E1 routing protection switching equipment

Abstract

The present invention relates to an E1 routing protection switching device, and belongs to the field of communication control. The E1 routing protection switching device of the present invention comprises an E1 interface module, an FPGA module, an embedded control unit, a network communication and peripheral unit, and a whole machine power supply module; the E1 interface module comprises a user side E1 interface, a main channel E1 interface, and a backup channel E1 interface. The present invention can switch to another route without damage when any alarm or error code among LOS, LOF, and AIS occurs in the currently transmitting route; the single-machine additional delay of the present invention is less than 1.4ms, and the error code detection is realized in a relatively short time, without a large amount of cached data, and the additional delay of the device is small; it has the function of main channel / backup channel delay test.

Description

Technical Field

[0001] The invention relates to the technical field of communication control, in particular to E1 routing protection switching equipment. Background Art

[0002] Stability control and relay protection are devices used by the power system to monitor the operation of the power grid in real time and control system switching, tripping (load shedding), and switch switching when abnormalities occur in the high-voltage lines of power plants and distribution stations. Stability control and relay protection are used in pairs. The devices at both ends collect parameters such as voltage, current, and frequency on the high-voltage transmission line to determine whether to control system switching, load shedding, switch switching, etc. The communication interface of stability control and relay protection is generally a low-speed optical fiber interface. This is mainly because the stability control equipment and relay protection equipment are installed in strong electromagnetic fields, and the optical fiber interface has a good pit interference ability. The communication between a pair of stability control and relay protection equipment only requires an E1 bandwidth to meet its performance requirements. In order to ensure the reliability of data transmission of stability control equipment and relay protection equipment, the 1+1 backup method of communication transmission lines is an effective method adopted by power operators to solve transmission reliability. In addition, power operators have redundant transmission lines, which provides a material basis for the 1+1 backup method. There are several solutions based on the 1+1 backup method.

[0003] The first method is dual-fiber direct connection. Due to its high cost and poor reliability, this method is only used between small substations.

[0004] The second method is optical / electrical conversion equipment + PCM multiplexing equipment + SDH self-healing ring. In the relay protection system, the biggest weakness of the SDH self-healing ring is that it cannot guarantee that bidirectional data can pass through the same route, and thus cannot guarantee that the two directions have the same delay, but the same delay in both directions is a basic requirement of the relay protection equipment, otherwise the relay protection equipment cannot work properly.

[0005] The third method is optical / electrical conversion equipment + PCM multiplexing equipment + E1 manual switching. Due to the diversity of protection equipment and transmission channels, manual switching and maintenance are inconvenient. Once a failure occurs, manual switching will cause complete interruption of communication, and the safety of equipment use will be greatly affected. Summary of the invention

[0006] The present invention aims at the deficiencies of the prior art and provides an E1 routing protection switching device, and its technical solution is as follows:

[0007] E1 routing protection switching equipment, including E1 interface module, FPGA module, embedded control unit, network communication and peripheral unit;

[0008] The E1 interface module includes a user side E1 interface, a main channel E1 interface, and a standby channel E1 interface;

[0009] The E1 interface module implements E1 data reception, transmission, loopback control, HDB3 encoding and decoding, clock recovery smoothing, and jitter attenuation;

[0010] The FPGA module detects data alarms, frame synchronization processing, CRC check, and rate adaptation from the user side E1 interface, and then inserts the ID and official communication data, and sends them out through the main channel E1 interface and the backup channel E1 interface respectively;

[0011] The FPGA module also detects data alarms, frame synchronization processing, CRC check, rate adaptation, RAM data alignment, and switching control from the main channel E1 interface and the backup channel E1 interface, selects a channel of intact data without alarms or errors, and sends it out through the user side E1 interface to achieve lossless switching of data;

[0012] The embedded control unit is used to complete the working mode setting of the equipment, the collection and display of alarms, and communicate with the network and peripheral units.

[0013] As a further solution of the present invention, the network communication and peripheral unit includes an auxiliary computer interface, an HDMI display interface, a USB keyboard and mouse interface, a MiniPCIE interface, a SATA hard disk interface, and a hard disk power interface.

[0014] As a further solution of the present invention, the process of data processing of the E1 routing protection switching device includes the following steps:

[0015] The sending part of the E1 routing protection switching device receives data from the user side E1 interface, implements frame synchronization, decoding, inserts time stamp signals, device service contact data, channel ID and CRC check data according to the set data format, forms two new PCM31C frames, and sends them to the main channel E1 interface and the backup channel E1 interface respectively, completing the sending of the main channel E1 data and the backup channel E1 data;

[0016] The receiving part of the E1 routing protection switching device receives data from the main channel E1 interface and the backup channel E1 interface, performs alarm detection, frame synchronization detection, and frame error and CRC error performance detection on the data of the main channel E1 interface and the backup channel E1 interface, extracts the main channel / backup channel time stamp, obtains the user ID, extracts the device service contact data, uses the clock smoothing phase lock implemented by the full digital phase-locked loop, stores the data blocks of a specific sequence to the corresponding positions of the RAM according to the time stamp signal of the main channel / backup channel, completes the data alignment of the main channel / backup channel, completes the switching of the main channel E1 interface / backup channel E1 interface data and clock through the alarm detection and CRC error detection of the signal from the main channel E1 interface / backup channel E1 interface, selects a channel data without alarm and error to be sent out through the user side E1 interface, and realizes the lossless switching of user data.

[0017] As a further solution of the present invention, the E1 routing protection switching device lossless automatic switching includes the following steps:

[0018] The sending part of the E1 routing protection switching device includes a time stamp insertion module, an ID insertion module for interconnection and channel identification between devices, a business message insertion module for inserting official communication data between devices, and a CRC check module for CRC check. The insertion of the time stamp uses certain specific idle time slots of G.704, the insertion of the ID is used for interconnection and channel identification between devices, the IDs of the main channel and the backup channel are different, and the official communication data is used for communication, device status acquisition, channel delay calculation and mutual control between a pair of devices; the data of the inserted time stamp, ID and communication official message are sent to the main channel E1 interface / backup channel E1 interface after CRC check and insertion are completed through two CRC check modules; the data blocks with the same time stamp received by the E1 routing protection switching device through the main channel E1 interface / backup channel E1 interface are the same data blocks, and the alignment of the two data channels can be achieved by comparing the labels of the data blocks;

[0019] Two buffer memories are respectively set up for storing the data blocks transmitted by the main channel and the backup channel; the data blocks of each transmission channel are stored in the corresponding buffer memories from low to high addresses in order from large to small according to different time stamps added when the corresponding data blocks are sent; the main channel and the backup channel use the buffer memories with the same structure, and the same address positions of the two buffer memories after storage are completely identical; the data transmitted by the main channel and the backup channel are aligned in the buffer memories; the quality of the main channel and the backup channel data written into the buffer memories is analyzed, and the channel with the best transmission quality is determined, and the data in the buffer memories storing the data of the channel is selected as the output data;

[0020] The data blocks stored in each transmission line are checked for signal loss, alarm indication signal, and frame out-of-sync alarm. At the same time, the frame error and CRC error performance of the data blocks stored in each transmission channel are analyzed and checked, and M.2100 analysis is performed. The data to be selected is determined by a comprehensive judgment method.

[0021] When an alarm occurs during transmission, such as signal loss, alarm indication signal, or frame desynchronization alarm on the main channel, making the data on the channel completely unusable, the data output on the user side only needs to be read and outputted completely from the backup channel data buffer memory RAM, that is, switching to the backup channel to complete the alarm switching;

[0022] If a single bit error occurs in a data block, it becomes a bit error switching, and the device is configured for error level switching.

[0023] As a further solution of the present invention, the E1 routing protection switching device further includes a whole-machine power supply module for supplying power.

[0024] As a further solution of the present invention, the FPGA module includes a transmission channel data performance analysis module, a data fast CRC calculation module, a device ID identification module, a smooth phase-locked loop module, and a channel data alignment module;

[0025] The data fast CRC calculation module is used to detect bit errors in a short time, complete fast error detection and fast channel data switching;

[0026] The channel data alignment module completes the performance analysis of data alarm, bit error, etc. under the condition of short additional delay, and serves as the criterion for channel switching to achieve the purpose of lossless switching of alarm and bit error;

[0027] The smooth phase-locked loop module realizes smooth clock switching and compensation between the main channel and the backup channel;

[0028] The transmission channel data performance analysis module is used to realize real-time alarm, error detection and M.2100 analysis of multi-channel data;

[0029] The device ID identification module is used to implement device identification and channel identification to avoid connection errors.

[0030] The present invention is a protection switching device for improving the reliability of E1 channel transmission of power system stability control and relay protection. The E1 routing protection switching device can realize the E1 lossless switching function. Lossless switching is achieved by increasing the transmission path, providing a spare circuit (redundant circuit), adjusting the propagation delay generated when the signal is transmitted along different paths in the network, performing reception alarm detection and error measurement according to ITU-T recommendations and CRC-4 information blocks, analyzing the transmission quality of signals from different paths online, and then deciding to select one of the two circuits according to the set judgment rules.

[0031] Compared with the prior art, the present invention has the following beneficial effects:

[0032] 1) The E1 route protection switching device of the present invention can switch to another route without damage when any alarm or error of LOS, LOF or AIS occurs in the currently transmitting route.

[0033] 2) The E1 routing protection switching device of the present invention can achieve a two-way delay difference of 32ms, and can compensate for delays of lines with larger delay differences according to application scenarios, ensuring normal use when using different transmission methods (such as optical fiber, satellite, microwave and other systems).

[0034] 3) The additional delay of a single E1 routing protection switching device of the present invention is less than 1.4ms, which is mainly achieved through a data fast CRC calculation module, and the error detection is achieved in a shorter time, without the need for a large amount of cached data, and the additional delay of the device is small.

[0035] 4) The E1 routing protection switching device of the present invention has the function of main channel / backup channel delay test.

[0036] 5) The E1 routing protection switching device of the present invention has a power-off automatic short-circuit protection function. When the device loses power, the user-side E1 interface data can communicate through the main channel or backup channel preset by the device.

[0037] 6) The E1 routing protection switching device of the present invention has multiple data format interfaces, including framed PCM30 / PCM31, PCM30C / PCM31C, unframed 1B2B, 1B4B, CMI, DMI, etc.

[0038] 7) The E1 routing protection switching device of the present invention has a main channel / backup channel connection status identification function. When the main channel / backup channel cross-link error occurs, the device issues a channel connection error alarm.

[0039] 8) The E1 routing protection switching device of the present invention has a channel loopback status detection function. When the channel of the device is looped back (including device local loopback, DDF local loopback, etc.), the device issues a channel loopback alarm.

[0040] 9) The E1 routing protection switching device of the present invention has error performance analysis of user side E1 interface data, main channel E1 interface data, and standby channel E1 interface data. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] Figure 1 Application scenario for E1 routing protection switching equipment;

[0042] Figure 2 This is a schematic diagram of the E1 routing protection switching equipment;

[0043] Figure 3 E1 interface module for E1 routing protection switching equipment;

[0044] Figure 4 FPGA module for E1 routing protection switching equipment;

[0045] Figure 5 It is the sending part of the E1 routing protection switching equipment;

[0046] Figure 6 Fully digital phase-locked loop for E1 routing protection switching equipment;

[0047] Figure 7 Data alignment RAM logic for E1 routing protection switching equipment. DETAILED DESCRIPTION

[0048] The present invention is described in detail below in conjunction with specific embodiments. The embodiments described below are only part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative work are within the scope of protection of the present invention.

[0049] Definitions of Abbreviations and Key Terms:

[0050] E1: Europe's 30-channel pulse code modulation PCM is referred to as E1, with a rate of 2.048Mbit / s.

[0051] PCM: Pulse Code Modulation.

[0052] SDH: Synchronous Digital Hierarchy.

[0053] ITU-T: ITU-T for ITU Telecommunication Standardization Sector, International Telecommunication Union.

[0054] G.740: Synchronous frame structure for 1544, 6312, 2048, 8448 and 44736 Kbit / s series levels.

[0055] M.2100: Performance limits for international PDH digital paths, sections and transmission systems put into service and for maintenance.

[0056] CRC4: Cyclic Redundancy Check 4, is a form of cyclic redundancy check (a method of detecting errors in transmitted data) used on E-1 trunk lines.

[0057] 10e-4: 10 to the negative power of 4, which is a bit error rate of 1 / 10000;

[0058] 10e-6: bit error rate of 10 to the negative sixth power, which is 1 / 1000000 bit error;

[0059] RAM: (Random Access Memory) Random Access Memory.

[0060] LOS: Loss Of Signal, signal lost.

[0061] AIS: Alarm Indication Signal, alarm indication signal.

[0062] DDF: Digital Distribution Frame, digital distribution frame.

[0063] FPGA: Field Programmable Gate Array, field programmable gate array.

[0064] PCM30 / 31: Pulse Code Modulation 30 / 31 voice channels, pulse code modulation 30 / 31 voice channels.

[0065] PCM30C / 31C: Pulse Code Modulation 30C / 31C voice channel, pulse code modulation 30 / 31 voice channel with CRC check.

[0066] HDB3: High Density Bipolar of Order 3 code, third-order high-density bipolar code.

[0067] 1B2B: data encoding format, 1 bit is encoded as 2 bits.

[0068] 1B4B: data encoding format, 1 bit is encoded as 4 bits.

[0069] CMI: Coded Mark Inversion, data encoding format, code inversion code.

[0070] DMI: Data Mask Inversion, data encoding format, data inversion code.

[0071] ID: Identity document, identity identification.

[0072] FSMC: Fleible static memory controller, flexible static storage controller.

[0073] HDMI: High Definition Multimedia Interface, high-definition multimedia interface.

[0074] CRC: Cyclic Redundancy Check, cyclic redundancy check.

[0075] USB: Universal Serial Bus, is an interface standard widely used in computers and their peripheral devices.

[0076] MiniPCIe interface: an interface based on the PCI-E bus. The PCI-E (Peripheral Component Interconnect Express) bus is a high-speed serial computer expansion bus standard.

[0077] SATA: Serial Advanced Technology Attachment, a hard disk interface specification. Example 1

[0078] like Figure 2 As shown, the E1 routing protection switching device includes a user-side E1 interface (see Figure 2 Part 201 of the ), main channel E1 interface (see Figure 2 Part 202 of the ), spare channel E1 interface (see Figure 2 203), FPGA modules (see Figure 2 Part 204 of the ), embedded control units (see Figure 2 Part 205 of the ), network communications and peripheral units (see Figure 2Part 206 of the ), the whole machine power supply module (see Figure 2 207 and 208 of the Regulations).

[0079] The network communication and peripheral unit includes an auxiliary computer interface, an HDMI display interface, a USB keyboard and mouse interface, a MiniPCIE interface, a SATA hard disk interface, and an Ethernet interface.

[0080] The main functions of the embedded control unit are to complete the equipment's working mode settings, alarm collection and display, and communicate with the network and peripheral units.

[0081] The main functions of the network communication and peripheral unit are to communicate with the embedded control unit, obtain the working status of the device, and communicate with the host computer management software through the Ethernet interface.

[0082] The whole machine power supply module is used to supply power. The whole machine power supply adopts -48V dual power supply hot backup power supply, providing +12V, +5V, +3.3V and other working power supplies for each module of the device.

[0083] like Figure 3 As shown, the E1 interface module of the E1 routing protection switching device (see Figure 3 301 of the IEEE 802.11 Standard), which includes user-side E1 interface, main channel E1 interface, and backup channel E1 interface; it has the functions of receiving, sending, loopback control, HDB3 encoding and decoding, clock recovery smoothing, and jitter attenuation of E1 data.

[0084] like Figure 4 As shown in the figure, the FPGA module of the E1 routing protection switching device realizes two main functions: on the one hand, it detects data alarms, frame synchronization processing, CRC check, and rate adaptation from the user side E1 interface, and then inserts the ID and official communication data, and sends them out through the main channel E1 interface and the backup channel E1 interface respectively (see Figure 4 On the other hand, it detects data alarms, frame synchronization processing, CRC check, rate adaptation, RAM data alignment, and switching control from the main channel E1 interface and the backup channel E1 interface, selects a channel of intact data without alarms or bit errors, and sends it out through the user-side E1 interface to achieve lossless data switching (see Figure 4 405, 406, 407, 408 of the Regulations).

[0085] The FPGA module includes a transmission channel data performance analysis module (see Figure 4 401, 405), data fast CRC calculation module (see Figure 4 403 of the ), Device ID Identification Module (see Figure 4Part 406 of the ), smooth phase-locked loop module (see Figure 4 407 of the ), channel data alignment module (see Figure 4 section 408 of the Regulations).

[0086] The data fast CRC calculation module is used to realize bit error detection in a short time, complete fast error detection and fast channel data switching.

[0087] The channel data alignment module completes performance analysis of data such as alarm and bit error under the condition of shorter additional delay, and serves as a criterion for channel switching to achieve the purpose of lossless switching of alarm and bit error.

[0088] The smooth phase-locked loop module realizes smooth clock switching and compensation of the main channel and the standby channel.

[0089] The transmission channel data performance analysis module is used to implement real-time alarm, error detection and M.2100 analysis of multi-channel data.

[0090] The device ID identification module is used to implement device identification and channel identification to avoid connection errors.

[0091] The data processing process of the E1 routing protection switching device is as follows:

[0092] The sending part of the E1 routing protection switching equipment (see Figure 4 401~404 parts) receive the E1 interface data from the user side, realize frame synchronization, decoding, insert time stamp signal, device service contact data, channel ID and CRC check data according to the set data format, form two new PCM31C frames, and send them to the main channel E1 interface and the backup channel E1 interface respectively, completing the transmission of the main channel E1 data and the backup channel E1 data.

[0093] The receiving part of the E1 routing protection switching equipment (see Figure 4 405~408 of the ), receiving data from the main channel E1 interface and the backup channel E1 interface, performing alarm detection, frame synchronization detection, frame error detection, and CRC error detection on the data of the main channel E1 interface and the backup channel E1 interface, extracting the main channel / backup channel time stamp, obtaining the user ID, extracting the device service contact data, and using the clock smoothing phase lock implemented by the full digital phase-locked loop (see Figure 6 601, 602), according to the timing signal of the main channel / backup channel, the data blocks of a specific sequence are stored in the corresponding positions of the RAM (random access memory) (see Figure 7701 and 702 of the main channel), complete the data alignment of the main channel / backup channel, complete the switching of the main channel E1 interface / backup channel E1 interface data and clock through the alarm detection and CRC error detection of the signals from the main channel E1 interface / backup channel E1 interface, select a channel data without alarm and error to be sent out through the user side E1 interface, and realize the lossless switching of user data.

[0094] The following details the steps for automatic switching of E1 routing protection switching equipment without loss:

[0095] The sending part of the E1 routing protection switching equipment includes a time stamp insertion module (see Figure 5 Part 501 of the IEC 60001), ID insertion modules for interconnection and channel identification between devices (see Figure 5 502, 505 parts), a business message insertion module for inserting official communication data between devices (see Figure 5 503, 506) and the CRC check module for CRC check (see Figure 5 Parts 504 and 507 of G.704). The insertion of the time stamp can use certain specific idle time slots of G.704. The insertion of the ID is mainly used for interconnection and channel identification between devices. The IDs of the main channel and the backup channel are different to avoid channel transceiver connection errors and the channels use different transmission media (optical fiber or digital microwave, etc.). Business contact data is mainly used for communication between a pair of devices, device status acquisition, channel delay calculation and mutual control. The data of the inserted time stamp, ID and contact business message is sent to the main channel E1 interface / backup channel E1 interface after CRC verification and insertion through two CRC verification modules. The data block with the same time stamp received by the E1 routing protection switching device through the main channel E1 interface / backup channel E1 interface is the same data block. The alignment of the two data channels can be achieved by comparing the labels of the data blocks.

[0096] Data storage and alignment of the main channel and the backup channel. For the data blocks transmitted by the two transmission channels (main channel and backup channel), two buffer memories (dual-port RAM) are set up for storage (see Figure 7 701 and 702 of the Figure 7As shown, for each data block of each transmission channel, according to the different time stamps added when the corresponding data block is sent, the data blocks are stored in the corresponding buffer memory from low to high addresses in order from large to small, such as from labels 1, 2, 3... to n (n is the storage quantity of the buffer memory, n=65536), and so on. The main channel and the backup channel use the same structure of the buffer memory. Due to the different delays of the two transmission channels, the write operations (write pointers) of the two buffer memories are also different, but the same address positions of the two buffer memories after storage store exactly the same data. The data transmitted by the main channel and the backup channel are aligned in the buffer memory. The present invention performs quality analysis on the main channel and the backup channel data written into the buffer memory, determines the channel with the best transmission quality, and selects the data in the buffer memory storing the data of the channel as the output data.

[0097] The present invention uses a transmission channel data performance analysis module to perform quality analysis on the main channel and standby channel data written into the buffer memory. The quality analysis includes: checking the alarms such as signal loss (LOS), alarm indication signal (AIS), frame loss (LOF) and the like for the data blocks stored in each transmission line, and analyzing and checking the performances such as frame error and CRC error of the data blocks stored in each transmission channel, performing M.2100 analysis, and using a comprehensive judgment method to determine the data to be selected. For example, the weight value of each performance parameter can be set according to the summarized experience or the actual line conditions, and the data transmission quality of each transmission channel can be calculated according to the set weight value, and this can be used as the basis for channel switching.

[0098] When an alarm occurs during transmission, such as LOS (loss of signal), AIS (alarm indication signal), LOF (loss of frame) and other alarms occur on the main channel, making the data of this channel completely unusable, the data output on the user side only needs to be read and output completely from the backup channel data buffer memory RAM, that is, switching to the backup channel. This is the alarm switching process.

[0099] If there is no alarm on the main channel and backup channel signals, but a bit error is detected, for example, there is a bit error in the "7th" block of data on channel 1 (CRC4 bit error), and there is a bit error in the "9th" block of data on channel 2, when the "7th" block of data should be output, the device will switch to channel 2 and read data from the dual-port RAM of channel 2. When the "9th" block of data is output, the device will switch to channel 1 and read data from the dual-port RAM of channel 1. In this way, lossless switching of data is achieved. Since the two channels are two completely independent systems (the current domestic SDH transmission systems are usually two independent systems, with SDH transmission equipment provided by two different manufacturers), the probability of bit errors occurring at the same time is very small, so the probability of bit errors in user protection data is significantly reduced, effectively improving the quality of the transmission line. This is the process of bit error switching.

[0100] If a single bit error occurs in a data block, it is called bit error switching. The device can also be configured for error level switching, that is, when the channel error reaches a certain threshold (10e-4, 10e-6), switching is called error level switching. When the transmission quality of the two transmission channels has certain problems, a channel with relatively better transmission performance is selected. Users can choose bit error switching or level error switching according to the actual line conditions.

[0101] Bit error switching requires rapid judgment and fast switching, and the control of the output data pointer requires very precise control. Error switching only switches the output data RAM, which is a summary without switching. The alarm switching clock must also be switched synchronously. Whether it is error switching or alarm switching, it will affect or damage the output clock. Long-term damage accumulation (under extreme conditions) will cause clock slippage, resulting in deviation of the output RAM pointer. When the deviation increases to a set threshold, the software will make corresponding compensation for the clock by adjusting the all-digital phase-locked loop set by the present invention after judgment, so that the output signal is not affected by frequent switching and caused damage. Example 2

[0102] Figure 1 This is a typical application scenario of E1 routing protection switching equipment. Specifically:

[0103] The first protection device (see Figure 1 101) protection service data, connected to the first E1 routing protection switching device (see Figure 1 The data is processed by framing, adding time stamp, ID, CRC check, etc., and then sent to the optical fiber communication terminal equipment (such as the main channel E1 interface and the backup channel E1 interface) through the user side E1 interface of the 102nd part ... Figure 1 103) for transmission, and at the receiving end (see Figure 1105) is received through the main channel E1 interface and the standby channel E1 interface, and after alarm detection, error detection, time alignment, and switching control, a channel of intact data is selected and output to the second protection device through the user side E1 interface (see Figure 1 108 of the Regulations).

[0104] The advantage of this application is to provide lossless protection channel E1 routing.

[0105] In addition, it should be understood that those skilled in the art should regard the specification as a whole, and the technical solutions in each embodiment may also be appropriately combined to form other implementation methods that can be understood by those skilled in the art.

Claims

1. E1 routing protection switching equipment, characterized by: It includes E1 interface module, FPGA module, embedded control unit, network communication and peripheral unit; The E1 interface module includes a user side E1 interface, a main channel E1 interface, and a standby channel E1 interface; The E1 interface module implements E1 data reception, transmission, loopback control, HDB3 encoding and decoding, clock recovery smoothing, and jitter attenuation; The FPGA module detects data alarms, frame synchronization processing, CRC check, and rate adaptation from the user side E1 interface, and then inserts the ID and official communication data, and sends them out through the main channel E1 interface and the backup channel E1 interface respectively; The FPGA module also detects data alarms, frame synchronization processing, CRC check, rate adaptation, RAM data alignment, and switching control from the main channel E1 interface and the backup channel E1 interface, selects a channel of intact data without alarms or errors, and sends it out through the user side E1 interface to achieve lossless switching of data; The embedded control unit is used to complete the working mode setting of the device, the collection and display of alarms, and communicate with the network and peripheral units; The E1 routing protection switching device lossless automatic switching includes the following steps: The sending part of the E1 routing protection switching device includes a time stamp insertion module, an ID insertion module for interconnection and channel identification between devices, a business message insertion module for inserting official communication data between devices, and a CRC check module for CRC check. The insertion of the time stamp uses certain specific idle time slots of G.704, the insertion of the ID is used for interconnection and channel identification between devices, the IDs of the main channel and the backup channel are different, and the official communication data is used for communication, device status acquisition, channel delay calculation and mutual control between a pair of devices; the data of the inserted time stamp, ID and communication official message are sent to the main channel E1 interface / backup channel E1 interface after CRC check and insertion are completed through two CRC check modules; the data blocks with the same time stamp received by the E1 routing protection switching device through the main channel E1 interface / backup channel E1 interface are the same data blocks, and the alignment of the two data channels can be achieved by comparing the labels of the data blocks; Two buffer memories are respectively set up for storing the data blocks transmitted by the main channel and the backup channel; the data blocks of each transmission channel are stored in the corresponding buffer memories from low to high addresses in order from large to small according to different time stamps added when the corresponding data blocks are sent; the main channel and the backup channel use the buffer memories with the same structure, and the same address positions of the two buffer memories after storage are completely identical; the data transmitted by the main channel and the backup channel are aligned in the buffer memories; the quality of the main channel and the backup channel data written into the buffer memories is analyzed, and the channel with the best transmission quality is determined, and the data in the buffer memories storing the data of the channel is selected as the output data; The data blocks stored in each transmission line are checked for signal loss, alarm indication signal, and frame out-of-sync alarm. At the same time, the frame error and CRC error performance of the data blocks stored in each transmission channel are analyzed and checked, and M.2100 analysis is performed. The data to be selected is determined by a comprehensive judgment method. When an alarm occurs during transmission, such as signal loss, alarm indication signal, or frame desynchronization alarm on the main channel, making the data on the channel completely unusable, the data output on the user side only needs to be read and outputted completely from the backup channel data buffer memory RAM, that is, switching to the backup channel to complete the alarm switching; If a single bit error occurs in a data block, it becomes a bit error switching, and the device is configured for error level switching.

2. The E1 routing protection switching device according to claim 1, characterized in that: The network communication and peripheral unit includes an auxiliary computer interface, an HDMI display interface, a USB keyboard and mouse interface, a MiniPCIE interface, a SATA hard disk interface, and a hard disk power interface.

3. The E1 routing protection switching device according to claim 1, characterized in that: The process of data processing of the E1 routing protection switching device includes the following steps: The sending part of the E1 routing protection switching device receives data from the user side E1 interface, implements frame synchronization, decoding, inserts time stamp signals, device service contact data, channel ID and CRC check data according to the set data format, forms two new PCM31C frames, and sends them to the main channel E1 interface and the backup channel E1 interface respectively, completing the sending of the main channel E1 data and the backup channel E1 data; The receiving part of the E1 routing protection switching device receives data from the main channel E1 interface and the backup channel E1 interface, performs alarm detection, frame synchronization detection, and frame error and CRC error performance detection on the data of the main channel E1 interface and the backup channel E1 interface, extracts the main channel / backup channel time stamp, obtains the user ID, extracts the device service contact data, uses the clock smoothing phase lock implemented by the full digital phase-locked loop, stores the data blocks of a specific sequence to the corresponding positions of the RAM according to the time stamp signal of the main channel / backup channel, completes the data alignment of the main channel / backup channel, completes the switching of the main channel E1 interface / backup channel E1 interface data and clock through the alarm detection and CRC error detection of the signal from the main channel E1 interface / backup channel E1 interface, selects a channel data without alarm and error to be sent out through the user side E1 interface, and realizes the lossless switching of user data.

4. The E1 routing protection switching device according to claim 1, characterized in that: It also includes a whole machine power supply module for power supply.

5. The E1 routing protection switching device according to claim 1, characterized in that: The FPGA module includes a transmission channel data performance analysis module, a data fast CRC calculation module, a device ID identification module, a smooth phase-locked loop module, and a channel data alignment module; The data fast CRC calculation module is used to detect bit errors in a short time, complete fast error detection and fast channel data switching; The channel data alignment module completes the data alarm and error performance analysis under the condition of shorter additional delay, and serves as the criterion for channel switching to achieve the purpose of lossless switching of alarm and error; The smooth phase-locked loop module realizes smooth clock switching and compensation of the main channel and the backup channel; The transmission channel data performance analysis module is used to realize real-time alarm, error detection and M.2100 analysis of multi-channel data; The device ID identification module is used to implement device identification and channel identification to avoid connection errors.

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