Disclosure of Invention
Aiming at the requirements of high availability and high continuity of a navigation satellite, the invention provides an autonomous integrated monitoring system and method for a navigation satellite signal and a telegraph text, so as to realize the step-by-step positioning of the faults of all subsystems related to the load and directly related to the signal and the telegraph text.
A navigational satellite signal and text autonomous integrated monitoring system, comprising:
the comprehensive monitoring unit is used for monitoring the integrity of the uplink navigation signal, the downlink navigation signal and the telegraph text, and comprises:
the uplink injection signal monitoring module is used for ranging and information demodulation of uplink injection signals to obtain a reference ranging value, and the reference ranging value is used for integrity monitoring of an uplink injection receiving subsystem; a text generation and comparison module for performing the following actions:
receiving message information from the upper note receiving subsystem, and generating a downlink navigation message according to the upper note information;
receiving navigation message information sent by an information processing subsystem;
receiving a downlink navigation message demodulated by a low-power navigation signal monitoring module; and
comparing the downlink navigation message generated according to the upper note information, the navigation message information sent by the information processing subsystem and the downlink navigation message demodulated by the low-power navigation signal monitoring module;
the low-power navigation signal monitoring module is used for capturing, tracking and demodulating a navigation signal generated by the information processing subsystem, calculating a distance measurement value and signal power, demodulating to obtain a navigation message, and comparing the distance measurement value and the signal power with a preset reference value; the high-power navigation signal monitoring module is used for capturing, tracking and demodulating the navigation signal amplified by the high-power subsystem, calculating a distance measurement value and signal power, and comparing the distance measurement value and the signal power with a preset reference value; and
and the health judgment and processing unit is used for positioning the fault according to the monitoring result of the comprehensive monitoring unit.
The invention also provides a navigation satellite signal and telegraph text autonomous integrated monitoring method, which comprises the following steps:
monitoring the integrity of the upper note receiving subsystem, comprising:
receiving the ground uplink injection signal after power division through an uplink injection signal monitoring module;
the uplink injection signal monitoring module is used for carrying out ranging and information demodulation on the uplink injection signal and sending the ranging result to the health judgment and processing unit; and
comparing the distance measurement result of the upper injection signal monitoring module with the distance measurement value of the upper injection receiving subsystem through a health judgment and processing unit to complete fault positioning of the upper injection receiving subsystem:
if the ranging value of the upper injection receiving subsystem jumps abnormally and the ranging result of the upper injection signal monitoring module is normal, the upper injection receiving subsystem is indicated to be abnormal;
if the distance measurement result of the upper injection signal monitoring module is abnormally jumped and the distance measurement value of the upper injection receiving subsystem is normal, the upper injection signal monitoring module is indicated to be abnormal;
if the ranging value of the upper injection receiving subsystem and the ranging result of the upper injection signal monitoring module are abnormally jumped, indicating that the ground upper injection signal or the upper injection receiver antenna and the power divider are abnormal; and
if the distance measurement value of the upper injection receiving subsystem and the distance measurement result of the upper injection signal monitoring module are normal, it is indicated that each system is normal;
monitoring the integrity of signals of an information processing subsystem and a high-power subsystem, comprising:
receiving a low-power navigation downlink signal generated by the information processing subsystem through a low-power navigation signal monitoring module;
tracking the low-power navigation downlink signal through a low-power navigation signal monitoring module, calculating to obtain a distance measurement value and signal power, and demodulating to obtain a downlink navigation message;
comparing the ranging value and the signal power with a reference value recorded in a low-power navigation signal monitoring module through the low-power navigation signal monitoring module, and if the difference value between the ranging value and the reference value exceeds a preset threshold, generating a low-power navigation signal integrity abnormal signal;
receiving a downlink navigation signal amplified by a high-power subsystem through a high-power navigation signal monitoring module;
processing and measuring the downlink navigation signal amplified by the high-power subsystem through a high-power navigation signal monitoring module to obtain a ranging value and signal power;
comparing the distance measurement value and the signal power with a reference value recorded in the high-power navigation signal monitoring module through the high-power navigation signal monitoring module, and if the difference value between the distance measurement value and the reference value exceeds a preset threshold, generating a high-power navigation signal integrity abnormal signal; and
and performing signal integrity fault location by a health judgment and processing unit according to the low-power navigation signal integrity abnormal signal, the high-power navigation signal integrity abnormal signal and the signal integrity abnormal signal of the integrity monitoring receiver:
if the abnormal integrity signal of the low-power navigation signal is received, and the abnormal integrity signal of the high-power navigation signal and the abnormal integrity signal of the integrity monitoring receiver are not received at the same time, the abnormal integrity signal of the low-power navigation signal is indicated;
if the signal integrity abnormal signal of the integrity monitoring receiver is received, and the high-power navigation signal integrity abnormal signal and the low-power navigation signal integrity abnormal signal are not received at the same time, the integrity monitoring receiver is abnormal;
if the high-power navigation signal integrity abnormal signal is received, and the low-power navigation signal integrity abnormal signal and the signal integrity abnormal signal of the integrity monitoring receiver are not received at the same time, the high-power navigation signal monitoring module is abnormal;
if the abnormal signal of the integrity of the high-power navigation signal and the abnormal signal of the integrity monitoring receiver are received, and meanwhile the abnormal signal of the integrity of the low-power navigation signal is not received, the high-power subsystem is indicated to be abnormal;
if the high-power navigation signal integrity abnormal signal, the signal integrity abnormal signal of the integrity monitoring receiver and the low-power navigation signal integrity abnormal signal are received at the same time, the fact that the information processing subsystem is abnormal is indicated; and
if the high-power navigation signal integrity abnormal signal, the signal integrity abnormal signal of the integrity monitoring receiver and the low-power navigation signal are not received
The abnormal integrity signals of the navigation signals indicate that all signal monitoring systems are normal; and monitoring the integrity of the telegraph text of the information processing subsystem and the high-power subsystem, wherein the monitoring comprises the following steps:
the method comprises the steps that message information from an upper note receiving subsystem, navigation message information sent by an information processing subsystem and a downlink navigation message demodulated by a low-power navigation signal monitoring module are received through a message generating and comparing module;
generating a downlink navigation message according to the message information from the upper note receiving subsystem through a message generating and comparing module;
comparing the downlink navigation message demodulated by the low-power navigation signal monitoring module with the downlink navigation message generated by the message generating and comparing module through a message generating and comparing module, and if the comparison is not consistent, generating a message integrity abnormal signal of the message generating and comparing module; and
and through a health judgment and processing unit, carrying out message integrity fault location according to the message integrity abnormal signal of the message generation and comparison module and the message integrity abnormal signal of the integrity monitoring receiver:
if the message integrity abnormal signal of the message generation and comparison module is received and the message integrity abnormal signal of the integrity monitoring receiver is not received, the message generation and comparison module is abnormal;
if the message integrity abnormal signal of the integrity monitoring receiver is received and the message integrity abnormal signal of the message generation and comparison module is not received, the integrity monitoring receiver is abnormal;
if the message integrity abnormal signal of the integrity monitoring receiver and the message integrity abnormal signal of the message generating and comparing module are received at the same time, the message processing subsystem is abnormal; and
if the message integrity abnormal signal of the integrity monitoring receiver and the message integrity abnormal signal of the message generating and comparing module are not received, the message generation and judgment of each system are normal.
Further, the monitoring of the integrity of the uplink injection receiving subsystem further includes confirming the information integrity of the uplink injection signal through CRC check.
Further, the generating of the signal integrity anomaly signal of the integrity monitoring receiver comprises:
receiving the downlink navigation signal amplified by the high-power subsystem through the integrity monitoring receiver;
processing and measuring the downlink navigation signal amplified by the high-power subsystem through an integrity monitoring receiver to obtain a ranging value and signal power; and
and comparing the ranging value and the signal power with a reference value recorded in the integrity monitoring receiver through the integrity monitoring receiver, and if the difference value between the ranging value and the reference value and the difference value between the signal power and the reference value exceed a preset threshold, generating a signal integrity abnormal signal of the integrity monitoring receiver.
Further, the generating of the message integrity anomaly signal of the integrity monitoring receiver comprises:
receiving the telegraph text information from the upper note receiving subsystem through the integrity monitoring receiver, and demodulating the telegraph text information in the navigation signal output by the high-power subsystem;
generating a downlink navigation message 1 according to the message information from the upper note receiving subsystem through an integrity monitoring receiver;
demodulating a downlink navigation message 2 according to the downlink navigation signal amplified by the high-power subsystem through an integrity monitoring receiver;
and comparing the navigation message information sent by the information processing subsystem, the downlink navigation message 1 and the downlink navigation message 2 through the integrity monitoring receiver, and if the comparison is not consistent, generating a message integrity abnormal signal of the integrity monitoring receiver.
The invention also provides a navigation satellite which is provided with the navigation satellite signal and message autonomous integrated monitoring system.
The navigation satellite signal and message autonomous integrated monitoring system and method provided by the invention are applied to a navigation satellite, monitor an upper injection receiving subsystem, an information processing subsystem and a high-power subsystem, realize autonomous monitoring of the processing integrity of an uplink signal, the generation integrity of a downlink signal and the arrangement integrity of a downlink message of a navigation satellite load subsystem, are convenient for sharing time-frequency and hardware resources and save satellite-borne resources. The system and the method realize the step-by-step positioning of the faults of each subsystem directly related to the signals and the telegraph text related to the load through a highly integrated comprehensive monitoring unit, do not need ground intervention compared with the traditional fault positioning based on ground remote measurement, and have the advantages of automatic alarm, small alarm time delay and the like. Meanwhile, the system and the method realize the integrity monitoring of the whole system and the whole functional chain without single points and dead angles, carry out single-machine-level positioning by a redundancy comparison method, facilitate subsequent fault recovery, eliminate false alarms caused by the faults of the monitoring units and improve the reliability of the system.
Detailed Description
In the following description, the present invention is described with reference to examples. One skilled in the relevant art will recognize, however, that the embodiments may be practiced without one or more of the specific details, or with other alternative and/or additional methods, materials, or components. In other instances, well-known structures, materials, or operations are not shown or described in detail to avoid obscuring aspects of the invention. Similarly, for purposes of explanation, specific numbers, materials and configurations are set forth in order to provide a thorough understanding of the embodiments of the invention. However, the invention is not limited to these specific details. Further, it should be understood that the embodiments shown in the figures are illustrative representations and are not necessarily drawn to scale.
Reference in the specification to "one embodiment" or "the embodiment" means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the invention. The appearances of the phrase "in one embodiment" in various places in the specification are not necessarily all referring to the same embodiment.
It should be noted that the embodiment of the present invention describes the process steps in a specific order, however, this is only for the purpose of illustrating the specific embodiment, and does not limit the sequence of the steps. Rather, in various embodiments of the present invention, the order of the steps may be adjusted according to process adjustments.
The signal and information processing integrity of the load subsystem comprises uplink signal processing integrity, uplink information processing integrity, downlink signal generation integrity and downlink text arrangement integrity, and related subsystems comprise an uplink transmission receiving subsystem, an information processing subsystem and a high-power subsystem.
The invention discloses a navigation satellite signal and telegraph text autonomous integrated monitoring system and method, and a navigation satellite provided with the system, which realize the step-by-step positioning of the faults of each subsystem directly related to signals and telegraph texts, which are related to the load of the navigation satellite, through a large-capacity FPGA. The system and method are further described with reference to the accompanying drawings.
Fig. 1 is a schematic structural diagram of an autonomous integrated navigation satellite signal and text monitoring system according to an embodiment of the present invention. As shown in fig. 1, an autonomous integrated monitoring system for navigation satellite signals and messages includes an integrated monitoring unit 233 and a health decision and processing unit 232:
the integrated monitoring unit 233 is configured to monitor integrity of the uplink navigation signal, the downlink navigation signal, and the text, and includes an uplink signal monitoring module 101, a text generation and comparison module 102, a low-power navigation signal monitoring module 103, and a high-power navigation signal monitoring module 104:
the uplink injection signal monitoring module 101 is configured to perform ranging and information demodulation on an uplink injection signal to obtain a reference ranging value, where the reference ranging value is used for integrity monitoring of an uplink injection receiving subsystem;
the text generation and comparison module 102 is configured to monitor the text integrity of the information processing subsystem, and includes:
receiving message information from the upper note receiving subsystem, and generating a downlink navigation message according to the upper note information;
receiving navigation message information sent by an information processing subsystem;
receiving a downlink navigation message demodulated by a low-power navigation signal monitoring module;
comparing the downlink navigation message generated according to the upper note information, the navigation message information sent by the information processing subsystem and the downlink navigation message demodulated by the low-power navigation signal monitoring module; and
and generating a message integrity abnormal signal of the message generation and comparison module.
The low-power navigation signal monitoring module 103 is configured to monitor signal integrity of the information processing subsystem, and includes capturing, tracking, and demodulating a navigation signal generated by the information processing subsystem, calculating a distance measurement value and a signal power, demodulating to obtain a navigation message, comparing the distance measurement value and the signal power with a preset reference value, and generating a low-power navigation signal integrity abnormal signal; and
the high-power navigation signal monitoring module 104 is configured to monitor the signal integrity of the high-power subsystem, and includes capturing, tracking, and demodulating a navigation signal amplified by the high-power subsystem, calculating a distance measurement value and a signal power, comparing the distance measurement value and the signal power with a preset reference value, and generating a low-power navigation signal integrity abnormal signal; and
the health judgment and processing unit 232 is configured to perform fault location according to the monitoring result of the integrated monitoring unit.
Fig. 2 is a schematic structural diagram of a navigation satellite according to an embodiment of the present invention. As shown in fig. 2, the navigation satellite comprises a satellite platform 201, a load subsystem 202 and an autonomous health manager 203, wherein:
the load subsystem 202 receives the navigation information of ground operation control upper notes, and modulates the navigation information to downlink navigation signals to be sent to the ground for ground users to carry out positioning calculation, and the method comprises the following steps:
the time-frequency subsystem 221, which is used to provide high-precision time-frequency reference and time-frequency signals required by other subsystems, includes:
a main clock 2211 for generating 10MHz time-frequency signals;
the standby clock 2212 is used for generating 10MHz time-frequency signals, when the navigation satellite operates, the standby clock is started up at the same time, the standby clock 2212 performs hot backup, and when the main clock 2211 works abnormally, a time-frequency system is quickly and seamlessly switched to the standby clock 2212;
the base frequency processor 2213 is configured to generate a 10.23MHz time-frequency signal based on the 10MHz signal generated by the main clock, and amplify and output the 10.23MHz signal and the 10MHz signal generated by the main clock to the frequency synthesizer; and
a frequency synthesizer 2214, configured to perform frequency synthesis with the 10.23MHz and 10MHz time-frequency signals output by the baseband processor 2213 as reference signals, so as to obtain frequencies required by the upper note receiving processor 2221, the information processing unit 2231, the integrity monitoring receiver 2232, the autonomous health manager 203, and other units;
an upper injection receiving subsystem 222, configured to complete uplink injection reception sent by the ground operation and control system, and demodulate navigation information and parameters, including an upper injection receiving processor 2221 and an upper injection receiver antenna 2222;
the information processing subsystem 223 is configured to process the instruction and the parameter demodulated by the uplink injection subsystem, perform corresponding processing according to the instruction requirement, generate a low-power downlink navigation signal, and modulate the navigation information injected on the ground onto the navigation signal according to a specific format, and includes an information processor 2231 and an integrity monitoring receiver 2232; and
the high-power subsystem 224 is configured to perform power amplification on a low-power downlink navigation signal, and send the downlink navigation signal to the ground through a downlink antenna, and includes a triplexer 2241, an RNSS antenna array 2242, a master transmission link 2243, and a backup transmission link 2244, where the triplexer 2241 receives a radio frequency signal sent by the information processor 2231 through the master transmission link 2243 or the backup transmission link 2244, processes the radio frequency signal, and sends the radio frequency signal to the RNSS antenna array 2242; and
the autonomous health manager 203 is configured to receive radio frequency signals and data of the subsystems of the load subsystem 202 and the satellite platform, and autonomously monitor and process a health state of the navigation satellite. The autonomous health manager 203 includes a time-frequency monitoring unit 231, an integrated monitoring unit 233, and a health decision and processing unit 232.
Fig. 3-5 are schematic flow charts illustrating steps of a navigation satellite signal and text autonomous integrated monitoring method according to an embodiment of the present invention. A navigation satellite signal and telegraph text autonomous integrated monitoring method comprises the steps of monitoring the integrity of an upper note receiving subsystem, monitoring the signal integrity of an information processing subsystem and a high-power subsystem, and monitoring the telegraph text integrity of the information processing subsystem and the high-power subsystem.
The monitoring of the integrity of the upper note receiving subsystem comprises the integrity monitoring of an uplink signal processing unit and the integrity monitoring of an upper note communication module unit, wherein the integrity monitoring of the uplink signal processing unit comprises the signal integrity monitoring and the information integrity monitoring. In one embodiment of the invention, the information integrity monitoring is confirmed by a CRC check. The signal integrity monitoring mainly monitors whether the ranging value jumps or not and confirms through transverse comparison. Fig. 3 is a flowchart illustrating monitoring of the integrity of the attention surcharge receiver subsystem according to an embodiment of the present invention, and as shown in fig. 3, the monitoring of the integrity of the attention surcharge receiver subsystem includes:
step 301, receiving a signal. And the ground uplink injection signal is subjected to power division at the rear end of the upper injection antenna through a power divider, wherein one path of the uplink injection signal is output to the upper injection receiving subsystem, and the other path of the uplink injection signal is output to the autonomous health management machine. Receiving the ground uplink injection signal after power division through an uplink injection signal monitoring module;
step 302, signal processing. The uplink injection signal monitoring module is used for carrying out ranging and information demodulation on the uplink injection signal and sending the ranging result to a health judgment and processing unit B; and
step 303, fault location. Comparing the distance measurement result of the upper injection signal monitoring module with the distance measurement value of the upper injection receiving subsystem through a health judgment and processing unit to complete fault positioning of the upper injection receiving subsystem:
if the ranging value of the upper injection receiving subsystem jumps abnormally and the ranging result of the upper injection signal monitoring module is normal, the upper injection receiving subsystem is indicated to be abnormal;
if the distance measurement result of the upper injection signal monitoring module is abnormally jumped and the distance measurement value of the upper injection receiving subsystem is normal, the upper injection signal monitoring module is indicated to be abnormal;
if the ranging value of the upper injection receiving subsystem and the ranging result of the upper injection signal monitoring module are abnormally jumped, indicating that the ground upper injection signal or the upper injection receiver antenna and the power divider are abnormal; and
and if the distance measurement value of the upper injection receiving subsystem and the distance measurement result of the upper injection signal monitoring module are normal, indicating that all the systems are normal.
The information processing subsystem is used for generating a low-power downlink navigation signal, the high-power subsystem is used for amplifying the power of the navigation signal, and the two subsystems have certain coupling, so that the two subsystems are put together for integrity redundancy comparison monitoring. The integrity of the information processing subsystem comprises downlink signal generation integrity and downlink text arrangement integrity. The integrity of downlink message arrangement is mainly embodied in the correctness of navigation message arrangement, and the integrity of downlink signal generation is mainly embodied in the integrity of signal power and signal ranging values. The monitoring of the integrity of the downlink signal generation is completed by a low-power navigation signal monitoring module of the comprehensive monitoring unit. The integrity of the downlink text editing is finished by a text generation and comparison module of the comprehensive monitoring unit; the integrity monitoring of the high-power subsystem mainly comprises the integrity of navigation signals, and the abnormity comprises the jump of a ranging value and the jump of signal power. On-track operation of high-power standalone involves safety issues, so the decision and operation of on-track high-power subsystems is very careful. In order to increase reliability and carry out redundancy comparison, the fault of the high-power subsystem is completed by the integrity monitoring receiver, the low-power navigation signal monitoring module and the high-power navigation signal monitoring module together.
Fig. 4 is a flow chart illustrating signal integrity monitoring for an information handling subsystem and a high power subsystem according to an embodiment of the present invention. As shown in fig. 4, the monitoring of the integrity of the signals of the information processing subsystem and the high power subsystem includes:
step 401, determining the integrity of the low-power navigation signal, including:
a low-power navigation downlink signal generated by the information processing subsystem is coupled to a low-power navigation signal monitoring module;
tracking the low-power navigation downlink signal through a low-power navigation signal monitoring module, calculating to obtain a distance measurement value and signal power, and demodulating to obtain a downlink navigation message;
and
comparing the distance measurement value and the signal power with a reference value recorded in the small-power navigation signal monitoring module through the small-power navigation signal monitoring module, and if the difference value between the distance measurement value and the reference value exceeds a preset threshold, generating a small-power navigation signal integrity abnormal signal Sxx;
Step 402, judging the integrity of the high-power navigation signal, including:
receiving a downlink navigation signal amplified by a high-power subsystem through a high-power navigation signal monitoring module;
processing and measuring the downlink navigation signal amplified by the high-power subsystem through a high-power navigation signal monitoring module to obtain a ranging value and signal power; and
comparing the distance measurement value and the signal power with a reference value recorded in the high-power navigation signal monitoring module through the high-power navigation signal monitoring module, and if the difference value between the distance measurement value and the reference value exceeds a preset threshold, generating a high-power navigation signal integrity abnormal signal Sdx;
Step 403, judging the signal integrity of the integrity monitoring receiver, including:
receiving the downlink navigation signal amplified by the high-power subsystem through the integrity monitoring receiver;
processing and measuring the downlink navigation signal amplified by the high-power subsystem through an integrity monitoring receiver to obtain a ranging value and signal power; and
comparing the ranging value and the signal power with a reference value recorded in the integrity monitoring receiver through the integrity monitoring receiver, and if the difference value between the ranging value and the reference value exceeds a preset threshold, generating a signal integrity abnormal signal S of the integrity monitoring receiverwx(ii) a And
step 404, fault location. According to the abnormal signal S of the integrity of the low-power navigation signal by a health judgment and processing unitxxThe high-power navigation signal integrity abnormal signal SdxAnd a signal integrity abnormal signal S of the integrity monitoring receiverwxAnd positioning signal integrity fault:
if the abnormal integrity signal of the low-power navigation signal is received, and the abnormal integrity signal of the high-power navigation signal and the abnormal integrity signal of the integrity monitoring receiver are not received at the same time, the abnormal integrity signal of the low-power navigation signal is indicated;
if the signal integrity abnormal signal of the integrity monitoring receiver is received, and the high-power navigation signal integrity abnormal signal and the low-power navigation signal integrity abnormal signal are not received at the same time, the integrity monitoring receiver is abnormal;
if the high-power navigation signal integrity abnormal signal is received, and the low-power navigation signal integrity abnormal signal and the signal integrity abnormal signal of the integrity monitoring receiver are not received at the same time, the high-power navigation signal monitoring module is abnormal;
if the abnormal signal of the integrity of the high-power navigation signal and the abnormal signal of the integrity monitoring receiver are received, and meanwhile the abnormal signal of the integrity of the low-power navigation signal is not received, the high-power subsystem is indicated to be abnormal;
if the high-power navigation signal integrity abnormal signal, the signal integrity abnormal signal of the integrity monitoring receiver and the low-power navigation signal integrity abnormal signal are received at the same time, the fact that the information processing subsystem is abnormal is indicated; and
and if the high-power navigation signal integrity abnormal signal, the signal integrity abnormal signal of the integrity monitoring receiver and the low-power navigation signal integrity abnormal signal are not received, indicating that all signal monitoring systems are normal.
Fig. 5 is a flow chart illustrating text integrity monitoring of an information processing subsystem and a high power subsystem according to an embodiment of the present invention. As shown in fig. 5, the monitoring of the integrity of the text messages of the information processing subsystem and the high-power subsystem includes:
step 501, the text integrity judgment of the text generation and comparison module comprises:
receiving the telegram information from the upper note receiving subsystem and the downlink navigation telegram demodulated by the low-power navigation signal monitoring module through a telegram generating and comparing module;
generating a downlink navigation message according to the message information from the upper note receiving subsystem through a message generating and comparing module; and
through a message generating and comparing module, the navigation message information sent by the information processing subsystem, the downlink navigation message demodulated by the low-power navigation signal monitoring module and the downlink navigation message generated by the message generating and comparing module are compared, and if the comparison is not consistent, a message integrity abnormal signal S of the message generating and comparing module is generateddd;
Step 502, the integrity of the text message of the integrity monitoring receiver is judged, which includes:
receiving the telegraph text information from the upper note receiving subsystem through the integrity monitoring receiver, and demodulating the telegraph text information in the navigation signal output by the high-power subsystem;
generating a downlink navigation message 1 according to the message information from the upper note receiving subsystem through an integrity monitoring receiver;
demodulating a downlink navigation message 2 according to the downlink navigation signal amplified by the high-power subsystem through an integrity monitoring receiver;
comparing the navigation message information sent by the information processing subsystem, the downlink navigation message 1 and the downlink navigation message 2 through an integrity monitoring receiver, and if the comparison is not consistent, generating a message integrity abnormal signal S of the integrity monitoring receiverwd(ii) a And
step 503, fault location. Generating and comparing a message integrity abnormal signal S of the module according to the message through a health judgment and processing unit BddAnd a message integrity anomaly signal S of the integrity monitoring receiverwdAnd carrying out message integrity fault location:
if the message integrity abnormal signal of the message generation and comparison module is received and the message integrity abnormal signal of the integrity monitoring receiver is not received, the message generation and comparison module is abnormal;
if the message integrity abnormal signal of the integrity monitoring receiver is received and the message integrity abnormal signal of the message generation and comparison module is not received, the integrity monitoring receiver is abnormal;
if the message integrity abnormal signal of the integrity monitoring receiver and the message integrity abnormal signal of the message generating and comparing module are received at the same time, the message processing subsystem is abnormal; and
if the message integrity abnormal signal of the integrity monitoring receiver and the message integrity abnormal signal of the message generating and comparing module are not received, the message generation and judgment of each system are normal.
While various embodiments of the present invention have been described above, it should be understood that they have been presented by way of example only, and not limitation. It will be apparent to persons skilled in the relevant art that various combinations, modifications, and changes can be made thereto without departing from the spirit and scope of the invention. Thus, the breadth and scope of the present invention disclosed herein should not be limited by any of the above-described exemplary embodiments, but should be defined only in accordance with the following claims and their equivalents.