Redundant TTE end module for carrier rocket electrical system and redundant communication method thereof

Abstract

The invention provides a redundant TTE end module for a carrier rocket electrical system and a redundant communication method thereof, the TTE end module comprises two independently powered FPGAs forming dual redundancy on a logic chip, and each FPGA is connected with two data source interfaces and two TTE network ports to form dual redundancy on a communication link; the redundant communication method of the TTE end module comprises a redundant sending method and a redundant receiving method of TT / RC / BE services. According to the invention, dual redundancy on a logic chip and dual redundancy on a communication link can be realized in a TTE network of a new-generation electrical system of a carrier rocket, so that when a single link fault occurs between equipment and a TTE end module, a single point fault occurs on the logic chip of the TTE end module, and a single link fault occurs between the TTE end module and a TTE switch, the fault of the TTE end module can be prevented from being damaged. And under the condition of a composite fault of a plurality of single-fault combinations, the data can still be normally transmitted, and the fault-tolerant capability is high.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of launch vehicle electrical system, in particular to a redundant TTE end module for launch vehicle electrical system and a redundant communication method thereof. BACKGROUND

[0002] With the increasing amount of communication data in the launch vehicle electrical system, the reliability and real-time performance of the communication network are increasingly required by the electrical system. Traditional low transmission rate bus, such as 1553B, CAN bus technology has gradually failed to meet the development needs of the new generation of launch vehicle electrical system for high bandwidth and high reliability data transmission. Time triggered Ethernet (TTE) bus technology is a new type of communication network based on the modification of standard Ethernet to meet the real-time communication needs. It combines the determinacy, fault tolerance mechanism and real-time performance of time triggered technology with the flexibility, dynamic performance and "best effort" of standard Ethernet, and has the advantages of large capacity, high bandwidth, determinacy, high reliability, strong real-time performance, etc. At the same time, it can be compatible with IEEE 802.3 standard Ethernet.

[0003] TTE bus technology supports three business modes, namely time trigger (TT), rate constraint (RC) and best effort (BE). TT business adopts time trigger mechanism to periodically transmit state information in the network, has the highest priority, and the information bandwidth, transmission delay, jitter and reliability of virtual link (VL) are guaranteed. It is suitable for transmission of critical data (such as master data) with strict real-time requirements. RC business and BE business adopt event trigger (ET) mechanism, in which RC business mainly guarantees the information bandwidth of VL, and through static configuration of bandwidth allocation gap (BAG), data frame length and other information, the data frame interval cannot be less than BAG, which meets the end-to-end transmission delay and jitter requirements, and it is suitable for transmission of critical data (such as measurement data) with less strict real-time requirements. BE business is completely compatible with IEEE 802.3 Ethernet standard, and transmits event information sporadically, with uncertain transmission delay, which is suitable for transmission of non-critical data (such as telemetry video data).

[0004] To improve the reliability of data transmission, the TTE network in the new generation electrical system of a launch vehicle generally uses double redundant links, each device is equipped with a TTE end module, and each communicates with two TTE switches through a communication link. Each TTE end module includes a logic chip connected to a data source interface and two TTE network ports. In the event of a single link failure between the TTE end module and the TTE switch, the TTE end module can still communicate normally with another TTE switch through the other link. However, if a single link failure occurs between the device and the TTE end module, a single point failure occurs in the logic chip of the TTE end module, or a combination of several single failures occurs, data transmission will be abnormal, resulting in abnormal communication network in the electrical system of the launch vehicle. SUMMARY

[0005] The present application aims to provide a redundant TTE end module for a launch vehicle electrical system and a redundant communication method thereof to solve the problems in the prior art.

[0006] The technical solution of the present application is to provide a redundant TTE end module for a launch vehicle electrical system, including two independently powered FPGAs, constituting double redundancy on the logic chip, each FPGA being connected to two data source interfaces and two TTE network ports, constituting double redundancy on the communication link.

[0007] A TTE end module in a new generation electrical system of a launch vehicle has the following functions: (1) supports four-channel 1000M TTE port redundancy function; (2) supports SAE AS 6802 and IEEE 802.3 network protocol specifications; (3) supports SRIO protocol; (4) supports sending or receiving TT / RC / BE services; (5) supports mixed transmission of TT / RC / BE three services, and TT service is not affected by RC / BE service, RC service is not affected by BE service; (6) supports no less than two independent logical partitions, each partition can be configured with independent ports and VLs; (7) supports VLID-based sending gate scheduling; (8) performs integrity check on received TT services, and supports multi-channel adaptive management.

[0008] An FPGA of a TTE end module in a new generation electrical system of a launch vehicle includes a sending processing module, a receiving processing module, a configuration management module, a clock synchronization module and an SRIO interface module.

[0009] The sending processing module is used for classifying, packaging, scheduling and redundantly sending TT, RC and BE three types of service data sent by the CPU through the SRIO interface.

[0010] The receiving processing module is configured to receive data from the network side, and perform identification, verification, redundancy removal and window check, and finally upload valid data to the CPU;

[0011] The configuration management module is configured to statically or dynamically configure various parameters of the TTE end module, including virtual link VL setting, scheduling table loading, port state management, and support system flexible adaptation to different scenarios.

[0012] The clock synchronization module is configured to realize high-precision time synchronization with the TTE network, ensure that all end systems are scheduled and communicated based on a unified time reference, and provide a basis for deterministic transmission of TT services.

[0013] The SRIO interface module serves as a high-speed data path between the FPGA and the external CPU, supports low-latency and high-bandwidth data exchange, and ensures efficient transmission of service data between the computing unit and the communication unit.

[0014] The sending processing module includes a sending packet processing module, a sending queue management module, a sending scheduling module and a sending redundancy management module; wherein:

[0015] The sending packet processing module includes a frame information extraction module, a frame content modification module and a temporary cache FIFO, configured to receive TT / RC / BE services sent by the CPU through SRIO, and send an entry request to the sending queue management module.

[0016] The sending queue management module is configured to solve the output and cache problems of TT services and ET services, and mainly performs two parts of work, 1) reasonably and effectively manages the limited storage resources to meet the needs of services; 2) schedules the logical entry and exit of TT services and ET services.

[0017] The sending scheduling module is configured to perform scheduling functions of the TTE, so as to serve the ET services on the basis of ensuring the sending time of the TT services, and preferentially serve the RC services when serving the ET services, forming a two-level scheduling system.

[0018] The sending redundancy management module is configured to send the TT / RC / BE services after scheduling to the MAC layer through the redundancy network.

[0019] The receiving processing module includes a data receiving identification module, an integrity check module, a receiving redundancy management module and a receiving window check module; wherein:

[0020] The data receiving identification module includes a data register module, a frame header information extraction module, a shunt and a receiving queue buffer, is directly connected with the SRIO interface module, is used for shunting the TT / RC / BE services received from the MAC layer, and transmits the TT / RC / BE services processed through receiving to the CPU through SRIO;

[0021] The integrity check module is used for checking the integrity of the received TT / RC / BE services, and ensuring that the received data frames are continuous.

[0022] The receiving redundancy management module is used for performing the de-redundancy operation on the received TT / RC redundancy services according to rules.

[0023] The receiving window check module is used for checking whether the TT services subjected to the de-redundancy operation arrive within the corresponding receiving window.

[0024] A redundancy communication method of a TTE terminal module in a new generation electrical system of a launch vehicle includes a redundancy sending method and a redundancy receiving method of TT / RC / BE services.

[0025] The redundancy sending method of TT / RC / BE services specifically includes the following steps:

[0026] Step 1, the sending packet processing module receives the TT / RC / BE services sent by the CPU through SRIO, extracts information of the TT / RC / BE services, sends an entry request to the sending queue management module using the extracted service information, adds MAC address, IPv4 header, UDP header and other information to the TT / RC / BE services, and puts the TT / RC / BE services into a temporary buffer FIFO, after receiving the entry reply of the sending queue management module, sends the TT / RC / BE services to the sending queue management module;

[0027] Step 2, the sending queue management module divides the TT services and ET services into two cache areas, for the TT services, when the sending time of the TT services is not met at the current time, sends the TT data frames to the TT cache area and waits for the sending of the sending processing module; for the ET services, when the TT services are being served, the RC and BE data frames are sent to the ET cache area and wait for the sending of the sending processing module;

[0028] Step 3, the sending scheduling module sends a dequeuing request to the sending queue management module, adopts a Time Division Multiple Access (TDMA) scheduling algorithm, strictly sends TT services according to the sending table for periodic TT services, schedules ET services according to TT scheduling state information, preferentially sends RC services in the ET services, sends BE services in the sending gaps of TT / RC services, so that ET services can be served at the same time on the basis of ensuring the sending time of TT services, RC services are preferentially served when ET services are served, and a two-level scheduling system is formed;

[0029] Step 4, the sending redundancy management module adds a redundancy sequence number (SN) with a length of 1 byte to the RC services after scheduling, and the TT / RC services are sent to the MAC layer through redundancy network backup, and the BE services are sent to the MAC layer through redundancy network dispersion.

[0030] The redundancy receiving method of TT / RC / BE services specifically includes the following steps:

[0031] Step a, the data receiving identification module receives TT / RC / BE services from the MAC layer into the TTE end module, extracts information according to the frame header information extraction module, and sends the received TT / RC / BE services to the integrity checking module for shunting;

[0032] Step b, the integrity checking of TT services includes the integrity checking of VL ID, CRC and data frame length, the integrity checking of RC services includes the integrity checking of VL ID, SN number, CRC and data frame length, and the integrity checking of BE services includes the integrity checking of CRC and data frame length; the CRC checking formula is as follows: X 32 +X 26 +X 23 +X 16 +X 12 +X 11 +X 8 +X 7 +X 5 +X 4 +X 2 +X 1 +1;The integrity checking method of the SN number is that the SN number of the first frame sent after the TTE end system is reset is 0, and the SN number is increased by 1 after each frame is sent, and is returned to 1 after being full; the TT / RC services after integrity checking are sent to the receiving redundancy management module, and the BE services are directly put into the corresponding receiving queue buffer area and the corresponding queue flag information is updated;

[0033] Step c, the receiving redundancy management module maintains a Prospective Sequence Number (PSN) for each service according to the end ID of the service, and when a new frame is received, the receiving redundancy management module only needs to compare the SN number of the new frame with the PSN number to determine whether the received data is redundant; since the TT service is periodic, the de-redundancy operation of the TT service is a timer-based redundancy management mode, the receiving redundancy management module maintains a timer for each service according to the end ID of the service, and when a new frame is received, the receiving redundancy management module determines whether the received data is redundant by checking whether the timer is overdue, when the timer is overdue, it is considered that a new frame is received, and when the timer is not overdue, it is considered that redundant data is received;

[0034] Step d, the TT service after the de-redundancy operation is sent to the receiving window checking module, and it is checked whether the TT service arrives in the corresponding receiving window, if yes, it is considered that the TT service passes the receiving window check, otherwise, the frame is discarded;

[0035] Step e, the RC service after the receiving redundancy management and the TT service passing the receiving window check are sent to the corresponding receiving queue buffer area and update the corresponding queue flag information, and are transmitted to the CPU together with the BE service through the SRIO.

[0036] The redundant TTE end module for the electrical system of the launch vehicle and the redundant communication method thereof provided by the application have the following beneficial effects:

[0037] (1) The application adopts the TTE bus technology in the new generation electrical system of the launch vehicle, and has the advantages of large capacity, high bandwidth, determinacy, high reliability, strong real-time performance, etc.

[0038] (2) The TTE end module designed in the application can realize double redundancy on the logical chip and double redundancy on the communication link in the TTE network of the new generation electrical system of the launch vehicle, so as to ensure that data can be normally transmitted when single link failure occurs between the device and the TTE end module, single point failure occurs in the logical chip of the TTE end module, single link failure occurs between the TTE end module and the TTE switch, or composite failure of several single failures occurs, and has high fault tolerance capability. BRIEF DESCRIPTION OF DRAWINGS

[0039] The application will be further described below in combination with the drawings:

[0040] Figure 1 The figure is a TTE network topology diagram in the new generation electrical system of the launch vehicle of the embodiment of the application;

[0041] Figure 2A schematic diagram for TTE end module division in a new generation electrical system of a launch vehicle according to an embodiment of the present application;

[0042] Figure 3 A logic schematic diagram of a sending processing module according to an embodiment of the present application;

[0043] Figure 4 A logic schematic diagram of a receiving processing module according to an embodiment of the present application;

[0044] Figure 5 A schematic diagram of a TTE network data frame format according to an embodiment of the present application. DETAILED DESCRIPTION

[0045] The redundant TTE end module for a launch vehicle electrical system and the redundant communication method thereof according to the present application are described in further detail below in conjunction with the accompanying drawings and specific embodiments. The advantages and features of the present application will be more apparent from the following description and claims. It should be noted that the accompanying drawings are in a very simplified form and all use non-precise ratios, only for the purpose of facilitating and clarifying the description of the embodiments of the present application.

[0046] As shown in Figure 1 , the CPU module includes three independent CPUs, adopts a "two out of three" mode to vote the sending or receiving TT / RC / BE service, and constitutes three redundancies on the data source; the TTE end module includes two independent power supply FPGAs, constituting double redundancies on the logic chip, each FPGA is connected with two data source interfaces and two TTE network ports, constituting double redundancies on the communication link. Taking the CPU sending TT / RC / BE service as an example, the TT / RC / BE service after the "two out of three" voting of the CPU module is sent to the FPGA0 of the TTE end module through CPU0 / CPU1, and sent to the FPGA1 of the TTE end module through CPU0 / CPU2, that is, the FPGA0 and FPGA1 of the TTE end module respectively receive two redundant services sent by the CPU; the FPGA0 / FPGA1 performs sending redundancy processing on the service issued by the CPU, and respectively sends to the TTE switches A and B through the A and B TTE network ports, that is, the TTE switches A and B respectively receive four redundant services sent by the TTE end module. The same service generates eight redundant services through the TTE network, and redundancies are realized in the data source, the logic chip and the communication link, so as to ensure that the data can be normally transmitted when a single link fault occurs between the device and the TTE end module, a single point fault occurs in the logic chip of the TTE end module, a single link fault occurs between the TTE end module and the TTE switch, or a composite fault of several single faults, and has high fault tolerance capability.

[0047] As shown in Figure 2As shown in the figure, the FPGA of the TTE terminal module is composed of a sending processing module, a receiving processing module, a configuration management module, a clock synchronization module and an SRIO interface module. The sending processing module includes a sending packet processing module, a sending queue management module, a sending scheduling module and a sending redundancy management module; the receiving processing module includes a data receiving identification module, an integrity checking module, a receiving redundancy management module and a receiving window checking module.

[0048] As shown in the figure, the redundancy sending method of the TT / RC / BE service specifically includes the following steps: Figure 3

[0049] Step 1: The sending packet processing module receives the TT / RC / BE service sent by the CPU through SRIO, extracts the information of the TT / RC / BE service, sends the entry request to the sending queue management module with the extracted service information, adds the MAC address, IPv4 header, UDP header and other information to the TT / RC / BE service, and puts it into the temporary buffer FIFO. After receiving the entry reply from the sending queue management module, the TT / RC / BE service is sent to the sending queue management module.

[0050] Step 2: The sending queue management module divides the TT service and the ET service into two cache areas. For the TT service, if the sending time is not met at the current time, the TT data frame is sent to the TT cache area and waits for the sending of the sending processing module; for the ET service, the RC and BE data frames are sent to the ET cache area and wait for the sending of the sending processing module when the TT service is being served.

[0051] Step 3: The sending scheduling module sends the de-queue request to the sending queue management module, adopts the TDMA scheduling algorithm, strictly sends the TT service according to the sending table for the periodic TT service, schedules the ET service according to the TT scheduling state information, preferentially sends the RC service in the ET service, and sends the BE service in the sending gap of the TT / RC service, so that the ET service can be served at the same time on the basis of ensuring the sending time of the TT service, and the RC service is preferentially served when the ET service is served, forming a two-level scheduling system.

[0052] Step 4: The sending redundancy management module adds the SN number with a length of 1 byte to the RC service after scheduling, and the TT / RC service is sent to the MAC layer through the redundancy network backup, and the BE service is sent to the MAC layer through the redundancy network dispersion.

[0053] As shown in the figure, the redundancy receiving method of the TT / RC / BE service specifically includes the following steps: Figure 4

[0054] ​​Step a, the data receiving identification module receives TT / RC / BE service from MAC layer into TTE end module, extracts information according to frame header information, and shunts the received TT / RC / BE service into the integrity checking module;

[0055] Step b, the integrity checking of TT service includes VL ID, CRC and data frame length, the integrity checking of RC service includes VL ID, SN number, CRC and data frame length, and the integrity checking of BE service includes CRC and data frame length; the CRC checking formula is as follows: X 32 +X 26 +X 23 +X 16 +X 12 +X 11 +X 8 +X 7 +X 5 +X 4 +X 2 +X 1 +1; the integrity checking mode of SN number is that the SN number of the first frame sent after the TTE end system is reset is 0, and the SN number is increased by 1 after each frame is sent, and is returned to 1 after full; the TT / RC service after integrity checking is sent to the receiving redundancy management module, and the BE service is directly put into the corresponding receiving queue buffer area and the corresponding queue flag information is updated;

[0056] Step c, the receiving redundancy management module maintains a PSN number for each service according to the end ID of the service, and for each service, when a new frame is received, the receiving redundancy management module only needs to compare the SN number of the new frame with the PSN number to determine whether the received data is redundant; since the TT service is periodic, the redundancy removal operation of the TT service is a timer-based redundancy management mode, the receiving redundancy management module maintains a timer for each service according to the end ID of the service, and for each service, when a new frame is received, the receiving redundancy management module determines whether the received data is redundant by checking whether the timer is overdue, when the timer is overdue, it is considered that a new frame is received, and when the timer is not overdue, it is considered that redundant data is received;

[0057] Step d, the TT service after the redundancy removal operation is sent to the receiving window checking module to check whether the TT service arrives within the corresponding receiving window, if yes, it is considered that the TT service passes the receiving window check, otherwise, the frame is discarded;

[0058] Step e, the RC service after the receiving redundancy management and the TT service passing the receiving window check are sent to the corresponding receiving queue buffer area and the corresponding queue flag information is updated, and are transmitted to the CPU together with the BE service through SRIO.

[0059] As Figure 5 shown in the figure, the UDP communication protocol of the TTE network is as follows:

[0060] a) Preamble: 7 bytes, fixed as 0x55;

[0061] b) Start symbol: 1 byte, fixed as 0xD5;

[0062] c) Destination MAC address: 6 bytes, for BE service, fill in the destination MAC address, for TT / RC service, the first 4 bytes are fixed fields determined by the configuration file, and the last 2 bytes are VL ID, indicating the information transmission path, used for TTE switch routing;

[0063] d) Source MAC address: 6 bytes, indicating the data sending source MAC address, for hot standby single machine, single machine involving BE service, the master and standby machines must set different MAC addresses, for cold standby single machine not involving BE service, the master and standby machines should be set to the same MAC address, for cold standby single machine which cannot set the MAC address to the same, when the master and standby machines are switched, it needs to automatically adapt to the change of the MAC address;

[0064] e) Service type: 2 bytes, indicating the network service type, TT / RC service is 0x0800, and BE service is IP core reading data directly issued;

[0065] f) IPv4 header: 20 bytes, indicating the IP protocol information, wherein: version number 4 bits, fixed as 0x4, indicating IPv4; header length 4 bits, fixed as 0x5, indicating that the header length is 20 bytes; service type 8 bits, fixed as all 0x00; total length 16 bits, in bytes, the value range is 46-1500; identification, fragment offset 32 bits, the first 16 bits are the datagram identification, different fragments of the same datagram use the same identification, starting from 0, the identification is incremented by 1 each time an IP datagram is sent, and it is reset to 0 after being full; fragment flag 3 bits, indicating whether the fragment can be fragmented and whether it is the last fragment, fixed as 010, 000; the last 13 bits indicate the fragment offset, fixed as all 0; time to live 8 bits, determined by the configuration tool, and the default in the IP core is all 0; protocol 8 bits, fixed as 0x11, indicating that the data part is handed over to the UDP protocol; header checksum 16 bits, used for checking the 20 bytes of the IPv4 header, each 2 bytes in the IPv4 header are taken as a number, and the sum is calculated by using the inverse code operation, and the inverse code of the sum is the header checksum field; source IP address and destination IP address each 32 bits, indicating the IPv4 address of the data source device and the destination device;

[0066] g) UDP header: 8 bytes, indicating UDP protocol information, wherein: source port, destination port are each 16 bits, indicating data sending port and receiving port; length 16 bits, indicating UDP datagram length (header plus data), in bytes, the value range is 26-1480; checksum 16 bits, used for UDP datagram check, including pseudo header plus data, each 16 bits form a data, and the sum of the original code, and the inverse code of the sum is the checksum field;

[0067] h) Data field: 18-1472 bytes, wherein the TT service is 18-1472 bytes variable length data packet, and the RC service is 17-1471 bytes variable length data packet;

[0068] i) SN number: 1 byte, used by RC message;

[0069] j) CRC check: 4 bytes, same as the standard Ethernet check field, and the check formula is as follows: X 32 +X 26 +X 23 +X 16 +X 12 +X 11 +X 8 +X 7 +X 5 +X 4 +X 2 +X 1 +1.

[0070] The contents not described in detail in the specification belong to the prior art known to those skilled in the art. It is obvious for those skilled in the art that the present application is not limited to the details of the above exemplary embodiments, and the present application can be implemented in other specific forms without departing from the spirit or essential characteristics of the present application. Therefore, the embodiments should be regarded as exemplary and non-limiting, the scope of the present application is defined by the appended claims rather than the above description, and therefore all changes falling within the meaning and scope of the equivalent elements of the claims are intended to be included in the present application.

Claims

1. A redundant TTE end module for electrical systems of launch vehicles, characterized in that, The application relates to a redundant structure for a TTE network, which comprises the following: a first redundant structure; a second redundant structure as a backup redundant structure for replacing the first redundant structure when the first redundant structure as a main redundant structure fails; the first redundant structure is an independently-powered FPGA connected with two data source interfaces and two TTE network ports; the second redundant structure is completely identical with the first redundant structure; the FPGA comprises a sending processing module, a receiving processing module, a configuration management module, a clock synchronization module and an SRIO interface module; the sending processing module is used for classifying, packaging, scheduling and redundantly sending TT, RC and BE type service data sent by a CPU through an SRIO interface; the receiving processing module is used for receiving data from a network side and performing identification, checking, redundancy removal and window checking, and finally uploading effective data to the CPU; the configuration management module is used for statically or dynamically configuring various parameters of a TTE terminal module, including virtual link VL setting, scheduling table loading and port state management, and supports that a system flexibly adapts to different scenes; the clock synchronization module is used for realizing high-precision time synchronization with the TTE network, ensuring that all terminal systems perform scheduling and communication based on a unified time reference, and providing a basis for deterministic transmission of TT service; the SRIO interface module is a high-speed data passage between the FPGA and an external CPU, supports low-delay and high-bandwidth data exchange, and ensures efficient transmission of service data between a calculation unit and a communication unit.

2. The redundant TTE end module for launch vehicle electrical systems of claim 1, wherein, the sending processing module comprises a sending packet processing module, a sending queue management module, a sending scheduling module and a sending redundancy management module; the sending packet processing module comprises a frame information extraction module, a frame content modification module and a temporary buffer FIFO, is used for receiving TT / RC / BE service sent by the CPU through the SRIO, and sends an enqueuing request to the sending queue management module; the sending queue management module is used for solving the output and buffer problems of TT service and ET service, reasonably and effectively manages limited storage resources, enables the resources to meet the demand of service, and simultaneously schedules the logical enqueuing and dequeuing of TT service and ET service; the sending scheduling module is used for realizing the scheduling function of the TTE, simultaneously serves ET service on the basis of ensuring the sending time of TT service, preferentially serves RC service when serving ET service, and forms a two-stage scheduling system; the sending redundancy management module is used for sending TT / RC / BE service after scheduling to the MAC layer through a redundant network.

3. The redundant TTE end module for launch vehicle electrical systems of claim 2, wherein, the receiving processing module comprises a data receiving identification module, an integrity checking module, a receiving redundancy management module and a receiving window checking module; the data receiving identification module comprises a data register module, a frame header information extraction module, a flow divider and a receiving queue buffer, is directly connected with the SRIO interface module, is used for dividing TT / RC / BE service received from the MAC layer, and transmits TT / RC / BE service after receiving processing to the CPU through the SRIO; The integrity checking module is configured to perform integrity checking on the received TT / RC / BE service, so as to ensure that the received data frame is continuous; The receiving redundancy management module is configured to perform de-redundancy operation on the received TT / RC redundancy service according to rules; The receiving window checking module is configured to check whether the TT service after the de-redundancy operation arrives within the corresponding receiving window.

4. Redundant communication method for redundant TTE end module of launch vehicle electrical system, applied to the redundant TTE end module of launch vehicle electrical system as claimed in any one of claims 2 to 3, characterized in that, The redundancy sending method of the TT / RC / BE service comprises the following steps: Step 1, the sending packet processing module receives the TT / RC / BE service sent by the CPU through SRIO, extracts information of the TT / RC / BE service, sends an entry request to the sending queue management module using the extracted service information, adds MAC address, IPv4 header and UDP header information to the TT / RC / BE service, and places the TT / RC / BE service in a temporary buffer FIFO. After receiving the entry reply from the sending queue management module, the TT / RC / BE service is sent to the sending queue management module; Step 2, the sending queue management module divides the TT service and the ET service into two cache areas. For the TT service, if the sending time is not met at the current time, the TT data frame is sent to the TT cache area and waits for the sending of the sending processing module. For the ET service, the RC and BE data frames are sent to the ET cache area and wait for the sending of the sending processing module when the TT service is being served; Step 3, the sending scheduling module sends a dequeue request to the sending queue management module, adopts a TDMA scheduling algorithm, strictly sends the TT service according to the sending table for the periodic TT service, schedules the sending of the ET service according to the TT scheduling state information, preferentially sends the RC service in the ET service, and sends the BE service in the sending gap of the TT / RC service, so that the sending time of the TT service is guaranteed and the ET service can be served at the same time, the RC service is preferentially served when the ET service is served, and a two-level scheduling system is formed; Step 4, the sending redundancy management module adds a SN number with a length of 1 byte to the RC service after scheduling, and the TT / RC service is sent to the MAC layer through the redundancy network backup, and the BE service is sent to the MAC layer through the redundancy network dispersion.

5. The redundant communication method of a redundant TTE end module according to claim 4, characterized in that, The redundancy receiving method of the TT / RC / BE service comprises the following steps: Step a, the data receiving identification module receives the TT / RC / BE service transmitted from the MAC layer to the TTE module, performs shunting on the received TT / RC / BE service according to the information extracted by the frame header information extraction module, and sends the TT / RC / BE service to the integrity checking module; The integrity check of the TT service in step b includes the integrity check of VL ID, CRC and data frame length, the integrity check of the RC service includes the integrity check of VL ID, SN number, CRC and data frame length, and the integrity check of the BE service includes the integrity check of CRC and data frame length; the CRC check formula is as follows: X 32 + X 26 + X 23 + X 16 + X 12 + X 11 + X 8 + X 7 + X 5 + X 4 + X 2 + X 1 + 1; the integrity check mode of the SN number is that the SN number of the first frame sent by the TTE terminal system after system reset is 0, and the SN number is increased by 1 after each frame is sent, and is returned to 1 after full increase; the TT / RC service after integrity check is sent to the receiving redundancy management module, and the BE service is directly put into the corresponding receiving queue buffer area and the corresponding queue flag information is updated; Step c, the receiving redundancy management module maintains a PSN number for each service according to the end ID of the service, and for each service, when a new frame is received, the receiving redundancy management module only needs to compare the SN number of the new frame with the PSN number to determine whether the received data is redundant; the receiving redundancy management module maintains a timer for each service according to the end ID of the service, and for each service, when a new frame is received, the receiving redundancy management module determines whether the received data is redundant by checking whether the timer is overdue, when the timer is overdue, it is considered that a new frame is received, and when the timer is not overdue, it is considered that redundant data is received; Step d, the TT service after the de-redundancy operation is sent to the receiving window checking module, and it is checked whether the TT service arrives within the corresponding receiving window, if yes, it is considered that the TT service passes the receiving window check, otherwise, the frame is discarded; Step e, the RC service after the receiving redundancy management and the TT service passing the receiving window check are sent to the corresponding receiving queue buffer area and the corresponding queue flag information is updated, and together with the BE service, they are transmitted to the CPU through SRIO.

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