Explosion-proof communication ad hoc network system for oil cave depot

Abstract

The invention relates to an explosion-proof communication ad hoc network system for an oil cave depot. The explosion-proof communication ad hoc network system comprises terminal equipment, a relay base station and a five-mode mixed signal processing system, the five-mode mixed signal processing system comprises a double-time-slot separation module, a five-mode conversion processing module and an encryption feedback unit. According to the invention, the five-system signal decoding is integrated on one chip, so that the defects caused by multi-chip integration are counteracted while the crossed interconnection of the five-system signals is met; the distribution of the explosion-proof relay base stations is based on a power attenuation rule, so that communication can cover the whole oil cave depot, the safety requirement of 5W low power can be met, the safety power is lower than that of the national standard, and the explosion-proof safety is improved. A high-gain antenna array and a low-loss feeder line system can break through the attenuation limitation of a rock concrete and metal hole body multi-turn path, and the comprehensive coverage of explosion-proof communication is realized.

Description

Technical Field

[0001] The present invention relates to the field of oil bunker communications, in particular to an explosion-proof communication ad hoc network system for oil bunkers. Background Art

[0002] A large amount of oil and gas resources are stored in oil caverns, and their communications need to meet the national standard explosion-proof safety requirements. In addition, most of my country's oil caverns are located in tunnels in mountainous areas. It is currently difficult to achieve communication and intercom in any area of ​​the oil caverns, as well as inside and outside the oil caverns.

[0003] Currently, two-way radios use PDT, DMR, and PDR. PDR, in particular, utilizes encrypted communication. Therefore, direct communication between two-way radios of different standards is impossible. Furthermore, these standards cannot interoperate with analog signals (FM / AM) or public network signals (4G / 5G). Traditional solutions employ a separate design, where each standard uses a corresponding chip to process the signal. This results in multiple chip loads, making terminal devices larger and more power-hungry. Switching between standards requires hardware reconfiguration, increasing latency. Furthermore, the separation of analog and digital signal processing chains leads to noise coupling, resulting in poor call quality.

[0004] Therefore, the present invention proposes a communication ad hoc network system that not only meets the explosion-proof safety requirements, but also can cover the oil caverns and realize clear communication in multiple modes of interaction. Summary of the Invention

[0005] The purpose of this application is to provide an explosion-proof communication ad hoc network system for oil caves, aiming to solve the problems existing in the prior art.

[0006] The present application provides an explosion-proof communication ad hoc network system for a fuel storage bunker, including: Terminal equipment, including explosion-proof walkie-talkies supporting PDT, DMR, PDR, and analog signal transmission, public network terminals supporting 4G / 5G signal transmission, and positioning terminals supporting positioning; relay base stations; and five-mode hybrid signal processing systems. The five-mode hybrid signal processing system includes a dual-time-slot separation module, a five-mode conversion processing module, and an encryption feedback unit, and implements five-mode hybrid signal processing according to the following method: S1, the terminal device transmits a dual-slot mixed signal which is separated into time slot 1: control signaling and time slot 2: service data by the bistable separation circuit of the dual-slot separation module; the time slot allocation weight is dynamically adjusted according to the priority; S2, using the FPGA programmable logic chip to sequentially separate the signal into the standby state signaling, the transceiver control signaling, and the positioning signaling; S3: Identify five-mode signals and separate them by standard signature code. The FPGA has a built-in standard signature library for the five standard signals, identifies the five standard signals, and assists in AI classification. The classification results are weighted voted with the signature code matching results. S4. The five separated digital signals are decoded and converted into analog signals through the five-mode conversion processing module, achieving full compatibility and cross-communication of the five digital signals. The five-mode conversion processing module includes a protocol conversion hardware bridge with integrated five-mode protocol hard decoding logic. S5. Dynamically distribute the power of the five analog signals by weight, establish a cross-connection matrix and a voice / data mapping relationship between the five modes, and obtain a fused signal. The cross-connection matrix is ​​shown in the following formula:

[0007] Where αij is the mapping weight from system i to j, and fi(t) is the time slot / frequency band allocation function; S6. The fused signal is fed back to the explosion-proof relay base station through dual channels. Channel one is the original RF channel transmitted after time slot reorganization, and channel two is the encrypted channel transmitted after encryption by the encryption feedback unit.

[0008] The peeling process in step S2 includes: Phase 1: Physical layer stripping; a sliding window correlator based on the preamble 0x55AA uses a hardware matched filter to synchronously separate the standby state signaling, while preserving the original signal stream in a dual-port RAM buffer; Phase 2: Protocol layer stripping; relying on the FPGA's built-in SM4 dedicated logic unit, the SM4 national secret algorithm is used to decrypt the signaling payload and parse the transmitted and received control signals; the CRC-16 parallel check circuit is used to verify the Beidou / GPS positioning signaling; Phase 3: Application layer stripping; pipeline operation of protocol parsing and data output is implemented through the "ping-pong buffer"; positioning signaling parsing includes: Beidou RDSS protocol parsing and GPS protocol parsing.

[0009] The characteristic code of the standard PDT is 0xAA55+device ID; the characteristic code of the standard DMR is 0x75557755+time slot number; the characteristic code of the standard PDR is a pseudo-random sequence; the characteristic code of the analog signal is the envelope fluctuation rate + zero-crossing rate threshold; the characteristic code of the public network signal is the ZC sequence + NAS layer signaling hash value.

[0010] The hard decoding logic for PDT is time-slot interleaved TDMA hard demodulation, decoding into a G.711 analog waveform; the hard decoding logic for DMR is time-slot interleaved TDMA hard demodulation, decoding into 32-bit parallel matching logic; the hard decoding logic for PDR is custom frequency hopping spread spectrum demodulation, with the key loaded through the DSP, decoding into an FSK baseband signal; the hard decoding logic for analog signals is digital orthogonal demodulation and dynamic AGC, decoding into band-limited filtering; the hard decoding logic for public network signals is OFDM symbol synchronization and FFT hard acceleration, decoding into POTS interface signals.

[0011] The encryption feedback unit is configured with AES-256 encryption algorithm and SM4 national encryption algorithm.

[0012] The explosion-proof relay base station establishes a transmission channel through a four-dimensional handshake link, which includes wireless, optical fiber, network cable and POC. The explosion-proof relay base station is equipped with a low-power 5W transmitter and a Yagi antenna array.

[0013] According to the law of signal power attenuation, when the transmitter power is 5W, the distance between explosion-proof relay base stations in the oil cave is 800 meters, and the explosion-proof relay base stations are set at the corners of each channel of the oil cave in a chain distribution.

[0014] There are five explosion-proof relay base stations, four of which are located at the corners of the two cave passages, and one is located outside the cave to connect to the adjacent explosion-proof relay base stations inside the cave and the oil depot office area outside the cave.

[0015] The gain of the Yagi antenna is 13 dB, the main lobe points to the adjacent base station, and the spatial diversity gain is 5 dB.

[0016] The present invention has the following beneficial effects: It integrates five signal decoding standards into a single chip, meeting the cross-connection requirements of the five standards while offsetting the drawbacks of multi-chip integration. The distribution of explosion-proof relay base stations is based on power attenuation patterns, enabling communication coverage throughout the oil cavern while also meeting the safety requirement of a low power of 5W, lower than the national standard safety power, thus enhancing explosion-proof safety. A high-gain antenna array and low-loss feeder system overcome the attenuation limitations of the multi-turn path of rock concrete and metal caverns, achieving comprehensive explosion-proof communication coverage. DETAILED DESCRIPTION

[0017] The following will be combined with the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0018] An explosion-proof communication ad hoc network system for oil storage bunkers, comprising: Terminal equipment, including explosion-proof walkie-talkies supporting PDT, DMR, PDR, and analog signal transmission, public network terminals supporting 4G / 5G signal transmission, and positioning terminals supporting positioning; relay base stations; and five-mode hybrid signal processing systems. The five-mode hybrid signal processing system includes a dual-time-slot separation module, a five-mode conversion processing module, and an encryption feedback unit, and implements five-mode hybrid signal processing according to the following method: S1. The terminal device transmits a dual-slot mixed signal, which is separated by the dual-slot separation module's bistable separation circuit into Time Slot 1: control signaling (waiting / transmitting and receiving instructions) and Time Slot 2: service data (voice / positioning information). A service type identification state machine is pre-set in the FPGA, and the time slot allocation weight is dynamically adjusted based on the 3-bit priority identification code in the signaling header.

[0019] The dual-time-slot separation module is preferably an FPGA XC7K325T chip.

[0020] The priority classification rules are as follows: the highest priority is safety control commands, including oil pump emergency stop, combustible gas concentration exceeding standard warning, and explosion-proof access control; the second highest priority is real-time monitoring data, including tank level / temperature / pressure sensor data (sampling rate ≥ 10Hz); the normal priority is device status logs, including periodic reporting data such as battery power and signal strength. For example: 3'b111: slot_ratio = 9:1 / / Emergency commands exclusively occupy the time slot; 3'b110: slot_ratio = 7:3 / / Real-time monitoring data priority; default: slot_ratio = 5:5 / / Ordinary data is evenly distributed.

[0021] S2. The signal is stripped out of the standby state signaling, the receiving and sending control signaling, and the positioning signaling in sequence through the FPGA programmable logic chip.

[0022] Phase 1: Physical layer stripping; a sliding window correlator (window width = 16 bits) based on the preamble 0x55AA uses a hardware matched filter to synchronously separate the standby state signaling (fixed length 24 bits), while preserving the original signal stream through the dual-port RAM buffer.

[0023] Phase 2: Protocol layer stripping; relying on the FPGA's built-in SM4 dedicated logic unit (throughput ≥ 1Gbps), the SM4 national encryption algorithm is used to decrypt the signaling payload (the key is dynamically issued by the security chip) to parse the sending and receiving control signals.

[0024] Uses a CRC-16 parallel check circuit (polynomial: 0x1021) to check BeiDou / GPS positioning signaling. A retransmission request is triggered if the check fails.

[0025] Phase 3: Application layer stripping (asynchronous processing); protocol parsing and data output pipeline operation is implemented through the "ping-pong buffer"; positioning signaling parsing includes: Beidou RDSS protocol parsing: extracting latitude, longitude, elevation, and UTC time; GPS protocol parsing: extract GGA sentences in NMEA-0183 format.

[0026] Positioning signaling extraction is based on an improved LDPC error correction algorithm, compensating positioning errors to ±3m. Traditional LDPC algorithms have high bit error rates in long code blocks (such as Beidou's 78-byte frames). This new method dynamically adjusts the parity check matrix weights to adapt to the multipath interference environment of oil depots. In combination with the positioning data redundancy of the Beidou RDSS protocol (such as timestamps and elevation information), prior information is introduced during the decoding phase to aid error correction and reduce positioning drift.

[0027] Error Compensation Mechanism: Utilizing a Kalman filter fusion algorithm, the system fuses LDPC error-corrected positioning data with data from inertial sensors (such as accelerometers) to suppress transient noise. This compensation reduces positioning error from ±10m (original GPS) to ±3m, meeting the safety monitoring requirements of oil depots.

[0028] S3: Identify five-mode signals and separate them by standard signature code. The identification strategy for the five-mode signals is signature code matching and AI-assisted decision-making. The FPGA has a built-in standard signature library for the five standard signals, which identifies the five standard signals and assists in AI classification. The classification results are weighted voting with the signature code matching results.

[0029] The standard feature library is shown in Table 1. This library uses FPGA multi-channel parallel matching to improve recognition speed (single-frame processing time ≤ 50 μs). Preamble matching and AI classification results are weighted and voted to ensure classification accuracy ≥ 95%.

[0030] Table 1 Design rules for signature codes of five signal standards

[0031] In the table, dynamic range compression for analog signal recognition uses the μ-law companding algorithm (compression ratio = 2:1). For public network signal recognition, 4G / 5G signals use ZC sequence detection to identify the physical cell ID (PCI). The public network protocol stack uses the LTE-Uu interface to parse NAS layer signaling.

[0032] AI-assisted decision-making is achieved by deploying a lightweight CNN model (input: signal time-frequency diagram, output: standard classification probability) through the FPGA's built-in convolution accelerator (peak computing power = 4TOPS). Model quantization: 8-bit fixed-point (accuracy loss <1%).

[0033] S4. The five separated digital signals are decoded separately and converted into analog signals uniformly through the five-analog conversion processing module, realizing full compatibility and cross-communication of the five digital signals.

[0034] The five-mode conversion processing module includes: 1. RF Front-End: The RF front-end utilizes the parallel connection of the ADI AD9361 software-defined RF chip and the TI CC1310 narrowband transceiver, combined with a band-adaptive impedance matching network and an FPGA-controlled MOS switch array (32 channels). This achieves a full-band standing wave ratio (VSWR) of less than 1.5, supporting full frequency coverage from 0.1 to 6 GHz. The RF front-end utilizes a broadband zero-IF architecture and integrates a 6 GHz voltage-controlled oscillator (VCO) and a programmable filter bank.

[0035] 2. Protocol Conversion Hardware Bridge: Five-mode protocol hardware decoding logic (PDT / DMR / PDR / public network / analog) is integrated within the FPGA (Xilinx Zynq UltraScale+), as shown in Table 2. A unified symbol mapping interface (16-bit I / Q data stream) and dynamic routing switches enable zero-latency switching (≤5μs). Five-mode signal cross-connection can be handled on a single chip, simplifying chip count and reducing footprint (<15mm²).

[0036] Table 2 Five-mode protocol hard decoding logic and decoding targets

[0037] In addition, the protocol conversion hardware bridge also includes ADC / DAC chips and DSP chips, which achieve zero-latency direct connection between the ADC / DAC and the FPGA through the dual-channel JESD204B interface, dual-channel synchronous transmission (12.5Gbps×2), and eliminate synchronization header redundancy through sub-frame interleaving technology, increasing the effective bandwidth utilization to 98%. LVDS differential pairs (PCB trace impedance 100Ω±5%) support automatic equalization compensation (pre-emphasis +5dB). The dynamic reconfigurable SerDes link connects the FPGA and DSP, breaking the bandwidth bottleneck of the traditional serial bus. On the FPGA side: 8 groups of GTH transceivers (16.3Gbps / channel) are integrated, supporting protocol adaptation (SRIO / PCIe / Ethernet); on the DSP side: configured in RapidIO endpoint mode, microsecond-level time slot allocation is achieved through the priority preemptive scheduling algorithm, and the transmission protocol can be automatically selected according to the data stream type (control / payload): Control instructions: low latency mode (RapidIO short packet, CRC16 checksum).

[0038] Data payload: High throughput mode (10G Ethernet jumbo frames, LDPC error correction).

[0039] 3. Mixed-Signal Cross-Intercommunication Bus: Builds a cross-chip data channel based on the RapidIO protocol, connecting the AD9361 (JESD204B interface), CC1310 (SPI high-speed mode), and analog demodulator (NE612 quadrature output), supporting multi-standard signal frame reassembly and priority arbitration.

[0040] 4‌Full-mode power supply and noise suppression‌: Adopting a multi-stage hybrid power supply network, through ripple cancellation circuit (ripple <3mV) and adaptive ground plane segmentation technology, it eliminates digital / analog signal crosstalk (SNR improvement ≥8dB).

[0041] Power supply: ADC / DAC: Independent LDO power supply (1.0V core voltage, 1.8V I / O), ripple <5mV. FPGA: Multi-phase Buck-Boost power supply (0.85V-1.2V dynamic adjustment), supporting DVFS (Dynamic Voltage Frequency Scaling). DSP: Digitally adjustable PMU (±1% accuracy), receiving FPGA load status instructions via the EMIF bus. When the FPGA detects that the DSP algorithm load exceeds 80%, it automatically increases the DSP voltage (1.0V to 1.1V) and locks the clock frequency.

[0042] While parsing the physical layer frames, the FPGA pushes channel quality information (CQI) to the DSP via RapidIO, enabling the DSP to pre-calculate the spectrum allocation matrix (predicting timeslot occupancy > 90%), enabling parallel decoding and dynamic resource allocation. JESD204B interface data is written directly to the FPGA's block RAM (BRAM), bypassing the DDR controller via the AXI-Stream protocol, reducing latency to 2μs (compared to ≥10μs with traditional solutions), achieving zero-copy data transmission.

[0043] S5. Dynamically distribute the power of the five analog signals by weighted distribution, establish a cross-connection matrix and a voice / data mapping relationship between the five modes, and obtain a fused signal.

[0044] The dynamic range of the output analog signal in step S4 is 60dB, and the weighting formula is as follows:

[0045] Among them, V ref is the reference voltage (corresponding to 60dB dynamic range), V in is the input voltage, V out is the output voltage. The dynamic range of the analog signal after weighted compression is 30dB.

[0046] The cross-connection matrix is ​​shown as follows:

[0047] where α ij is the mapping weight from system i to j (0≤α≤1), f i(t) Assign function to time slot / frequency band.

[0048] The mapping relationship is shown in Table 3.

[0049] Table 3 Voice / data mapping relationship

[0050] S6. The fused signal is fed back to the explosion-proof relay base station through dual channels. Channel one is the original RF channel transmitted after time slot reorganization, and channel two is encrypted by the encryption feedback unit and transmitted to the encryption channel. The encryption feedback unit is configured with AES-256 encryption algorithm and SM4 national encryption algorithm.

[0051] The above process can achieve the synchronous reception of analog signals (FM) and PDT digital signals in the oil depot environment, and convert them into 4G signals through the cross-communication interface and transmit them back to the control center, with a bit error rate (BER): <10 -6 (PDT / 4G intercommunication mode), adjacent channel suppression: >70dB (6GHz band).

[0052] The explosion-proof relay base station establishes a transmission channel via a four-way handshake link (wireless, optical fiber, Ethernet cable, and Point-of-Call). Signals are transmitted via a 5W transmitter (operating current ≤ 1.5A) using an adaptive power algorithm. A 13dB Yagi antenna array (35° horizontal beamwidth, 50Ω ± 5% impedance) is installed on the explosion-proof relay station.

[0053] The four-way handshake dynamically selects the optimal path (wireless / fiber / network cable / POC) based on real-time channel quality (SNR, bit error rate). The remaining links serve as hot standby. Wireless (UHF band) is the default primary link and supports mobile terminal access. Fiber is forced to switch for high-priority data (such as explosion-proof alarms). Network cable / POC (Power over Cable) serves as a backup link, activated only if the primary link is interrupted.

[0054] The primary link transmits at full power (5W). The backup link maintains a low-power heartbeat signal (0.1W) and only transmits link status detection frames.

[0055] The power adaptive algorithm formula is as follows:

[0056] Among them, P base =2W, is the basic transmission power (meeting explosion-proof safety requirements); ΔP is the power adjustment range (0-3W); PL ref is the reference path loss (100dB); PL max is the maximum path loss; K p is the proportional control gain (0.5), which is dynamically adjusted (PID control) according to the feedback bit error rate e(t); PL(d) is the real-time path loss (dB), calculated as:

[0057] Where d is the distance in km and f is the frequency in MHz.

[0058] If PL(d)>PL ref , increase ΔP proportionally.

[0059] If e(t)>10 -3 , trigger K p Closed-loop adjustment to suppress power fluctuations.

[0060] Explosion-proof power constraint: Total power P tx ≤5W, when exceeding the limit, the frequency is forced to be reduced (QPSK→BPSK).

[0061] Path loss compensation verification: Transmitter parameters: Transmit power: 5W (37dBm).

[0062] Antenna gain: 13dB (Yagi array), main lobe pointing toward the adjacent base station, azimuth angle adjustable by ±15°.

[0063] Spatial diversity gain: 5dB (2-channel receive diversity).

[0064] Path Loss Compensation: Total gain = P tx +G tx +G rx −PL(d)≥18dB Example calculation (distance 1km, frequency 400MHz):

[0065] Total gain = 37dBm + 13dB + 5dB − 80dB = −25dBm (not up to standard, requires relay compensation).

[0066] Relay deployment strategy: Plan to deploy explosion-proof base stations every 500-800 meters. Based on a minimum distance of 500 meters, ensure a segment loss of PL(0.5) of 74 dB. After compensation, the value is −25 + 13 + 5 = −7 dBm (which meets the standard).

[0067] The oil depot where the ad hoc network is located has a symmetrical, double-C shape, consisting of two caverns, each 800 meters long, 50 meters wide, and 15 meters high. The rock-concrete structure accounts for over 60% of the structure, while the metal structure accounts for over 30%. Five relay base stations were deployed in a chain formation to accommodate the terrain. Four were placed at the corners of the two parallel C-shaped tunnels, ensuring full coverage within the caverns. One was deployed on the side of the cavern outside the caverns to provide network communication for the outdoor oil depot office area. The five base stations are connected via UHF wireless links with a bandwidth of 25kHz or 12.5kHz. Base stations 1, 3, and 5 are connected via single-mode armored fiber links with a splice loss of ≤0.1dB. Base stations 2 and 4 are connected via a shielded Cat6A network cable with a transmission rate of 1Gbps. The five base stations achieve group session synchronization via public IP (latency compensation ≤50ms). After testing, the end-to-end delay for voice is less than or equal to 150ms, for data is less than or equal to 300ms, and the bit error rate is less than or equal to 10 -6 The positioning update rate is 1Hz (Beidou B1C+GPS L1 dual-frequency).

[0068] Coverage performance verification: the receiving level at the cave entrance is -68dBm, with a signal-to-noise ratio of 22dB; the middle oil storage area is -73dBm, with a signal-to-noise ratio of 19dB; the deepest maintenance area is -81dBm, with a signal-to-noise ratio of 15dB.

[0069] The invention's explosion-proof multi-mode terminal intercom + 5W relay transmitter + self-organizing network multi-dimensional non-sensing full-tunnel roaming automatic switching + high-gain antenna array + low-loss feeder system breaks through the attenuation limitation of rock concrete + metal cave multi-turn path and provides full explosion-proof communication coverage for the entire cave.

[0070] The above embodiments are not limitations of the present invention. Unless otherwise clearly specified and limited, the terms "setting", "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be a connection between the two components. For ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances. The present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the scope of the technical solution of the present invention also fall within the scope of protection of the present invention. In addition, the technical features involved in the different embodiments of the present application described above can be combined with each other as long as they do not conflict with each other.

[0071] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above and that the present invention can be implemented in other specific forms without departing from the spirit or essential characteristics of the present invention. Therefore, the embodiments should be considered in all respects as exemplary and non-restrictive.

Claims

1. An explosion-proof communication ad hoc network system for oil storage, characterized in that: include: Terminal equipment, including explosion-proof walkie-talkies supporting PDT, DMR, PDR, and analog signal transmission, public network terminals supporting 4G / 5G signal transmission, and positioning terminals supporting positioning; relay base stations; and five-mode hybrid signal processing systems. The five-mode hybrid signal processing system includes a dual-time-slot separation module, a five-mode conversion processing module, and an encryption feedback unit, and implements five-mode hybrid signal processing according to the following method: S1, the terminal device transmits a dual-slot mixed signal which is separated into time slot 1: control signaling and time slot 2: service data by the bistable separation circuit of the dual-slot separation module; the time slot allocation weight is dynamically adjusted according to the priority; S2, using the FPGA programmable logic chip to sequentially separate the signal into the standby state signaling, the transceiver control signaling, and the positioning signaling; S3: Identify five-mode signals and separate them by standard signature code. The FPGA has a built-in standard signature library for the five standard signals, identifies the five standard signals, and assists in AI classification. The classification results are weighted voted with the signature code matching results. S4. The five separated digital signals are decoded and converted into analog signals through the five-mode conversion processing module, achieving full compatibility and cross-communication of the five digital signals. The five-mode conversion processing module includes a protocol conversion hardware bridge with integrated five-mode protocol hard decoding logic. S5. Dynamically distribute the power of the five analog signals by weight, establish a cross-connection matrix and a voice / data mapping relationship between the five modes, and obtain a fused signal. The cross-connection matrix is ​​shown in the following formula:

2. Among them α ij is the mapping weight from format i to j, f i(t) Allocate functions for time slots / frequency bands; S6. The fused signal is fed back to the explosion-proof relay base station through dual channels. Channel one is the original RF channel transmitted after time slot reorganization, and channel two is the encrypted channel transmitted after encryption by the encryption feedback unit.

3. The oil storage explosion-proof communication ad hoc network system according to claim 1 is characterized in that: The peeling process in step S2 includes: Phase 1: Physical layer stripping; a sliding window correlator based on the preamble 0x55AA uses a hardware matched filter to synchronously separate the standby state signaling, while preserving the original signal stream in a dual-port RAM buffer; Phase 2: Protocol layer stripping; relying on the FPGA's built-in SM4 dedicated logic unit, the SM4 national secret algorithm is used to decrypt the signaling payload and parse the transmitted and received control signals; the CRC-16 parallel check circuit is used to verify the Beidou / GPS positioning signaling; Phase 3: Application layer stripping; pipeline operation of protocol parsing and data output is implemented through the "ping-pong buffer"; positioning signaling parsing includes: Beidou RDSS protocol parsing and GPS protocol parsing.

4. The oil storage explosion-proof communication ad hoc network system according to claim 1 is characterized in that: The characteristic code of the standard PDT is 0xAA55+device ID; the characteristic code of the standard DMR is 0x75557755+time slot number; the characteristic code of the standard PDR is a pseudo-random sequence; the characteristic code of the analog signal is the envelope fluctuation rate + zero-crossing rate threshold; the characteristic code of the public network signal is the ZC sequence + NAS layer signaling hash value.

5. The oil storage explosion-proof communication ad hoc network system according to claim 1 is characterized in that: The hard decoding logic for PDT is time-slot interleaved TDMA hard demodulation, decoding into a G.711 analog waveform; the hard decoding logic for DMR is time-slot interleaved TDMA hard demodulation, decoding into 32-bit parallel matching logic; the hard decoding logic for PDR is custom frequency hopping spread spectrum demodulation, with the key loaded through the DSP, decoding into an FSK baseband signal; the hard decoding logic for analog signals is digital orthogonal demodulation and dynamic AGC, decoding into band-limited filtering; the hard decoding logic for public network signals is OFDM symbol synchronization and FFT hard acceleration, decoding into POTS interface signals.

6. The oil storage explosion-proof communication ad hoc network system according to claim 1 is characterized in that: The encryption feedback unit is configured with AES-256 encryption algorithm and SM4 national encryption algorithm.

7. The oil storage explosion-proof communication ad hoc network system according to claim 1 is characterized in that: The explosion-proof relay base station establishes a transmission channel through a four-dimensional handshake link, which includes wireless, optical fiber, network cable and POC. The explosion-proof relay base station is equipped with a low-power 5W transmitter and a Yagi antenna array.

8. The oil storage explosion-proof communication ad hoc network system according to claim 6 is characterized in that: According to the law of signal power attenuation, when the transmitter power is 5W, the distance between explosion-proof relay base stations in the oil cave is 800 meters, and the explosion-proof relay base stations are set at the corners of each channel of the oil cave in a chain distribution.

9. The oil storage explosion-proof communication ad hoc network system according to claim 7 is characterized in that: There are five explosion-proof relay base stations, four of which are located at the corners of the two cave passages, and one is located outside the cave to connect to the adjacent explosion-proof relay base stations inside the cave and the oil depot office area outside the cave.

10. The oil storage explosion-proof communication ad hoc network system according to claim 8, characterized in that: The gain of the Yagi antenna is 13 dB, the main lobe points to the adjacent base station, and the spatial diversity gain is 5 dB.

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