CN217237860U - Wisdom orchard soil moisture content monitoring system based on loRa technique - Google Patents

Abstract

The utility model relates to a soil moisture monitoring system for a smart orchard based on LoRa technology. The device communicates with the node aggregation device through the LoRa wireless communication module, and the node aggregation device is used to receive the identification information and data, and check the time information of the identification information and data, and then communicate with the host computer. The above-mentioned upper computer is used to perform statistical analysis on the above-mentioned identification information and data. The utility model is a multi-parameter sensor acquisition device with low power consumption, high precision, high compatibility, good expansibility, stability and reliability, and abundant resources, which effectively solves the core technology of high-precision and low-cost data acquisition in the field of Internet of Things data acquisition. question.

Description

Smart orchard soil moisture monitoring system based on LoRa technology

technical field

The utility model relates to the field of agricultural Internet of things, in particular to an orchard moisture monitoring system.

Background technique

Carrying out the monitoring of soil moisture in farmland can realize timely and appropriate irrigation, effectively solve the problem of agricultural water saving, and achieve the purpose of saving water and increasing production and increasing benefits; with the development of automation technology and communication technology, manual monitoring methods have been completely replaced, and There are many types of highly integrated sensors and measurement signals involved in data acquisition. However, in the field of IoT data acquisition, it has the characteristics of harsh environmental conditions, high acquisition accuracy, high transmission rate, and large data throughput. For this reason, the system is stable and reliable. Security, anti-interference, encrypted data transmission and data storage have become the key issues to be overcome.

The application number is 201710528262.9, and the application name is a low-power soil monitoring system based on the LoRa Internet of Things, including a soil monitoring station group and a remote monitoring service platform. The soil monitoring group includes a main soil monitoring station and multiple data collection from soil monitoring stations The system has problems of low data accuracy, low compatibility, complex operation, and testing in a limited environment. First, there is a lack of a data acquisition system that integrates multi-parameter sensor interface resources, has high sampling accuracy, and is cost-effective; second, the cost of the sensor module of the monitoring object is very high and the system compatibility is poor. Increasing the matching interface level improves the system performance. The overall power consumption cannot meet the low power consumption requirements of the monitoring system; third, the nonlinear sensor used in the monitoring object system is difficult to calibrate, the development and verification cycle is long, and the design workload is large.

At the same time, due to the fact that Gansu mountain orchard covers a large area and the land is barren and arid, the communication reliability, real-time acquisition and system stability of the existing soil moisture system cannot adapt to this situation, and at the same time, it cannot be expanded. , can not meet the practical application needs of remote monitoring in Gansu region, especially for mountain orchards.

To this end, it is necessary to research a multi-parameter sensor acquisition device with low power consumption, high precision, high compatibility, good scalability, stability and reliability, and rich resources, which can effectively solve the core of high-precision and low-cost data acquisition in the field of IoT data acquisition. technical problem.

SUMMARY OF THE INVENTION

The purpose of the utility model is to avoid the deficiencies of the prior art, and to provide a system based on which communication reliability, real-time acquisition and system stability are significantly improved, functions are easily expanded, and the practical application requirements of remote monitoring of mountain orchards can be efficiently met. Smart orchard soil moisture monitoring system based on LoRa technology.

In order to achieve the above-mentioned purpose, the technical scheme adopted by the present utility model is: a kind of intelligent orchard soil moisture monitoring system based on LoRa technology, including distribution and being arranged in the described orchard, for collecting at least two of orchard distribution point identification information and data. Node acquisition device, the node acquisition device is communicated and connected with the node aggregation device through the LoRa wireless communication module, and the node aggregation device is used to receive the identification information and data, and check the identification information and the time information of the data, and then communicate with the node aggregation device. The upper computer is connected for communication, and the upper computer is used to perform statistical analysis on the identification information and data;

The node collection device includes a first sensor for sampling soil moisture and a second sensor for sampling ambient temperature and humidity, and the output ends of the first sensor and the second sensor are respectively connected to the GPIO of the first processor. The input end interface is connected, the described LoRa wireless communication module is integrated on the described first processor, the interface of the radio frequency transmitting end of the LoRa wireless communication module is electrically connected with the GPIO output end interface of the first processor; a solar battery electrically connected to the node collection device;

The node aggregation device includes a radio frequency receiving end of the LoRa wireless communication module, and the radio frequency receiving end of the LoRa wireless communication module is used to transmit the identification information with the radio frequency transmitting end of the LoRa wireless communication module by framing a custom modbus protocol. and collecting data; the radio frequency receiving end of the LoRa wireless communication receiving module is electrically connected to the input end of the second processor, and the second processor passes through the Ethernet interface of the Ethernet PHY chip integrated on the second processor. Communication connection with the host computer.

Further, the first sensor is electrically connected to a signal conditioning circuit, and the signal conditioning circuit is used to convert the 4-20mA current signal output by the first sensor into a 0-3.2V voltage signal; the first processor passes The on-chip 16-bit analog-to-digital converter ADC samples and quantizes the voltage signal;

The signal conditioning circuit includes a non-inverting amplifier U1 and a differential amplifier U2;

Between the signal forward output end and the reverse output end of the interface J1 of the first sensor, a sampling resistor R9 and a filter circuit connected in parallel with the sampling resistor R9 are connected, and the sampling resistor R9 is used to convert the current signal into For the voltage signal, the inverting output terminal of the first sensor is grounded, and is connected to the inverting input terminal of the non-inverting amplifier U1 through the voltage dividing resistor R12, and the output terminal of the non-inverting amplifier U1 is connected to the inverting phase of the non-inverting amplifier U1 through the feedback resistor R11. Input terminal, the non-inverting amplifier U1 is used to output 440-2200mV voltage signal;

The output terminal of the non-inverting amplifier U1 is connected to the inverting input terminal of the differential amplifier U2 through the input loop resistance R6, and the reference voltage 440mV is connected to the non-inverting input terminal of the differential amplifier U2 through the first voltage dividing resistor R7. The non-inverting input terminal is connected to the ground through the second voltage dividing resistor R10 and the third voltage dividing resistor R13 in series; the output terminal of the differential amplifier U2 outputs a voltage of 0-3.2V through the passive RC low-pass filter resistor R8 and the capacitor C3 The output terminal of the differential amplifier U2 is also connected in series to the non-inverting input terminal of the differential amplifier U2 through the second feedback resistor R2 and the first feedback resistor R1 connected in series in sequence.

Further, a first zero-adjusting resistor R3 and a second zero-adjusting resistor R4 are respectively connected between the NC input ports and the NC output ports of the non-inverting amplifier U1 and the differential amplifier U2; The resistance value of the two zero-adjusting resistor R4 is 8 to 12kΩ.

Further, the filter circuit is a first filter capacitor C1 and a second filter capacitor C2 arranged in parallel, the first filter capacitor C1 is 8-12uF, and the second filter capacitor C2 is 0.08-0.12uF; The output end of the passive RC low-pass filter resistor R8 is grounded and filtered through the third filter capacitor C3, and the third filter capacitor C3 is 0.08-0.12uF.

Further, the sampling resistor R9 is 90-110Ω, the balance resistor R5 is 8.8-9.4kΩ, the feedback resistor R11 is 9-11kΩ, the voltage dividing resistor R12 is 98-108kΩ; The loop resistance R6 is 9~11kΩ, the second feedback resistance R2 and the first feedback resistance R1 are 8.8~9.4kΩ, the first voltage dividing resistor R7 is 9~11kΩ, the second voltage dividing The resistor R10 and the second voltage dividing resistor R3 are 8.8-9.4kΩ, and the passive RC low-pass filter resistor R8 is 98-108kΩ.

Further, the second sensor has a control SCL pin and a serial port data SDA pin, and the control SCL pin and the serial port data SDA pin are respectively connected with the first pull-up resistor R14 and the second pull-up resistor R15. the I2C interface pins of the first processor are electrically connected;

The second pull-up resistor R15 is used for pulling down or raising the output signal of the SDA pin of the serial port data of the second sensor during SDA data transmission, the signal is pulled down not less than 30μs, and then raised not less than 30μs; After the second sensor receives the signal of the first processor, the second sensor is used to send 40 bits of data from the high position of the serial port data SDA pin at one time, followed by high humidity, low humidity, high temperature, and low temperature. and check digit, where the check digit is equal to the sum of 8 high humidity bits, 8 low humidity bits, 8 high temperature bits, and 8 low temperature bits.

Further, the radio frequency receiving end of the LoRa wireless communication receiving module has an AUX interface for indicating the working state of the LoRa wireless communication receiving module, and the AUX interface is connected to the 5V voltage through the first resistor R16, and the LoRa wireless communication receives The RXD interface and TXD interface of the radio frequency receiving end of the module are respectively connected with the VOA interface and VIB interface of the digital isolator U4. At the same time, the RXD interface and the TXD interface are connected to 5V through the second pull-up resistor R17 and the third pull-up resistor R18 respectively. voltage connection;

The radio frequency receiving end of the LoRa wireless communication receiving module also has an M0 interface and an M1 interface for switching the transmission, WOR, configuration and deep sleep working modes of the LoRa wireless communication receiving module;

The circuit connection structure of the radio frequency receiving end of the LoRa wireless communication receiving module and the radio frequency transmitting end of the LoRa wireless communication module is the same.

Further, the first resistor R16, the second resistor R17 and the third resistor R18 are 9-11kΩ.

Further, the receiving end of the described LoRa wireless communication receiving module matches the signal of the transmitting end of the LoRa wireless communication receiving module, and both adopt the wireless serial port module E22-400T30D of the SX1268 radio frequency chip of SEMTECH Company; the described digital isolator U4 is a dual Channel digital isolator ADuM1201AR chip.

Further, the model of the first processor and the second processor is STM32H743XI; the model of the second sensor is: AM2315C; the model of the Ethernet PHY chip is: LAN8720A.

The beneficial effects of the utility model are as follows: an automatic monitoring and control system for mountain orchards is constructed based on the LoRa technology, and the STM32H743XI chip is used as the controller to design the soil moisture signal conditioning circuit, the ambient temperature and humidity and the LoRa module interface circuit, as well as the LoRa module configuration and transceiver. Program design, the collection node sends the sampled data regularly, the sink node uses the circular queue to asynchronously parse the received data, and send it to the upper computer for statistical analysis. The design scheme of the orchard soil moisture monitoring system has the advantages of high communication reliability, high real-time acquisition, The advantages of good system stability and easy expansion provide technical support for future LoRa applications.

Description of drawings

Figure 1 is the overall structure diagram of the system;

Figure 2 is the soil moisture sensor conditioning circuit;

Figure 3 is the hardware connection diagram of the AM2315 temperature and humidity sensor;

Figure 4 is the hardware connection diagram of the LoRa module.

In the figure: 1. Node aggregation device; 11. RF receiving end of LoRa wireless communication module; 12. Second processor; 13. Ethernet PHY chip; 2. Node acquisition device; 21. First sensor; 22. Second sensor; 23, the first processor; 24, the radio frequency sending end of the LoRa wireless communication module; 25, the solar battery; 5, the upper computer.

Detailed ways

The principles and features of the present invention will be described below with reference to the accompanying drawings, and the examples are only used to explain the present invention, and are not intended to limit the scope of the present invention.

Embodiment 1: as shown in Fig. 1, Fig. 2, Fig. 3, Fig. 4, a kind of wisdom orchard soil moisture monitoring system based on LoRa technology, including distribution is arranged in described orchard, for collecting orchard distribution point identification information and At least two node collection devices 2 of data, the node collection device 2 communicates with the node aggregation device 1 through the LoRa wireless communication module, and the node aggregation device 1 is used to receive the identification information and data, and proofread the identification The time information of information and data, and then communicates with the host computer 5, and the host computer 5 is used to perform statistical analysis on the identification information and data;

The node collection device 2 includes a first sensor 21 for sampling soil moisture and a second sensor 22 for sampling ambient temperature and humidity. The output ends of the first sensor 21 and the second sensor 22 are respectively connected to the A GPIO input interface of the processor 23 is connected, the LoRa wireless communication module is integrated on the first processor 23, and the interface of the radio frequency transmitting end 24 of the LoRa wireless communication module is connected to the GPIO of the first processor 23. The output port interface is electrically connected; it also includes a solar battery 25 electrically connected to the node collection device 2;

The node aggregation device 1 includes a radio frequency receiving end 11 of the LoRa wireless communication module, and the radio frequency receiving end 11 of the LoRa wireless communication module is used to transmit all data through a self-defined modbus protocol with the radio frequency transmitting end 24 of the LoRa wireless communication module. The identification information and the collected data; the radio frequency receiving end 11 of the LoRa wireless communication receiving module is electrically connected with the input end of the second processor 12, and the second processor 12 is integrated on the second processor 12 through the The Ethernet interface of the Ethernet PHY chip 13 is connected to the upper computer 5 for communication.

As shown in FIG. 2 , the first sensor 21 is electrically connected to the signal conditioning circuit, and the signal conditioning circuit is used to convert the 4-20mA current signal output by the first sensor 21 into a 0-3.2V voltage signal; The first processor 23 samples and quantizes the voltage signal through the on-chip 16-bit analog-to-digital converter ADC; the signal conditioning circuit includes a non-inverting amplifier U1 and a differential amplifier U2; at the interface of the first sensor 21 Between the forward output terminal and the reverse output terminal of the J1 signal, a sampling resistor R9 and a filter circuit connected in parallel with the sampling resistor R9 are connected. The sampling resistor R9 is used to convert the current signal into a voltage signal. The first sensor The inverting output terminal of 21 is grounded and connected to the inverting input terminal of the non-inverting amplifier U1 through the voltage dividing resistor R12. The output terminal of the non-inverting amplifier U1 is connected to the inverting input terminal of the non-inverting amplifier U1 through the feedback resistor R11. The non-inverting amplifier U1 U1 is used to output 440～2200mV voltage signal;

The output terminal of the non-inverting amplifier U1 is connected to the inverting input terminal of the differential amplifier U2 through the input loop resistance R6, and the reference voltage 440mV is connected to the non-inverting input terminal of the differential amplifier U2 through the first voltage dividing resistor R7. The non-inverting input terminal is connected to the ground through the second voltage dividing resistor R10 and the third voltage dividing resistor R13 in series; the output terminal of the differential amplifier U2 outputs a voltage of 0-3.2V through the passive RC low-pass filter resistor R8 and the capacitor C3 The output terminal of the differential amplifier U2 is also connected in series to the non-inverting input terminal of the differential amplifier U2 through the second feedback resistor R2 and the first feedback resistor R1 connected in series in sequence.

A first zero-adjustment resistor R3 and a second zero-adjustment resistor R4 are respectively connected between the NC input ports and the NC output ports of the non-inverting amplifier U1 and the differential amplifier U2; the first zero-adjustment resistor R3 and the second zero-adjustment resistor R3 The resistance value of the resistor R4 is 8-12kΩ.

The filter circuit is a first filter capacitor C1 and a second filter capacitor C2 arranged in parallel, the first filter capacitor C1 is 8-12uF, and the second filter capacitor C2 is 0.08-0.12uF; the passive RC The output end of the low-pass filter resistor R8 is grounded and filtered through the third filter capacitor C3, and the third filter capacitor C3 is 0.08-0.12uF.

The sampling resistor R9 is 90-110Ω, the balance resistor R5 is 8.8-9.4kΩ, the feedback resistor R11 is 9-11kΩ, the voltage dividing resistor R12 is 98-108kΩ; the loop resistance R6 is 9-11kΩ, the second feedback resistor R2 and the first feedback resistor R1 are 8.8-9.4kΩ, the first voltage dividing resistor R7 is 9-11kΩ, the second voltage dividing resistor R10 and The second voltage dividing resistor R3 is 8.8-9.4kΩ, and the passive RC low-pass filter resistor R8 is 98-108kΩ.

As shown in FIG. 3 , the second sensor 22 has a control SCL pin and a serial port data SDA pin, and the control SCL pin and the serial port data SDA pin pass through the first pull-up resistor R14 and the second pull-up respectively. The resistor R15 is electrically connected to the I2C interface pin of the first processor 23;

The second pull-up resistor R15 is used to pull down or raise the output signal of the serial port data SDA pin of the second sensor 22 during SDA data transmission. After the second sensor 22 receives the signal of the first processor 23, the second sensor 22 is used to send 40 bits of data from the serial port data SDA pin high position at one time, followed by humidity high position, humidity low position, temperature High bit, low temperature bit and check digit, where the check digit is equal to the sum of 8 high humidity bits, 8 low humidity bits, 8 high temperature bits, and 8 low temperature bits.

As shown in FIG. 4 , the radio frequency receiving end 11 of the LoRa wireless communication receiving module has an AUX interface for indicating the working state of the LoRa wireless communication receiving module. The AUX interface is connected to the 5V voltage through the first resistor R16, and the The RXD interface and the TXD interface of the radio frequency receiving end 11 of the LoRa wireless communication receiving module are respectively the VOA interface and the VIB interface of the digital isolator U4. At the same time, the RXD interface and the TXD interface pass through the second pull-up resistor R17 and the third The pull-up resistor R18 is connected to the 5V voltage;

The radio frequency receiving end 11 of the LoRa wireless communication receiving module also has an M0 interface and an M1 interface for switching the transmission, WOR, configuration and deep sleep working modes of the LoRa wireless communication receiving module;

The circuit connection structure of the radio frequency receiving end 11 of the LoRa wireless communication receiving module and the radio frequency transmitting end 24 of the LoRa wireless communication module is the same.

The first resistor R16, the second resistor R17 and the third resistor R18 are 9-11kΩ.

The receiving end 11 of the LoRa wireless communication receiving module matches the signal of the transmitting end 24 of the LoRa wireless communication receiving module, both of which use the wireless serial port module E22-400T30D of SEMTECH's SX1268 radio frequency chip; the digital isolator U4 is a dual-channel Digital isolator ADuM1201AR chip. The model of the first processor and the second processor is STM32H743XI; the model of the second sensor 22 is AM2315C; the model of the Ethernet PHY chip 13 is LAN8720A.

In the smart orchard soil moisture monitoring system based on LoRa technology provided by the utility model, the provided soil moisture sensor is that the first sensor 21 outputs a 4-20 mA signal, which is converted into a 0-3.2 V voltage signal by the signal conditioning circuit, and the node acquisition device 2 The voltage signal is sampled and quantified by the on-chip 16-bit ADC of the first processor 23, and the 40-bit data of the first sensor 22 is read through the I2C interface. The data is sent to the node aggregation device 2 using a custom MODBUS protocol package. The node aggregation device 2 uses a circular queue to store the received data in the cache, and the parsed data is sent to the software of the upper computer 5 through the Ethernet PHY chip 13, and the upper computer statistically analyzes the data and stores it in the distributed file storage database MongoDB, so that Users can query historical data, and can also send control commands to acquisition nodes.

The transmission medium of the Ethernet PHY chip 13 is twisted pair, the transmission rate is 10 Mbps, and has the advantages of large data throughput, high transmission rate, strong anti-interference, good scalability, and high cost performance.

The first sensor 21 is a soil moisture sensor, which reflects the real moisture content of various soils by measuring the dielectric constant of the soil. The output signal of the adopted module is 4-20mA, the range is 0-100%, the resolution is 0.1%, and the accuracy is ±3%.

The signal conditioning circuit of the soil moisture sensor is shown in Figure 2. The signal conditioning circuit includes a soil moisture sensor interface J1, a non-inverting amplifier U1, a sampling resistor R9, a first filter capacitor C1, a second filter capacitor C2, a balance resistor R5, a feedback resistor R11, a voltage divider resistor R12, a first zero adjustment resistor R3, Differential amplifier U2, input loop resistor R6, feedback resistor R1, feedback resistor R2, first voltage dividing resistor R7, second voltage dividing resistor R10, third voltage dividing resistor R13, second zero-adjusting resistor R4, filter resistor R8, The third filter capacitor C3.

The soil moisture sensor is the signal positive terminal of the sensor interface J1 of the first sensor 21. The 4-20mA current signal is converted into a voltage signal through the sampling resistor R9. After filtering by the filter capacitors C1 and C2, the balance resistor R5 is used to act on the non-inverting amplifier U1 in the same phase. The input terminal and the output terminal signal are connected to the inverting input terminal of U1 through the feedback resistor R11 and the voltage dividing resistor R12. The corresponding range of the output voltage after U1 non-inverting amplification is 440-2200mV. The first zero-adjusting resistor R3 is used to adjust the input to zero. The output is also zero. The output voltage signal of the non-inverting amplifier U1 acts on the inverting input terminal of the differential amplifier U2 through the input loop resistor R6, feedback resistors R1 and R2, and the reference voltage 440mV passes through the first voltage dividing resistor R7, the second voltage dividing resistor R10, and the third voltage dividing resistor. R13 is connected to the non-inverting input terminal of the differential amplifier U2. The corresponding range of the output voltage of the differential amplifier U2 after differential amplification is 0~3.2V. The second zero-adjusting resistor R4 is used to adjust the output to zero when the input is zero. The output voltage signal of the differential amplifier U2 is filtered through the passive RC low-pass filter resistor R8 and the third filter capacitor C3 and then output.

The model of the second sensor 22 is AM2315C, which is a semiconductor pipeline temperature and humidity sensor of Aosong Company. It is equipped with a special ASIC chip, a MEMS semiconductor capacitive humidity sensing element and a standard temperature sensing element, and has long-term stability. And higher reliability, it can also maintain excellent performance under extremely harsh environmental conditions of high temperature and high humidity. AM2315 C adopts standard IIC interface, the power supply voltage range is 2.2~5.5V, the temperature measurement range is -40~+80℃, the accuracy is ±0.3℃, the humidity measurement range is 0~100%RH, and the accuracy is ±2%RH. The hardware connection of AM2315 temperature and humidity sensor is shown in Figure 3.

In Figure 3, AM2315C mainly communicates through serial port data SDA. In order to transmit data better, the second pull-up resistor R15 is connected. When SDA data is transmitted, SDA is pulled down for no less than 30μs, and then rises for no less than 30μs. Less than 30μs, after receiving the processor signal, the sensor sends 40 bits of data from the SDA high bit first out at one time, followed by humidity high bit, humidity low bit, temperature high bit, temperature low bit and check digit, where check digit = humidity high 8 Bit + Humidity Low 8 Bits + Temperature High 8 Bits + Temperature Low 8 Bits.

The LoRa wireless communication module adopts the wireless serial port module E22-400T30D of SEMTECH's SX1268 radio frequency chip, TTL level output, power supply voltage 5V, compatible with 3.3V and 5V IO interface voltage, operating temperature -40 ~ 85 ℃, supports 0.3k ～62.5kbps data transmission rate, frequency band 410.125～493.125MHz, maximum transmit power 22.0dBm, selectable 10, 13, 17, 22dBm, transmit length 240Byte, selectable 32, 64, 128, 240Byte, buffer capacity 1000Byte, working frequency band 410.125～493.125MHz, receiving sensitivity -147dBm@0.3Kbps, air rate range is 0.3K～62.5Kbps, communication interface is UART, with automatic relay, air wake-up, wireless configuration, carrier monitoring, communication key, packet length setting The fixed-level function supports fixed-point transmission, broadcast transmission, and channel monitoring. Multi-level relay mode can be used for ultra-long-distance communication. The module has longer transmission distance, faster speed, lower power consumption and smaller size.

The model of the RF receiver (11) of the LoRa wireless communication module is SX1268, its working voltage is 5V, and the working voltage of the second processor 12 is 3.3V. In order to match the IO interface levels of the two, a dual-channel digital isolator ADuM1201AR chip is used. , and its hardware circuit is shown in Figure 4.

In Figure 4, the AUX interface is used to indicate the working status of the module, wake up the external MCU, and output a low level during power-on self-test initialization, and can be left floating when not in use. The two interfaces M0 and M1 are used to configure the 4 working modes of the module. When not in use, it can be grounded but not suspended. When M0 is set to 0 and M1 is set to 0, it is the transmission mode. After the user serial port inputs data, the module starts wireless transmission. , when idle, the wireless receiving function is turned on, and the data is received by the serial port TXD output; when M0 is set to 0, and M1 is set to 1, it is in WOR mode, and a certain time wake-up code is automatically added before transmitting, and receiving is equivalent to mode 0; M0 is set to 1, and M1 is set When 0, it is configuration mode, the wireless transceiver function is turned off, and the user can set the register; when M0 is set to 1, M1 is set to 1, it is deep sleep mode, wireless transceiver is turned off, and the module enters deep sleep mode. When entering other working modes, the module reconfigures parameters .

The transmission modes adopted include broadcast transparent transmission, relay networking and WOR fixed-point transmission. When using the broadcast transparent transmission method, both parties of the communication need to have the same rate level, channel and target address or keep the same parameter values. The LoRa data transmission terminal can receive data from all LoRa data transmission terminals under the same rate, channel and target address. For the fault-tolerant processing of the protocol, if the target address of the LoRa data transmission terminal is set as the broadcast address, other LoRa data transmission terminals with the same rate and the same channel can receive the data sent by the LoRa data transmission terminal. When using the WOR fixed-point transmission mode, there are WOR sender and WOR receiver, which supports air wake-up. The WOR sender will automatically increase the wake-up time for a certain period of time before transmitting data. Input data through the serial port, the module will start wireless transmission, and the WOR receiver module will start wireless transmission. The wireless receiving function is turned on, and the wireless data will be output through the serial port TXD pin after receiving the wireless data. When the relay networking mode is adopted, the relay can start to work after switching to the general mode. The relay mode address (ADDH/ADDL) is no longer used as the module address, which corresponds to the forwarding pairing address of the network address NETID. In the relay mode, the relay The network address of the device itself is invalid, it cannot send and receive data, and it cannot perform low-power operation.

When the LoRa wireless communication module transmits or receives data through transparent transmission, the module identifies the specific information of the node, and the module address, network address, transmit power, frequency channel, function code, time information, data and verification data adopt a custom modbus communication protocol. Framing transmission, the framing data is transmitted after being encrypted by AES-128 encryption algorithm, and enters deep sleep mode after transmission is completed in a timed interval mode to reduce system power consumption.

The receiving end 11 of the LoRa wireless communication module uses a circular queue asynchronous analysis method to receive data, stores the received data in the circular queue buffer, and uses the MODBUS protocol to parse the data or instructions.

The monitoring software of the host computer 5 adopts the Pycharm development environment, and designs the host computer monitoring interface in combination with PyQt5, statistically analyzes the data information received from the aggregation node, and stores the data in the database MongoDB of distributed file storage, so as to further query and process historical data. .

The solar battery adopts 12V solar battery module.

The above are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principles of the present invention shall be included in the present invention. within the scope of protection of the utility model.

Claims (10)

1. a smart orchard soil moisture monitoring system based on LoRa technology, is characterized in that, comprises and is arranged in described orchard and is distributed at least two node acquisition devices (2) for collecting orchard distribution point identification information and data, node The acquisition device (2) is communicated with the node aggregation device (1) through a LoRa wireless communication module, and the node aggregation device (1) is used to receive the identification information and data, and to check the time of the identification information and data information, and then communicated with the host computer (5), and the host computer (5) is used to perform statistical analysis on the identification information and data; The node collection device (2) includes a first sensor (21) for sampling soil moisture and a second sensor (22) for sampling ambient temperature and humidity, the first sensor (21) and the second sensor (22) The output terminals of the sensor (22) are respectively connected with the GPIO input terminals of the first processor (23), and the LoRa wireless communication module is integrated and arranged on the first processor (23). The interface of the radio frequency transmitting end (24) is electrically connected with the GPIO output end interface of the first processor (23); further comprising a solar battery (25) electrically connected with the node collection device (2); The node aggregation device (1) includes a radio frequency receiving end (11) of the LoRa wireless communication module, and the radio frequency receiving end (11) of the LoRa wireless communication module is used to communicate with the radio frequency transmitting end (24) of the LoRa wireless communication module. The identification information and the collected data are transmitted by custom modbus protocol framing; the radio frequency receiving end (11) of the LoRa wireless communication receiving module is electrically connected with the input end of the second processor (12), and the second processing The device (12) is communicatively connected to the upper computer (5) through the Ethernet interface of the Ethernet PHY chip (13) integrated on the second processor (12). 2. The smart orchard soil moisture monitoring system based on LoRa technology as claimed in claim 1, wherein the first sensor (21) is electrically connected with a signal conditioning circuit, and the signal conditioning circuit is used to connect the first sensor (21). 21) The output 4-20mA current signal is converted into a 0-3.2V voltage signal; the first processor (23) samples and quantizes the voltage signal through the on-chip 16-bit analog-to-digital converter ADC; The signal conditioning circuit includes a non-inverting amplifier U1 and a differential amplifier U2; Between the forward output terminal and the reverse output terminal of the interface J1 signal of the first sensor (21), a sampling resistor R9 and a filter circuit connected in parallel with the sampling resistor R9 are connected, and the sampling resistor R9 is used to convert the current The signal is converted into a voltage signal, the inverting output terminal of the first sensor (21) is grounded, and is connected to the inverting input terminal of the non-inverting amplifier U1 through the voltage dividing resistor R12, and the balancing resistor R5 is connected to the non-inverting input terminal of the non-inverting amplifier U1 , the output terminal of the non-inverting amplifier U1 is connected to the inverting input terminal of the non-inverting amplifier U1 through the feedback resistor R11, and the non-inverting amplifier U1 is used to output a voltage signal of 440-2200mV; The output terminal of the non-inverting amplifier U1 is connected to the inverting input terminal of the differential amplifier U2 through the input loop resistance R6, and the reference voltage 440mV is connected to the non-inverting input terminal of the differential amplifier U2 through the first voltage dividing resistor R7. The non-inverting input terminal is connected to the ground through the second voltage dividing resistor R10 and the third voltage dividing resistor R13 in series; the output terminal of the differential amplifier U2 outputs a voltage of 0-3.2V through the passive RC low-pass filter resistor R8 and the capacitor C3 The output terminal of the differential amplifier U2 is also connected in series to the non-inverting input terminal of the differential amplifier U2 through the second feedback resistor R2 and the first feedback resistor R1 connected in series in sequence. 3. the wisdom orchard soil moisture monitoring system based on LoRa technology as claimed in claim 2, is characterized in that, is respectively connected with the first adjustment between the NC input port, the NC output port of described non-inverting amplifier U1 and differential amplifier U2. The zero resistance R3 and the second zero adjustment resistor R4; the resistance values of the first zero adjustment resistor R3 and the second zero adjustment resistor R4 are 8-12kΩ. 4. the wisdom orchard soil moisture monitoring system based on LoRa technology as claimed in claim 2 is characterized in that, described filter circuit is the first filter capacitor C1 and the second filter capacitor C2 that are arranged in parallel, and the first filter The capacitor C1 is 8~12uF, and the second filter capacitor C2 is 0.08~0.12uF; the output end of the passive RC low-pass filter resistor R8 is grounded and filtered by the third filter capacitor C3, and the third filter capacitor C3 is 0.08~ 0.12uF. 5. the smart orchard soil moisture monitoring system based on LoRa technology as claimed in claim 2, is characterized in that, described sampling resistance R9 is 90～110Ω, described balance resistance R5 is 8.8～9.4kΩ, described The feedback resistor R11 is 9-11kΩ, the voltage dividing resistor R12 is 98-108kΩ; the loop resistance R6 is 9-11kΩ, the second feedback resistor R2 and the first feedback resistor R1 are 8.8-9.4kΩ, The first voltage dividing resistor R7 is 9-11kΩ, the second voltage-dividing resistor R10 and the second voltage-dividing resistor R3 are 8.8-9.4kΩ, and the passive RC low-pass filter resistor R8 is 98 ~108kΩ. 6. The smart orchard soil moisture monitoring system based on LoRa technology as claimed in claim 1, wherein the second sensor (22) has a control SCL pin and a serial port data SDA pin, and the control SCL leads The pin and the serial port data SDA pin are respectively electrically connected to the I2C interface pin of the first processor (23) through the first pull-up resistor R14 and the second pull-up resistor R15; The second pull-up resistor R15 is used to pull down or raise the output signal of the serial port data SDA pin of the second sensor (22) during SDA data transmission. In 30µs; after the second sensor (22) receives the signal from the first processor (23), the second sensor (22) is used to send 40-bit data from the high-order bit of the serial port data SDA pin at one time, and sequentially It is the high humidity bit, low humidity bit, high temperature bit, low temperature bit and check digit, where the check digit is equal to the sum of 8 high humidity bits, 8 low humidity bits, 8 high temperature bits, and 8 low temperature bits. 7. The smart orchard soil moisture monitoring system based on LoRa technology as claimed in claim 1, wherein the radio frequency receiving end (11) of the LoRa wireless communication receiving module has a function for instructing the LoRa wireless communication receiving module to work. The AUX interface of the state, the AUX interface is connected with the 5V voltage through the first resistor R16, the RXD interface and the TXD interface of the radio frequency receiving end (11) of the LoRa wireless communication receiving module are respectively connected with the VOA interface and VIB interface of the digital isolator U4 At the same time, the RXD interface and the TXD interface are respectively connected to the 5V voltage through the second pull-up resistor R17 and the third pull-up resistor R18; The radio frequency receiving end (11) of the LoRa wireless communication receiving module further has an M0 interface and an M1 interface for switching the transmission, WOR, configuration and deep sleep working modes of the LoRa wireless communication receiving module; The circuit connection structure of the radio frequency receiving end (11) of the LoRa wireless communication receiving module and the radio frequency transmitting end (24) of the LoRa wireless communication module is the same. 8. The soil moisture monitoring system for smart orchards based on LoRa technology as claimed in claim 7, wherein the first resistor R16, the second resistor R17 and the third resistor R18 are 9-11kΩ. 9. The smart orchard soil moisture monitoring system based on LoRa technology as claimed in claim 7, wherein the receiving end (11) of the described LoRa wireless communication receiving module and the transmitting end (24) of the LoRa wireless communication receiving module Signal matching adopts the wireless serial port module E22-400T30D of SX1268 radio frequency chip of SEMTECH Company; the digital isolator U4 is a dual-channel digital isolator ADuM1201AR chip. 10. The smart orchard soil moisture monitoring system based on LoRa technology as described in any one of claims 1-9, is characterized in that, the model of the described first processor and the second processor is STM32H743XI; the second described The model of the sensor (22) is: AM2315C; the model of the Ethernet PHY chip (13) is: LAN8720A.

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