Shipborne cold chain monitoring system based on multi-link compression transmission

Abstract

The present invention discloses a shipborne cold chain monitoring system based on multi-link compression transmission, which relates to the field of cold chain transportation. The system is divided into a shipborne terminal, a shipborne host, a shore-based host and a cloud platform. The transmission from the shipborne terminal to the host can be freely switched according to the strength of the wireless signal. The shipborne host to the cloud platform can choose whether to transmit through Beidou short message compression according to the presence or absence of 5G signals. The test results show that the system can accurately complete data collection and processing, with small system errors, effectively improving the reliability and efficiency of the monitoring system, and has high application value.

Description

Technical Field

[0001] The present invention relates to the field of cold chain transportation, and in particular to a shipborne cold chain monitoring system based on multi-link compression transmission. Background Art

[0002] With the needs of consumption level and social development, real-time and dynamic monitoring of marine cold chain has become a new technical hotspot. Due to the high content of active enzymes in seafood, it is easy to deteriorate during transportation. The whole traceability monitoring of the ship-borne cold chain helps to improve the efficiency and quality of the marine cold chain. Therefore, it is of great significance to build a whole traceability monitoring system for the marine cold chain.

[0003] Scholars have conducted a series of studies on cold chain environmental monitoring. They have designed special wireless sensor networks for special environments, designed a low-power wireless sensor network to address the high energy consumption of cold chain environmental monitoring, proposed an intelligent medical cold chain solution, and provided a system framework, but did not specify how to implement it. Some scholars have made improvements in cold chain logistics routing strategies. Existing technologies have proposed improvement strategies for cold chain logistics monitoring from various aspects. For marine cold chain monitoring, a Beidou short message communication solution based on IoV-BDS has been designed, and the transportation speed and other solutions have been optimized based on the ant colony optimization algorithm. A marine cold chain monitoring solution has been designed based on Beidou, and a wireless monitoring system has been designed based on LoRa.

[0004] Based on the above research, the existing monitoring system has realized the transmission of information, but there are still problems such as unstable information transmission between the terminal and the shipboard host due to the cabin environment, and limited Beidou information transmission bytes. In response to the above problems, this paper realizes the adaptive transmission of information between the terminal and the host and the compressed coding transmission of Beidou information. Summary of the invention

[0005] The purpose of the present invention is to address the above-mentioned shortcomings and propose a shipborne cold chain monitoring system based on multi-link compressed transmission, which includes four parts: a shipborne terminal, a shipborne host, a shore-based host, and a cloud platform. The transmission from the shipborne terminal to the host can be freely switched according to the strength of the wireless signal, and the transmission from the shipborne host to the cloud platform can choose whether to transmit through Beidou short message compression according to the presence or absence of 5G signals.

[0006] The present invention specifically adopts the following technical solutions:

[0007] The shipborne cold chain monitoring system based on multi-link compression transmission includes shipborne terminals, shipborne hosts, shore-based hosts and cloud platforms;

[0008] The shipboard terminal is used to complete the collection and transmission of cabin information, including temperature and humidity sensors, clock modules, communication modules and power modules;

[0009] First, the controller registers are initialized, and then the baud rate of the sensor and wireless communication module is configured. The embedded controller establishes a communication connection with the wireless communication module and the sensor. Then, the controller determines whether the sensor has information. If so, the information is processed and converted into a suitable reporting format.

[0010] There are two modes for reporting data, one is scheduled active reporting and the other is passive reporting. Active scheduled reporting wakes up the device to report according to the set time, and passive reporting requires the shipboard host to issue a command to require the shipboard terminal to report. The reporting process is as follows: when the scheduled time is up and before reporting, all wireless communication modules are in standby state. When reporting, the 433 device is first woken up for reporting. Under normal circumstances, the terminal will receive the confirmation signal from the host. If the shipboard terminal cannot receive the confirmation signal sent back by the shipboard host for a long time, it will switch to LoRa transmission. Similarly, if LoRa transmission is unsuccessful, it will switch to ZigBee transmission until the current transmission is successful, and the next transmission will repeat the previous process.

[0011] At the same time, the shipboard terminal transmits according to the transmission method required by the host. The default resolution set inside the sensor is 12 bits for humidity and 14 bits for temperature. The output data has two bytes, with the high bit in front and the low bit in the back. Before calculating the data, the last two bits of the data need to be set to zero. Taking humidity as an example, formula 1 needs to be used for conversion, and the converted data is transmitted using the designed encoding;

[0012]

[0013] Among them, S RH is the sensor output value, and RH is the real humidity value after conversion. That is, the output data of the sensor needs to be converted to get the real humidity value.

[0014] The shipboard host is used for information aggregation and transmission, including controller, wireless communication module, 5G module and Beidou module; the shipboard host is connected to the cloud platform and terminal. On the one hand, it receives instructions from the host computer and performs corresponding operations, and on the other hand, it receives data from the terminal through various transmission protocols;

[0015] After the system is powered on, the communication module is initialized first, the relevant baud rate parameters are configured, and the communication connection is established. Then the display system and interrupt system are initialized, and the touch screen and timing interrupt system are configured. After the initialization is completed, the signal amplitudes of the three wireless communications are detected. If the signals are normal, the receiving signals are configured according to the upload order of the terminal. If a certain signal strength is detected to be weak, it is switched to a communication network with a strong signal and the terminal is notified. The network with a strong signal is used for uploading. Then the 5G signal is detected. If there is a 5G signal, it is directly uploaded to the cloud platform through the 5G signal. If there is no 5G signal, the data transmission adopts the Beidou short message mode. Then it is judged whether the signal is received correctly. If it is received correctly, it is displayed and stored through the LCD. The alarm is activated when the parameters exceed the standard. If the signal uploaded by the terminal is not received within the specified time, the three communication modes are placed in the receiving state at the same time, waiting for the terminal to change the upload mode to upload data;

[0016] When a command is sent from the remote monitoring center, the shipborne host executes the corresponding command, and the shore-based host is responsible for forwarding the information. When the information is received from the shipborne host via the Beidou short message, it is uploaded to the cloud platform via the 5G signal.

[0017] Preferably, the shipborne terminal is a star network, which is responsible for collecting marine cold chain environmental information and transmitting the information to the shipborne host. There are multiple modes of communication between the two, such as ZigBee, 433M, and LoRa, but only one mode is used for transmission. The switching of transmission mode depends on the amplitude of the signal. It is switched when there is no response from the shipborne host or the signal amplitude is weak. The shipborne host has two communication modes: 5G / BDS. When there is a 5G signal, the information is uploaded to the cloud platform via the 5G signal. When the 5G signal does not exist, the information is transmitted to the shore-based host via Beidou short messages. After receiving the signal, the shore-based host uploads the information to the cloud platform via the 5G signal.

[0018] Preferably, the communication module of the shipborne terminal includes but is not limited to a 433 module, a ZigBee module and a LoRa module, and the embedded controller uses a STM32F103ZET6 single-chip microcomputer.

[0019] The present invention has the following beneficial effects:

[0020] This solution can realize real-time monitoring of marine cold chain information, has simple wiring, and can be applied to a variety of scenarios. It improves the reliability of transmission through multi-protocol transmission from the terminal to the shipboard host, and improves the transmission efficiency from the shipboard host to the cloud platform through coded transmission. The system has good integration performance and can easily establish connections with other host systems. It has good application prospects, and further research can be carried out on the low-power design of the system and artificial intelligence prediction of the quality of marine cold chain goods. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 System overall structure diagram;

[0022] Figure 2 Shipboard terminal system block diagram;

[0023] Figure 3 Shipboard host system block diagram;

[0024] Figure 4 Shipboard terminal system flow chart;

[0025] Figure 5 Onboard host software process. DETAILED DESCRIPTION

[0026] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings and specific embodiments:

[0027] Combination Figure 1 The shipborne cold chain monitoring system based on multi-link compression transmission includes shipborne terminals, shipborne hosts, shore-based hosts and cloud platforms.

[0028] The shipboard terminal is used to complete the collection and transmission of cabin information, such as Figure 2As shown, it includes temperature and humidity sensors, clock modules, communication modules and power modules. Since multiple serial ports are required to communicate with the communication module, the embedded controller uses the STM32F103ZET6 microcontroller. The STM32F103ZET6 has a CPU speed of 72MHz and up to 1MB of flash memory, 6 16-bit timers, each timer has up to 2 PWM channels, 5 USART interfaces, and 3 SPI interfaces, which can fully meet the needs of this design. The 433M module uses the CC1310 chip E70-433MT14S produced by Ebyte Industrial. The module has 8 working modes, a communication distance of up to 1.5KM, an air wake-up function, and supports serial port output of data packet signal strength and environmental noise signal strength. The working mode is configured through the 18-20 pins of the chip, and its 12th and 13th pins are connected to the serial port of the controller for information interaction. The ZigBee module uses the 2.4G networking transparent transmission module TLSR8258, which supports the ZigBee3.0 communication protocol. The current in low-power mode is only 2.5 microamperes. The network can be networked in a multi-level jump manner. The network has self-organization and self-healing functions. Even if one or more nodes are deleted, the network can still self-heal. The module is connected to the embedded controller through the serial port. The LoRa module uses the LG206-LC module, which is developed by Youren Information Technology Co., Ltd. The module integrates node modules, gateways, and cloud platforms. It can achieve end-to-cloud transmission in one step, with low cost. The LG206-LC module can transmit signals at different times without interfering with each other. The maximum transmission distance can reach 5KM, and it has strong anti-interference ability. The cabin environment sensor uses the SHT21 sensor, which is a high-precision humidity and temperature sensor that uses advanced CMOSens technology and has excellent performance and reliability. The humidity measurement accuracy can reach ±2%RH under typical conditions, and the temperature measurement accuracy is ±0.3℃. In addition, the SHT21 sensor has fast response time and low power consumption, making it suitable for applications that require real-time data and long-term operation. The sensor is connected to the embedded controller via an I2C structure.

[0029] like Figure 4 As shown, firstly, the controller registers are initialized, then the baud rate of the sensor and the wireless communication module is configured, the embedded controller establishes a communication connection with the wireless communication module and the sensor, then the controller determines whether the sensor has information, if so, the information is processed and converted into a suitable reporting format;

[0030] There are two modes for reporting data, one is scheduled active reporting and the other is passive reporting. Active scheduled reporting wakes up the device to report according to the set time, and passive reporting requires the shipboard host to issue a command to require the shipboard terminal to report. The reporting process is as follows: when the scheduled time is up and before reporting, all wireless communication modules are in standby state. When reporting, the 433 device is first woken up for reporting. Under normal circumstances, the terminal will receive the confirmation signal from the host. If the shipboard terminal cannot receive the confirmation signal sent back by the shipboard host for a long time, it will switch to LoRa transmission. Similarly, if LoRa transmission is unsuccessful, it will switch to ZigBee transmission until the current transmission is successful, and the next transmission will repeat the previous process.

[0031] At the same time, the shipboard terminal transmits according to the transmission method required by the host. The default resolution set inside the sensor is 12 bits for humidity and 14 bits for temperature. The output data has two bytes, with the high bit in front and the low bit in the back. Before calculating the data, the last two bits of the data need to be set to zero. Taking humidity as an example, formula 1 needs to be used for conversion, and the converted data is transmitted using the designed encoding;

[0032]

[0033] Among them, S RH is the sensor output value, and RH is the real humidity value after conversion. That is, the output data of the sensor needs to be converted to get the real humidity value.

[0034] The shipboard host is used for information aggregation and transmission, including controller, wireless communication module, 5G module and Beidou module, such as Figure 3 The shipboard host connects to the cloud platform and the terminal. On the one hand, it receives the instructions from the host computer and performs corresponding operations. On the other hand, it receives data from the terminal through various transmission protocols.

[0035] The controller is the core of the whole system. The Beidou module and 5G module are responsible for the remote transmission of information. The wireless communication module is used to receive information from the shipboard terminal, and the display module displays the information of each terminal in real time. Among them, the embedded controller and communication module use the same matching modules as the shipboard terminal, which will not be repeated here. The Beidou module is the core of this design. The Beidou short message module M100 series is selected. The modules of this series support two modes: simple command and data transparent transmission. Customers can realize data transmission and reception operations without understanding the Beidou protocol. As a space-based wireless communication method using satellite broadcasting, it contains almost all the characteristics of satellites, such as 24h online, global coverage without dead angles, high security and confidentiality, etc. The module has low transmission delay, encrypted transmission of messages, high confidentiality, small size and low power consumption. The M100 module requires two power supplies, one for MCU power supply and one for PA transmission. Among them, VDD_PA only provides current at the moment of RDSS module transmission, and the instantaneous current can reach 3.5A. In order to ensure the stable operation of the module and improve the success rate of transmission, a large capacitor is placed near the pin for voltage stabilization and filtering, and the serial port of the short message module is connected to the serial port of the controller. At the same time, the module needs to be configured with a Beidou card. The Beidou card used in this design is a civilian level 3 Beidou card, which transmits 78 bytes of short message messages per minute and can transmit Chinese characters, characters and other data. After the module is powered on, the host computer is used to input the card number of the M100 module that receives the short message information into the M100 module that sends the information, and the transparent transmission mode is set. The 5G module uses the RM500U module, which is a 5G R16 high-performance industrial-grade module that supports 5G LAN technology developed by Quectel Communications based on the Unisoc V516 chip platform. It integrates multiple industrial standard interfaces, has a wealth of network protocols, multiple wireless communication standards, and provides rich and easy-to-use API interfaces, large capacity and low latency, providing better support for remote cold chains.

[0036] like Figure 5 As shown, after the system is powered on, the communication module is initialized first, the relevant baud rate parameters are configured, and the communication connection is established. Then the display system and the interrupt system are initialized, and the touch screen and the timing interrupt system are configured. After the initialization is completed, the signal amplitudes of the three wireless communications are detected. If the signals are normal, the receiving signals are configured according to the upload order of the terminal. If a certain signal strength is detected to be weak, it is switched to a communication network with a strong signal and the terminal is notified. The network with a strong signal is used for uploading. Then the 5G signal is detected. If there is a 5G signal, it is directly uploaded to the cloud platform through the 5G signal. If there is no 5G signal, the data transmission adopts the Beidou short message mode, and then it is determined whether the signal is received correctly. If it is received correctly, it is displayed and stored through the LCD. The alarm is activated when the parameters exceed the standard. If the signal uploaded by the terminal is not received within the specified time, the three communication modes are placed in the receiving state at the same time, waiting for the terminal to change the upload mode to upload data;

[0037] When a command is sent from the remote monitoring center, the shipborne host executes the corresponding command, and the shore-based host is responsible for forwarding the information. When the information is received from the shipborne host via the Beidou short message, it is uploaded to the cloud platform via the 5G signal.

[0038] The shipborne terminal is a star network, which is responsible for collecting marine cold chain environmental information and transmitting the information to the shipborne host. There are multiple modes of communication between the two, such as ZigBee, 433M, and LoRa, but only one mode is used for transmission. The switching of transmission mode depends on the amplitude of the signal. It is switched when there is no response from the shipborne host or the signal amplitude is weak. The shipborne host has two communication modes: 5G / BDS. When there is a 5G signal, the information is uploaded to the cloud platform through the 5G signal. When the 5G signal does not exist, the information is transmitted to the shore-based host through the Beidou short message. After receiving the signal, the shore-based host uploads the information to the cloud platform through the 5G signal.

[0039] The communication modules of the shipborne terminal include 433 module, ZigBee module and LoRa module, and the embedded controller uses STM32F103ZET6 microcontroller.

[0040] Beidou level 3 card can send 78 bytes at a time, level 4 card can send 128 bytes at a time, each card has 30 seconds, 1 minute, 5 minutes, and each transmission has a limit. The Beidou level 3 card used in this design, excluding the normal header file standard 6 bytes, only 72 bytes are given to the user, and the shipboard host usually needs to connect to a dozen or even dozens of terminals. In normal mode, each terminal transmission mode is as follows (character format transmission): Terminal number: format is SSS, occupies 3 bytes

[0041] Time: The format is HH:MM:SS, occupying 8 bytes;

[0042] Temperature: The format is TT.M (M=0, 1, 2, ..., 9), occupying 4 bytes;

[0043] Humidity: The format is HH.N (N=0, 1, 2, ..., 9), occupying 4 bytes. A total of 19 bytes.

[0044] Table 1

[0045]

[0046] If the coordinator directly combines and forwards the information of each terminal, only 4 terminal information can be sent at a time, resulting in a huge waste of resources. Therefore, the coordinator information needs to be compressed and encoded for transmission. In cold chain monitoring, it is not necessary to record monitoring information every minute and every second. Generally, it only takes 5 minutes to upload it once, and all terminal information is transmitted at one time. In this scheme, in the Beidou short message receiving information, the first 6 bytes are file header information, byte 0 is the scheme type, which can be A0 or A1, A0 represents scheme 0, A1 represents scheme 1, bytes 1-3 are time information, representing the hours, minutes and seconds of time respectively, byte 4 is the reference temperature information, and the reference temperature is calculated by taking the integer part of the average temperature value of all terminal data in this batch, byte 5 is the reference humidity information, and the remaining 66 bytes are used for the terminal information of this transmission.

[0047] Table 2

[0048]

[0049] In Table 2, the terminal number represents which terminal it is, such as point 1 represents the first terminal of the current system, point 2 represents the second terminal, point N represents the Nth terminal, and n is 1, 2, ..., 33. T1 represents the difference between the temperature of point 1 and the reference temperature in Table 1, H1 represents the difference between the humidity of point 1 and the reference humidity in Table 1, and similarly, TN represents the difference between the temperature of point N and the reference temperature in Table 1, and HN represents the difference between the humidity of point N and the reference humidity in Table 1. In this mode, the difference in temperature values ​​occupies 1 byte, and the first bit of the byte indicates positive and negative, 0 is positive, 1 is negative, and the unit is 0.1 degrees Celsius. The difference range can meet -12.7 to 12.7 degrees Celsius. The same is true for humidity values. A value of -128 is considered an over-limit alarm. From the above principle, it can be seen that Scheme 0 is suitable for environments with relatively consistent cold chain environments and an environment with a deviation from the reference temperature of no more than 12 degrees.

[0050] Scenario 1:

[0051] If the cargo on board is diverse and the cold chain environment changes greatly, Scheme 0 is no longer applicable. At this time, because the cold chain environment does not have very strict requirements on temperature and humidity errors, the temperature is divided into 256 levels from -80 degrees Celsius to +79.5 degrees Celsius, with one level every 0.5 degrees Celsius, from 0 to 255, and the humidity value is divided into 201 levels from 0%-100%RH, corresponding to values ​​0-200, and the remaining values ​​can be specified as alarm information. In mode 1, bytes 4 and 5 in the header file can be unused or transmitted as data bits. Scheme 1 loses some precision, but is suitable for scenarios with large changes in temperature and humidity. At this time, the scheme category value in the header file is A1.

[0052] Table 3 is the terminal monitoring information collected by the ship marine cold chain monitoring system at 22:30:15 on a certain day. The system contains 6 nodes. From the data in the table, the temperature and humidity do not change much. Scheme 0 is used for transmission. After calculation, the integer part of the average temperature is 0 degrees Celsius, and the integer part of the average humidity is 62. The short message header file information is shown in Table 4.

[0053] Table 3

[0054]

[0055] Table 4

[0056]

[0057] The remaining 66 bytes are filled with data as shown in Table 5.

[0058] Table 5

[0059]

[0060] The test included 6 terminal nodes, 1 shipborne host, and 1 shore-based host. The communication adopted Beidou short messages and multi-protocol terminal information collection. The standard measuring instruments used were C-180 / 40 constant temperature and humidity chamber and precision dew point meter. The test results are shown in Table 6.

[0061] Table 6

[0062]

[0063] From the test results, we can see that the temperature indication error is around 0.1 and 0.2 degrees Celsius, the average is around 0.2 degrees Celsius, and the humidity indication error average is around 1.75%RH. The data has a high consistency and fully meets the needs of marine cold chain environment monitoring. Finally, the communication reliability of the equipment is tested. The reliability is measured by the communication success rate, which is defined as:

[0064]

[0065] In the formula, m represents the number of data sent by the terminal, and n represents the number of data received by the cloud platform. The test is carried out outdoors in a simulated marine transportation environment. Data is sent every 5 minutes through random transmission of 5G / Beidou short messages. Since it is impossible to conduct high seas testing, the high seas environment is simulated by plugging and unplugging the 5G module. The 5-day data is tested and analyzed. It can be seen that the communication success rate from the terminal to the shipborne host is above 98% due to the use of multi-protocol transmission. Only individual data is lost during the day. The communication success rate from the shipborne host to the cloud platform is about 96%. Data fluctuations may be caused by weather.

[0066] Of course, the above description is not a limitation of the present invention, and the present invention is not limited to the above examples. Changes, modifications, additions or substitutions made by technicians in this technical field within the essential scope of the present invention should also fall within the protection scope of the present invention.

Claims

1. The shipborne cold chain monitoring system based on multi-link compression transmission is characterized by: Including shipboard terminals, shipboard hosts, shore-based hosts and cloud platforms; The shipboard terminal is used to complete the collection and transmission of cabin information, including temperature and humidity sensors, clock modules, communication modules and power modules; First, the controller registers are initialized, and then the baud rate of the sensor and wireless communication module is configured. The embedded controller establishes a communication connection with the wireless communication module and the sensor. Then, the controller determines whether the sensor has information. If so, the information is processed and converted into a suitable reporting format. There are two modes for reporting data, one is scheduled active reporting and the other is passive required reporting. Active scheduled reporting wakes up the device to report according to the set time, and passive required reporting is issued by the shipboard host to require the shipboard terminal to report. The reporting process is as follows: when the scheduled time is up and before reporting, all wireless communication modules are in standby state. When reporting, first wake up the 433 device to report. Under normal circumstances, the shipboard terminal will receive the confirmation signal from the shipboard host. If the shipboard terminal cannot receive the confirmation signal sent back by the shipboard host for a long time, it will switch to LoRa transmission. Similarly, if LoRa transmission is unsuccessful, it will switch to ZigBee transmission until the current transmission is successful, and the next transmission will repeat the previous process. At the same time, the shipboard terminal transmits according to the transmission method required by the shipboard host. The default resolution set inside the sensor is 12 bits for humidity and 14 bits for temperature. The output data has two bytes, with the high bit in front and the low bit in the back. Before calculating the data, the last two bits of the data need to be set to zero. Taking humidity as an example, formula 1 needs to be used for conversion, and the converted data is transmitted using the designed encoding; Among them, S RH is the sensor output value, and RH is the real humidity value after conversion, that is, the output data of the sensor needs to be converted to get the real humidity value; The shipboard host is used for information aggregation and transmission, including controller, wireless communication module, 5G module and Beidou module; the shipboard host is connected to the cloud platform and the shipboard terminal. On the one hand, it receives instructions from the host computer and performs corresponding operations, and on the other hand, it receives data from the shipboard terminal through a variety of transmission protocols; After the system is powered on, the communication module is initialized first, the relevant baud rate parameters are configured, and the communication connection is established. Then the display system and interrupt system are initialized, and the touch screen and timing interrupt system are configured. After the initialization is completed, the signal amplitudes of the three wireless communications are detected. If the signals are normal, the receiving signals are configured according to the upload order of the shipborne terminal. If a certain signal strength is detected to be weak, it is switched to a communication network with a strong signal and the shipborne terminal is notified. The network with a strong signal is used for uploading. Then the 5G signal is detected. If there is a 5G signal, it is directly uploaded to the cloud platform through the 5G signal. If there is no 5G signal, the data transmission adopts the Beidou short message mode. Then it is judged whether the signal is received correctly. If it is received correctly, it is displayed and stored through the LCD. The alarm is activated when the parameters exceed the standard. If the signal uploaded by the shipborne terminal is not received within the specified time, the three communication modes are placed in the receiving state at the same time, waiting for the shipborne terminal to change the upload mode to upload data; When a command is sent from the remote monitoring center, the ship-borne host executes the corresponding command, and the shore-based host is responsible for forwarding the information. When the information is received from the ship-borne host through the Beidou short message, it is uploaded to the cloud platform through the 5G signal; The shipboard terminal is a star network, which is responsible for collecting marine cold chain environmental information and transmitting the information to the shipboard host. There are multiple modes of communication between the two, such as ZigBee, 433M, and LoRa, but only one mode is used for transmission. The switching of the transmission mode depends on the amplitude of the signal. It is switched when the shipboard host does not respond or the signal amplitude is weak. The shipboard host has two communication modes: 5G / BDS. When there is a 5G signal, the information is uploaded to the cloud platform through the 5G signal. When the 5G signal does not exist, the information is transmitted to the shore-based host through the Beidou short message. After receiving the signal, the shore-based host uploads the information to the cloud platform through the 5G signal; The communication modules of the shipboard terminal include 433 module, ZigBee module and LoRa module, and the embedded controller uses STM32F103ZET6 microcontroller; Beidou-based information transmission adopts a compressed transmission scheme. There are two compressed transmission schemes, and users can choose according to the environment: In this scheme, in the Beidou short message receiving information, the first 6 bytes are file header information, byte 0 is the scheme type, which is A0 or A1, A0 represents scheme 0, A1 represents scheme 1, bytes 1-3 are time information, representing the hours, minutes and seconds of time respectively, byte 4 is the reference temperature information, and the reference temperature is calculated by taking the integer part of the average value of the data temperature values ​​reported by all shipborne terminals this time, byte 5 is the reference humidity information, and the remaining 66 bytes are used for this transmission of shipborne terminal information; scheme 0 is suitable for the situation where the transported goods are relatively consistent and the temperature difference does not exceed 12°, and scheme 1 is suitable for the situation where the transported goods are very different and the temperature difference between cabins exceeds 12°.

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