A highly reliable communication system based on autonomous care

Abstract

The present invention discloses a highly reliable communication system based on autonomous care. This system includes transceiver A and transceiver B. Transceiver A includes a data management module, a radio frequency receiving module, a process start determination module, a link status evaluation module, a model matching module, and a radio frequency transmitting module. Transceiver B includes a radio frequency transmitting module, a data management module, and a radio frequency receiving module. By using the present invention, in deep space exploration activities such as on Mars, extreme weather such as Martian sandstorms can be identified through the quality of the communication link, the severity of the impact of extreme weather on the communication channel can be evaluated according to the method of model matching, and relevant measures can be taken according to the severity level, thus maximizing the safety of the detector and high-reliability signal transmission.

Description

Technical Field

[0001] The present invention discloses a highly reliable communication system based on autonomous caretaking, which belongs to the field of deep space exploration relay communication. Background Art

[0002] In a Mars exploration mission, due to the long communication distance, there is a large time delay for ground remote control instructions (the maximum distance between the Earth and Mars is 400 million kilometers, and the one-way light travel time is 22 minutes). Moreover, because the visible arc time with the Earth is limited, real-time control is not possible. Therefore, it mainly relies on autonomous communication between the orbiter and the lander / rover. However, due to the special geographical environment on the surface of Mars, compared with other deep space exploration missions, it has its particularity. The sandstorm wind speed on Mars can reach 180 m / s, which is much higher than that of Earth sandstorms. Such large-scale and long-lasting natural disasters will make the channel conditions very complex, posing a great risk to the detector. Traditional communication methods cannot provide early warning information to the detector to ensure its own safety. Summary of the Invention

[0003] The technical problem solved by the present invention is: overcoming the deficiencies of the prior art, a highly reliable communication system based on autonomous caretaking is proposed, which can identify extreme weather such as Mars sandstorms through the quality of the communication link, evaluate the severity of the impact of extreme weather on the communication channel according to the method of model matching, and take relevant measures according to the severity level, maximizing the safety of the detector and high-reliability signal transmission.

[0004] The technical solution of the present invention is: a highly reliable communication system based on autonomous caretaking, including transceiver A and transceiver B. Transceiver A includes a data management module, a radio frequency receiving module, a process start determination module, a link state evaluation module, a model matching module, and a radio frequency transmitting module; transceiver B includes a radio frequency transmitting module, a data management module, and a radio frequency receiving module;

[0005] After transceiver B is powered on, the internal radio frequency transmitting module receives the SDU data frame from the data management module, modulates it into a radio frequency signal and sends it to transceiver A. After the radio frequency receiving module inside transceiver A receives the radio frequency signal, it demodulates the SDU data frame and sends it to the data management module, and at the same time smooths the signal-to-noise ratio at intervals of T_delta and outputs it to the process start determination module;

[0006] The process start determination module compares the input signal-to-noise ratio with the internal start threshold. When M consecutive input signal-to-noise ratios are less than the start threshold, the autonomous caretaking process starts. The process start determination module then records the star time scale of the input signal-to-noise ratio, and outputs the signal-to-noise ratio and its corresponding star time scale obtained from the radio frequency receiving module to the link state evaluation module;

[0007] After the link state assessment module detects an SNR input, it randomly starts with a certain input SNR and records the subsequent M input SNRs and their ephemeris time stamps. It then obtains the SNR mean and amplitude within this period based on the link assessment algorithm and outputs the SNR mean, amplitude, first frame SNR time stamp, and last frame SNR time stamp to the model matching module.

[0008] After the model matching module receives the mean SNR, amplitude, first frame SNR time stamp and last frame SNR time stamp, it first retrieves the theoretical SNR value of the corresponding arc segment from the local database based on the first frame SNR time stamp and the last frame SNR time stamp, and calculates the theoretical SNR mean and amplitude; secondly, the degree of impact on the communication link is obtained according to the model matching algorithm; if the degree of impact on the communication link is mild, the model matching module feeds back the current state to the data control module through telemetry, and sends an initialization instruction to the process start judgment module, and then ends the autonomous care process; if the degree of impact on the communication link is moderate, the model matching module first generates an SPDU control frame and outputs it to the RF transmission module, which then sends the SPD The U control frame is modulated into an RF signal and sent to transceiver B. After receiving the RF signal, the RF receiving module of transceiver B demodulates the SPDU control frame and sends it to the digital control module. After the digital control module verifies the SPDU control frame, it sets the parameters of the RF transmitting module to the call channel mode through remote control commands. After the model matching module generates and sends the SPDU control frame, it feeds back the degree of impact on the current communication link to the digital control module through telemetry, and sends a remote control command to the digital control module to shut down the RF transmitting module. If the degree of impact on the communication link is severe, the model matching module feeds back this status to the digital control module through telemetry, and sends a remote control command to the digital control module to shut down the RF transmitting module and the RF receiving module.

[0009] The length of the data field of the SDU control frame is 1-2048 bytes, and the frame format is consistent with the frame format specified in the CCSDS protocol.

[0010] The starting threshold value is the theoretical value of the signal-to-noise ratio of the current arc segment×(1-TH1%); TH1 represents the reduction range of the signal-to-noise ratio under abnormal conditions.

[0011] The ephemeris time mark is the ephemeris time when the process start determination module receives the signal-to-noise ratio.

[0012] The link evaluation algorithm is used to obtain the signal-to-noise ratio mean and amplitude within the current period, including:

[0013]

[0014] Wherein, SNR_M2 represents the value of the M2th input signal-to-noise ratio, and M2 represents the number of input signal-to-noise ratios.

[0015] The degree of influence on the communication link obtained according to the model matching algorithm includes:

[0016] Calculate the evaluation factor β of the degree of influence on the link. If β < η1, the degree of influence on the link is mild. If η1 ≤ β < η2, the degree of influence on the link is moderate. If β ≥ η2, the degree of influence on the link is severe.

[0017]

[0018] Among them, η1 represents the boundary threshold between mild and moderate influences, and η2 represents the boundary threshold between moderate and severe influences.

[0019] The SPDU control frame is used to inform the transceiver of the communication channel, rate, and coding method.

[0020] The call channel mode is Channel 1, 1 kbps, and 1 / 2 rate convolutional coding in the CCSDS Proximity-1 protocol, which is the same as that specified in the CCSDS protocol.

[0021] Compared with the prior art, the present invention has the following beneficial effects:

[0022] (1) Through link state evaluation, the present invention accurately obtains the channel quality of the current link, thereby inversely deducing the severity of extreme weather and providing early warnings for the detector.

[0023] (2) Through the SPDU control frame, the present invention autonomously adjusts the communication mode, ensuring high-reliability signal transmission to the greatest extent.

[0024] (3) The present invention can be applied to deep space exploration represented by Mars, embodying the design concept of system optimization and the highest reliability in deep space exploration missions. Description of the Drawings

[0025] Figure 1 It is a schematic block diagram of a high-reliability communication system based on autonomous care. Detailed Embodiments

[0026] The following further describes the present invention in conjunction with the drawings and specific embodiments.

[0027] The present invention can quickly and accurately evaluate the quality of the current communication link, inversely deduce the severity of extreme weather, ensure the safety of the detector and high-reliability signal transmission to the greatest extent, and optimize the FPGA implementation resources on the basis of being compatible with the CCSDS protocol, embodying the design concept of system optimization and efficiency optimization in deep space exploration missions.

[0028] A highly reliable communication system based on autonomous monitoring, comprising: a transceiver A and a transceiver B. The transceiver A includes a data management module, a radio frequency receiving module, a process start determination module, a link status evaluation module, a model matching module, and a radio frequency transmitting module. The transceiver B includes a radio frequency transmitting module, a data management module, and a radio frequency receiving module.

[0029] After the transceiver B is powered on, its radio frequency transmitting module receives the SDU data frame (Service Data Unit, see the CCSDS protocol) from the data management module, modulates it into a radio frequency signal and sends it to the transceiver A. After the radio frequency receiving module of the transceiver A receives the radio frequency signal, it demodulates the SDU data frame and sends it to the data management module, and at the same time smooths the signal-to-noise ratio at intervals of T_delta and outputs it to the process start determination module. Among them, the value of T_delta should not be too large, generally 10 ms.

[0030] The process start determination module compares the input signal-to-noise ratio with the internal start threshold value. This threshold value is generally the theoretical signal-to-noise ratio value of the current arc segment × (1 - TH1%), where TH1 represents the reduction amplitude of the signal-to-noise ratio in the abnormal state, generally 30%. If 100 consecutive input signal-to-noise ratios are less than the start threshold value, the autonomous monitoring process starts. The process start determination module then records the time when the input signal-to-noise ratio arrives, denoted as the star time scale, and outputs the signal-to-noise ratio and its corresponding star time scale obtained from the radio frequency receiving module to the link status evaluation module.

[0031] After the link status evaluation module detects the input of the signal-to-noise ratio, it randomly starts from a certain input signal-to-noise ratio and records the subsequent 1000 input signal-to-noise ratios and their star time scales, and obtains the mean value and amplitude of the signal-to-noise ratio within this period of time according to the link evaluation algorithm, as follows

[0032]

[0033]

[0034] And outputs the mean value of the signal-to-noise ratio, the amplitude, the time scale of the first-frame signal-to-noise ratio, and the time scale of the last-frame signal-to-noise ratio to the model matching module.

[0035] After receiving the mean value of the signal-to-noise ratio, the amplitude, the time scale of the first-frame signal-to-noise ratio, and the time scale of the last-frame signal-to-noise ratio, the model matching module first retrieves the theoretical signal-to-noise ratio value of the corresponding arc segment from the local database according to the time scale of the first-frame signal-to-noise ratio and the time scale of the last-frame signal-to-noise ratio, and calculates the theoretical mean value and amplitude of the signal-to-noise ratio. Secondly, according to the model matching algorithm, the degree of influence on the communication link is obtained. Specifically, the link influence degree evaluation factor (β) is calculated by the following formula. If β < 0.5, the degree of influence on the link is mild. If 0.5 ≤ β < 1, the degree of influence on the link is moderate. If β ≥ 1, the degree of influence on the link is severe.

[0036]

[0037] If the degree of influence on the communication link is mild, the model matching module feeds back this status to the digital management module through telemetry, and sends an initialization instruction to the process start determination module, and then ends the autonomous care process;

[0038] If the degree of influence on the communication link is moderate, the model matching module first generates an SPDU control frame (Supervisory Proximity Data Unit). This frame is used to inform transceiver B of the communication channel, rate, and coding method, and outputs it to the RF transmission module. The RF transmission module immediately modulates the SPDU control frame into a radio frequency signal and sends it to transceiver B. After the RF receiving module of transceiver B receives the radio frequency signal, it demodulates the SPDU control frame and sends it to the digital management module. After the digital management module proofreads the SPDU control frame, it immediately sets the parameters of the transmission module to the call channel mode (channel 1, 1 kbps, 1 / 2 convolutional coding rate, the same as specified in the CCSDS protocol) through a remote control instruction. After the model matching module generates and sends the SPDU control frame, it then feeds back the degree of influence on the current communication link to the digital management module through telemetry, and sends a remote control instruction to the digital management module to turn off the RF transmission module;

[0039] If the degree of influence on the communication link is severe, the model matching module feeds back this status to the digital management module through telemetry, and sends a remote control instruction to the digital management module to turn off the RF transmission module and the RF receiving module.

[0040] The present invention has been implemented and verified on the UHF band transceiver of the TT&C and data transmission subsystem of the Mars landing and roving vehicle. When the channel conditions change, this method can quickly and accurately evaluate the quality of the current communication link, invert the severity of extreme weather, autonomously adjust the communication mode, and ensure the safety of the detector and high-reliability signal transmission to the greatest extent.

[0041] The invention has low complexity and flexible implementation, and can be widely applied in deep space exploration represented by Mars, providing strong technical support for the establishment of high-reliability Mars relay communication in the future, and having good technical value and economic value.

[0042] The parts not detailed in the present invention belong to the well-known technologies in the art.

Claims

1. A highly reliable communication system based on autonomous care, characterized in that: It includes transceiver A and transceiver B. Transceiver A includes a data management module, a radio frequency receiving module, a process start determination module, a link status evaluation module, a model matching module, and a radio frequency transmitting module; transceiver B includes a radio frequency transmitting module, a data management module, and a radio frequency receiving module; After transceiver B is powered on, the internal radio frequency transmitting module receives the SDU data frame from the data management module, modulates it into a radio frequency signal and sends it to transceiver A. After the radio frequency receiving module inside transceiver A receives the radio frequency signal, it demodulates the SDU data frame and sends it to the data management module, and at the same time smooths the signal-to-noise ratio at intervals of T_delta and outputs it to the process start determination module; The process start determination module compares the input signal-to-noise ratio with the internal start threshold value. When M consecutive input signal-to-noise ratios are less than the start threshold value, the autonomous monitoring process starts. The process start determination module then records the star time scale of the input signal-to-noise ratio, and outputs the signal-to-noise ratio and its corresponding star time scale obtained from the radio frequency receiving module to the link status evaluation module; After the link status evaluation module detects the input of the signal-to-noise ratio, it randomly starts from a certain input signal-to-noise ratio, records the subsequent M input signal-to-noise ratios and their star time scales, obtains the mean value and amplitude of the signal-to-noise ratio during this period according to the link evaluation algorithm, and outputs the mean value of the signal-to-noise ratio, amplitude, the time scale of the first frame signal-to-noise ratio, and the time scale of the last frame signal-to-noise ratio to the model matching module; After the model matching module receives the mean value of the signal-to-noise ratio, amplitude, the time scale of the first frame signal-to-noise ratio, and the time scale of the last frame signal-to-noise ratio, it first retrieves the theoretical signal-to-noise ratio of the corresponding arc segment from the local database according to the time scale of the first frame signal-to-noise ratio and the time scale of the last frame signal-to-noise ratio, and calculates the theoretical mean value and amplitude of the signal-to-noise ratio; secondly, it obtains the degree of influence on the communication link according to the model matching algorithm; if the degree of influence on the communication link is mild, the model matching module feeds back this state to the data management module through telemetry and sends an initialization instruction to the process start determination module, and then ends the autonomous monitoring process; If the degree of influence on the communication link is moderate, the model matching module first generates an SPDU control frame and outputs it to the radio frequency transmitting module. The radio frequency transmitting module immediately modulates the SPDU control frame into a radio frequency signal and sends it to transceiver B. After the radio frequency receiving module of transceiver B receives the radio frequency signal, it demodulates the SPDU control frame and sends it to the data management module. After the data management module proofreads the SPDU control frame, it sets the parameters of the radio frequency transmitting module to the call channel mode through a remote control instruction; after the model matching module generates and sends the SPDU control frame, it feeds back the current degree of influence on the communication link to the data management module through telemetry and sends a remote control instruction to the data management module to turn off the radio frequency transmitting module; if the degree of influence on the communication link is severe, the model matching module feeds back this state to the data management module through telemetry and sends a remote control instruction to the data management module to turn off the radio frequency transmitting module and the radio frequency receiving module.

2. The highly reliable communication system based on autonomous care as claimed in claim 1, wherein: The data field length of the SDU control frame is 1 - 2048 bytes, and the frame format is the same as the frame format specified in the CCSDS protocol.

3. The highly reliable communication system based on autonomous care according to claim 1, wherein: The starting threshold value is the theoretical value of the signal-to-noise ratio of the current arc segment×(1-TH1%); TH1 represents the reduction range of the signal-to-noise ratio under abnormal conditions.

4. The highly reliable communication system based on autonomous care according to claim 1, wherein: The ephemeris time mark is the ephemeris time when the process start determination module receives the signal-to-noise ratio.

5. The highly reliable communication system based on autonomous care according to claim 1, characterized in that: The link evaluation algorithm is used to obtain the signal-to-noise ratio mean and amplitude within the current period, including: Among them, SNR_M2 represents the value of the M2-th input signal-to-noise ratio, and M2 represents the number of input signal-to-noise ratios.

6. The high-reliability communication system based on autonomous care according to claim 1, wherein: Obtaining the degree of impact on the communication link according to the model matching algorithm includes: The link impact assessment factor β is calculated. If β < η1, the link impact is mild; if η1 ≤ β < η2, the link impact is moderate; if β ≥ η2, the link impact is severe. Among them, η1 represents the boundary threshold between mild and moderate impact, and η2 represents the boundary threshold between moderate and severe impact.

7. The highly reliable communication system based on autonomous care according to claim 1, wherein: The SPDU control frame is used to inform the other transceiver of the communication channel, rate and coding method.

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