satellite channel is greater than the signal strength of the third satellite channel. Optionally, the first preset rule is generated according to a specific satellite orbit and a constellation configuration.

Optionally, the second preset rule is a ratio of signal strengths among the first satellite channel, the second satellite channel and the third satellite channel, wherein the signal strength of the second satellite channel is greater than the signal strength of the first satellite channel and the signal strength of the second satellite channel is greater than the signal strength of the third satellite channel. Optionally, the second preset rule is generated according to a specific satellite orbit and constellation configuration.

Optionally, the switching of the communication channel of the user link by the user link channel simulator includes: adjusting the signal intensity of a first satellite channel, a second satellite channel and a third satellite channel through a user link channel simulator according to a first preset rule so as to switch a communication channel of a user link to the first satellite channel; after a preset time period, the signal strength of the first satellite channel, the signal strength of the second satellite channel and the signal strength of the third satellite channel are adjusted through the user link channel simulator according to a third preset rule, so that the first satellite channel is switched to the third satellite channel. Therefore, the first satellite channel and the third satellite channel are channels with different satellite loads, the first satellite channel is switched to the third satellite channel through the user link channel simulator to test the inter-satellite switching of the user link, the sending signal and the receiving signal are further obtained, the analysis result of the sending signal and the receiving signal is obtained, the test result is obtained according to the analysis result, and therefore the test on the management performance of the satellite communication system mobility can be achieved.

Optionally, the third preset rule is a ratio of signal strengths among the first satellite channel, the second satellite channel and a third satellite channel, wherein the signal strength of the third satellite channel is greater than the signal strength of the first satellite channel and the signal strength of the third satellite channel is greater than the signal strength of the second satellite channel. Optionally, the third preset rule is generated according to a specific satellite orbit and constellation configuration.

Optionally, in a case where the second switching module includes a second switch and a third switch, performing communication channel switching during satellite communication between the user terminal and the gateway station includes: and in the process of satellite communication between the user terminal and the gateway station, switching the communication channel of the feeder link through the second switch or the third switch.

In some embodiments, to facilitate switching, programmable switches controlled by software are typically used as the second and third switches. In some embodiments, switching of the communication channel of the feeder link is performed by a software controlled programmable switch.

Optionally, the switching of the communication channel of the feeder link by the second switch or the third switch includes: switching the communication channel of the feeder link to a fourth satellite channel through a second switch, and switching the communication channel of the feeder link to a first gateway station channel through a third switch; and after the preset time period, switching the fourth satellite channel to the fifth satellite channel through the second selector switch. Therefore, the fourth satellite channel and the fifth satellite channel are channels with different satellite loads, the fourth satellite channel is switched to the fifth satellite channel through the second selector switch to test the inter-satellite switching of the feed link, the sending signal and the receiving signal are further obtained, the analysis result of the sending signal and the receiving signal is obtained, the test result is obtained according to the analysis result, and therefore the test on the management performance of the satellite communication system mobility can be achieved.

Optionally, the switching of the communication channel of the feeder link by the second switch or the third switch includes: switching the communication channel of the feeder link to a fourth satellite channel through a second switch, and switching the communication channel of the feeder link to a first gateway station channel through a third switch; and after the preset time period, switching the first gateway station channel to the second gateway station channel through a third switch. Therefore, the first gateway station channel and the second gateway station channel are channels of different sub-gateway stations, the first gateway station channel is switched to the second gateway station channel through the second switch to test switching among the gateway stations of the feeder link, the sending signal and the receiving signal are obtained, the analysis result of the sending signal and the receiving signal is obtained, the test result is obtained according to the analysis result, and therefore the test of the management performance of the mobility of the satellite communication system can be achieved.

Optionally, in a case where the first switching module includes the second power divider and the third power divider, performing communication channel switching during satellite communication between the user terminal and the gateway station includes: during satellite communication between the user terminal and the gateway station, communication channel switching of the feeder link is performed by the feeder link channel simulator.

Optionally, the communication channel switching of the feeder link is performed by a feeder link channel simulator, including: adjusting the signal intensity of a fourth satellite channel, a fifth satellite channel, a first gateway station channel and a second gateway station channel according to a fourth preset rule through a feeder link channel simulation and switching device so as to switch a communication channel of a feeder link to the fourth satellite channel and the first gateway station channel; after a preset time period, the signal strength of the fourth satellite channel and the signal strength of the fifth satellite channel are adjusted through the feeder link channel simulation and switching device according to a fifth preset rule, so that the fourth satellite channel is switched to the fifth satellite channel. Therefore, the fourth satellite channel and the fifth satellite channel are channels with different satellite loads, the fourth satellite channel is switched to the fifth satellite channel through the feeder link channel simulator to test the inter-satellite switching of the feeder link, the sending signal and the receiving signal are further obtained, the analysis result of the sending signal and the receiving signal is obtained, the test result is obtained according to the analysis result, and therefore the test on the management performance of the satellite communication system mobility can be achieved.

Optionally, the fourth preset rule includes a ratio of signal strengths between a fourth satellite channel and a fifth satellite channel, and a ratio of signal strengths between the first gateway station channel and the second gateway station channel, wherein the signal strength of the fourth satellite channel is greater than the signal strength of the fifth satellite channel and the signal strength of the first gateway station channel is greater than the signal strength of the second gateway station channel. Optionally, the fourth preset rule is generated according to a specific satellite orbit and constellation configuration.

Optionally, the fifth preset rule includes a ratio of signal strengths between the fourth satellite channel and a fifth satellite channel, wherein the signal strength of the fifth satellite channel is greater than the signal strength of the fourth satellite channel. Optionally, the fifth preset rule is generated according to a specific satellite orbit and constellation configuration.

Optionally, the communication channel switching of the feeder link is performed by a feeder link channel simulator, including: adjusting the signal intensity of a fourth satellite channel, a fifth satellite channel, a first gateway station channel and a second gateway station channel according to a fourth preset rule through a feeder link channel simulation and switching device so as to switch a communication channel of a feeder link to the fourth satellite channel and the first gateway station channel; after the preset time period, the signal strength of the first gateway station channel and the second gateway station channel is adjusted through the feeder link channel simulation and switching device according to a sixth preset rule so as to switch the first gateway station channel to the second gateway station channel. Therefore, the first gateway station channel and the second gateway station channel are channels of different sub-gateway stations, the first gateway station channel is switched to the second gateway station channel through the feeder link channel simulator to test switching among the gateway stations of the feeder link, then the sending signal and the receiving signal are obtained, the analysis result of the sending signal and the receiving signal is obtained, the test result is obtained according to the analysis result, and therefore the test of the management performance of the mobility of the satellite communication system can be achieved.

Optionally, the sixth preset rule comprises a ratio of signal strengths between the first and second gateway station channels, wherein the signal strength of the second gateway station channel is greater than the signal strength of the first gateway station channel. Optionally, the sixth preset rule is generated according to a specific satellite orbit and constellation configuration.

Since the satellite communication system, especially the medium and low orbit satellite communication system, has very typical network characteristics, the verification of the performance of the satellite communication system must be carried out in a corresponding network environment. The influence factors of the network environment are very many, such as the large transmission delay of the satellite, the transmission delay is very large because the orbital height of the satellite is basically more than 500km, the round-trip delay of the satellite is 6.7ms and the round-trip delay of the beam edge can reach more than 7.2ms according to the orbital height of 1000km and the plus or minus 22 degrees of the satellite beam angle, when the information result is transmitted back to the user, the channel information is changed because of the larger delay, and the user can even miss the SSB/CSI-RS measurement window because of the large delay; for example, when the satellite height is high or the beam angle is large, the range of a tracking area is large, the single beam covers 808km in diameter, the coverage range can reach 512498 square kilometers, so that the number of users under a single satellite is large, the number of users under a single tracking area is large, the signaling overhead of paging is greatly increased, the coverage area of a single satellite is large, the number of switched users is large in unit time, the signaling overhead is large, service continuity is difficult to guarantee, according to the measurement and calculation of 3GPP, when the coverage range of a single satellite of a low-orbit satellite is 26000km2, 14893 users are switched into the satellite, therefore, for the single satellite, the number of switched users is 29786 within a few minutes when the satellite passes through a ground coverage cell, which brings huge signaling overhead and causes signaling storm; as another example, the flight speed of the satellite is 7.56km/s, which is equivalent to 27216km/h, and is about 30 times of the flight speed of the airplane. According to the official data of space x in the united states, the low orbit broadband satellite over-time in the Starlink constellation is 4.1 min. This means that the user will complete a handover at 4.1min at the longest.

According to the method for testing the performance of the satellite communication system, the communication channel is switched in the process of satellite communication between the user terminal and the gateway station, the sending signal and the receiving signal of the user terminal and the gateway station in different communication channel states are obtained, signal analysis is carried out on the sending signal and the receiving signal, and the test result is obtained according to the obtained analysis result. Therefore, the communication channel switching is carried out in the process of satellite communication between the user terminal and the gateway station so as to simulate the change of the satellite channel and the gateway station channel when the test satellite moves, the sending signals and the receiving signals of the user terminal and the gateway station in different communication channel states are obtained, the analysis result is obtained according to the sending signals and the receiving signals, and the test result is obtained according to the analysis result, so that the test on the management performance of the satellite communication system mobility can be realized.

As shown in fig. 6, an apparatus for testing performance of a satellite communication system according to an embodiment of the present disclosure includes a processor (processor)600 and a memory (memory) 601. Optionally, the apparatus may also include a Communication Interface 602 and a bus 603. The processor 600, the communication interface 602, and the memory 601 may communicate with each other via a bus 603. The communication interface 602 may be used for information transfer. The processor 600 may invoke logic instructions in the memory 601 to perform the method for testing the performance of a satellite communication system of the above-described embodiments.

In addition, the logic instructions in the memory 601 may be implemented in the form of software functional units and stored in a computer readable storage medium when the logic instructions are sold or used as independent products.

The memory 601 is a computer-readable storage medium, and can be used for storing software programs, computer-executable programs, such as program instructions/modules corresponding to the methods in the embodiments of the present disclosure. The processor 600 executes functional applications and data processing by executing program instructions/modules stored in the memory 601, i.e., implements the method for testing the performance of the satellite communication system in the above-described embodiments.

The memory 601 may include a storage program area and a storage data area, wherein the storage program area may store an operating system, an application program required for at least one function; the storage data area may store data created according to the use of the terminal device, and the like. In addition, the memory 601 may include a high speed random access memory, and may also include a non-volatile memory.

By adopting the device for testing the performance of the satellite communication system provided by the embodiment of the disclosure, the communication channel is switched in the process of satellite communication between the user terminal and the gateway station, the sending signal and the receiving signal of the user terminal and the gateway station in different communication channel states are obtained, the sending signal and the receiving signal are subjected to signal analysis, and the test result is obtained according to the obtained analysis result. Therefore, the communication channel switching is carried out in the process of satellite communication between the user terminal and the gateway station so as to simulate the change of the satellite channel and the gateway station channel when the test satellite moves, the sending signals and the receiving signals of the user terminal and the gateway station in different communication channel states are obtained, the analysis result is obtained according to the sending signals and the receiving signals, and the test result is obtained according to the analysis result, so that the test on the management performance of the satellite communication system mobility can be realized.

The embodiment of the disclosure provides an electronic device, which comprises the device for testing the performance of the satellite communication system. Optionally, the electronic device comprises a computer, a server, or the like. The electronic equipment switches communication channels in the process of satellite communication between the user terminal and the gateway station, acquires sending signals and receiving signals of the user terminal and the gateway station in different communication channel states, performs signal analysis on the sending signals and the receiving signals, and acquires a test result according to an acquired analysis result. Therefore, the communication channel switching is carried out in the process of satellite communication between the user terminal and the gateway station so as to simulate the change of the satellite channel and the gateway station channel when the test satellite moves, the sending signals and the receiving signals of the user terminal and the gateway station in different communication channel states are obtained, the analysis result is obtained according to the sending signals and the receiving signals, and the test result is obtained according to the analysis result, so that the test on the management performance of the satellite communication system mobility can be realized.

Embodiments of the present disclosure provide a readable storage medium having stored thereon computer-executable instructions configured to perform the above-described method for testing performance of a satellite communication system.

Embodiments of the present disclosure provide a computer program product comprising a computer program stored on a computer readable storage medium, the computer program comprising program instructions which, when executed by a computer, cause the computer to perform the above-described method for testing the performance of a satellite communication system.

The readable storage medium described above may be a transitory computer readable storage medium or a non-transitory computer readable storage medium.

The above description and drawings sufficiently illustrate embodiments of the disclosure to enable those skilled in the art to practice them. Other embodiments may incorporate structural, logical, electrical, process, and other changes. The examples merely typify possible variations. Individual components and functions are optional unless explicitly required, and the sequence of operations may vary. Portions and features of some embodiments may be included in or substituted for those of others. Furthermore, the words used in the specification are words of description only and are not intended to limit the claims. As used in the description of the embodiments and the claims, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. Similarly, the term "and/or" as used in this application is meant to encompass any and all possible combinations of one or more of the associated listed. Furthermore, the terms "comprises" and/or "comprising," when used in this application, specify the presence of stated features, integers, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, integers, steps, operations, elements, components, and/or groups thereof. Without further limitation, an element defined by the phrase "comprising an …" does not exclude the presence of other like elements in a process, method or apparatus that comprises the element. In this document, each embodiment may be described with emphasis on differences from other embodiments, and the same and similar parts between the respective embodiments may be referred to each other. For methods, products, etc. of the embodiment disclosures, reference may be made to the description of the method section for relevance if it corresponds to the method section of the embodiment disclosure.

Those of skill in the art would appreciate that the various illustrative elements and algorithm steps described in connection with the embodiments disclosed herein may be implemented as electronic hardware or combinations of computer software and electronic hardware. Whether such functionality is implemented as hardware or software may depend upon the particular application and design constraints imposed on the solution. Skilled artisans may implement the described functionality in varying ways for each particular application, but such implementation decisions should not be interpreted as causing a departure from the scope of the disclosed embodiments. It can be clearly understood by the skilled person that, for convenience and brevity of description, the specific working processes of the system, the apparatus and the unit described above may refer to the corresponding processes in the foregoing method embodiments, and are not described herein again.

In the embodiments disclosed herein, the disclosed methods, products (including but not limited to devices, apparatuses, etc.) may be implemented in other ways. For example, the above-described apparatus embodiments are merely illustrative, and for example, the division of the units may be merely a logical division, and in actual implementation, there may be another division, for example, multiple units or components may be combined or integrated into another system, or some features may be omitted, or not executed. In addition, the shown or discussed mutual coupling or direct coupling or communication connection may be an indirect coupling or communication connection through some interfaces, devices or units, and may be in an electrical, mechanical or other form. The units described as separate parts may or may not be physically separate, and parts displayed as units may or may not be physical units, may be located in one place, or may be distributed on a plurality of network units. Some or all of the units can be selected according to actual needs to implement the present embodiment. In addition, functional units in the embodiments of the present disclosure may be integrated into one processing unit, or each unit may exist alone physically, or two or more units are integrated into one unit.

The flowchart and block diagrams in the figures illustrate the architecture, functionality, and operation of possible implementations of systems, methods and computer program products according to embodiments of the present disclosure. In this regard, each block in the flowchart or block diagrams may represent a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). In some alternative implementations, the functions noted in the block may occur out of the order noted in the figures. For example, two blocks shown in succession may, in fact, be executed substantially concurrently, or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved. In the description corresponding to the flowcharts and block diagrams in the figures, operations or steps corresponding to different blocks may also occur in different orders than disclosed in the description, and sometimes there is no specific order between the different operations or steps. For example, two sequential operations or steps may in fact be executed substantially concurrently, or they may sometimes be executed in the reverse order, depending upon the functionality involved. Each block of the block diagrams and/or flowchart illustrations, and combinations of blocks in the block diagrams and/or flowchart illustrations, can be implemented by special purpose hardware-based systems that perform the specified functions or acts, or combinations of special purpose hardware and computer instructions.