CN217237860U

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

Info

Publication number: CN217237860U
Application number: CN202220649937.1U
Authority: CN
Inventors: 杜青青
Original assignee: Lanzhou Petrochemical College of Vocational Technology
Current assignee: Lanzhou Petrochemical College of Vocational Technology
Priority date: 2022-03-22
Filing date: 2022-03-22
Publication date: 2022-08-19
Anticipated expiration: 2032-03-22

Abstract

The utility model relates to a wisdom orchard soil moisture content monitoring system based on loRa technique, a serial communication port, set up including distributing in the orchard for two at least node collection system of collection orchard distribution point identification information and data, node collection system assemble the device communication through loRa wireless communication module and node and are connected, the node assemble the device and be used for receiving identification information and data, and proofread the time information of identification information and data, and then be connected with the host computer communication, the host computer be used for right identification information and data carry out statistical analysis. The utility model relates to a low-power consumption, high accuracy, compatible high, the expansibility good, reliable and stable, abundant resource's many parameter sensor collection system effectively solves thing networking data acquisition field hi-accuracy, low-cost data acquisition's core technical problem.

Description

Wisdom orchard soil moisture content monitoring system based on loRa technique

Technical Field

The utility model relates to an agricultural thing networking field, concretely relates to orchard soil moisture content monitoring system.

Background

The monitoring of the soil moisture content of the farmland can be carried out, so that the proper irrigation can be realized in time, the problem of agricultural water conservation can be effectively solved, and the purposes of water conservation, yield increase and benefit increase can be achieved; with the development of automation technology and communication technology, the manual monitoring mode has been thoroughly replaced, and the high-integration sensor and the measurement signal related to data acquisition are of various types, however, in the field of data acquisition of the internet of things, the system has the characteristics of severe environmental conditions, high acquisition precision, high transmission rate, large data throughput and the like, and the stability, reliability, anti-interference performance, data encryption transmission and data storage capacity of the system become key problems to be overcome.

The application number is 201710528262.9, and the application name is low-power consumption soil monitoring system based on loRa thing networking, including soil monitoring station crowd and remote monitoring service platform, the soil monitoring crowd has that data accuracy is low, the compatibility is low, the operation is complicated including a main soil monitoring station and a plurality of data acquisition system from soil monitoring station, test problem in the environment of injecing. Firstly, a data acquisition system which integrates multi-parameter sensor interface resources, and has high sampling precision and high cost performance is lacked; secondly, the cost of a sensor module of a monitored object is very high, the system compatibility is poor, the level of a matching interface is increased, the overall power consumption of the system is improved, and the low power consumption requirement of the monitoring system cannot be met; thirdly, a nonlinear sensor adopted by the system for monitoring the object has high calibration difficulty, long development and verification period and large design workload.

Meanwhile, based on the actual conditions that the land occupation area of the Gansu mountain orchard is large and the land is poor and arid, the communication reliability, the acquisition real-time performance and the system stability of the existing soil moisture system cannot adapt to the conditions, and meanwhile, the function expansion cannot be realized, so that the actual application requirement of remote monitoring of the Gansu mountain orchard can not be met.

Therefore, a multi-parameter sensor acquisition device with low power consumption, high precision, high compatibility, good expansibility, stability, reliability and abundant resources needs to be researched, and the core technical problem of high-precision and low-cost data acquisition in the field of data acquisition of the internet of things is effectively solved.

Disclosure of Invention

An object of the utility model is to avoid prior art's not enough to provide a communication reliability, gather real-time, system stability and all show the improvement, easily function extension, can high-efficiently satisfy hillside orchard remote monitoring's an actual application demand wisdom orchard soil moisture content monitoring system based on loRa technique.

In order to achieve the above purpose, the utility model adopts the following technical scheme: a smart orchard soil moisture monitoring system based on a LoRa technology comprises at least two node acquisition devices which are distributed in an orchard and used for acquiring orchard distribution point identification information and data, wherein the node acquisition devices are in communication connection with a node aggregation device through a LoRa wireless communication module, the node aggregation device is used for receiving the identification information and the data, correcting time information of the identification information and the data and further in communication connection with an upper computer, and the upper computer is used for carrying out statistical analysis on the identification information and the data;

the node acquisition device comprises a first sensor for sampling soil humidity and a second sensor for sampling environmental temperature and humidity, the output ends of the first sensor and the second sensor are respectively connected with the interface of the GPIO input end of a first processor, the LoRa wireless communication module is integrally arranged on the first processor, and the interface of the radio frequency transmitting end of the LoRa wireless communication module is electrically connected with the interface of the GPIO output end of the first processor; the solar energy storage battery is electrically connected with the node acquisition device;

the node aggregation device comprises a radio frequency receiving end of a LoRa wireless communication module, and the radio frequency receiving end of the LoRa wireless communication module is used for framing and transmitting the identification information and the collected data with a radio frequency transmitting end of the LoRa wireless communication module through a user-defined modbus protocol; the radio frequency receiving end of the LoRa wireless communication receiving module is electrically connected with the input end of the second processor, and the second processor is in communication connection with the upper computer through an Ethernet interface of an Ethernet PHY chip integrated on the second processor.

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

the signal conditioning circuit comprises an in-phase amplifier U1 and a differential amplifier U2;

a sampling resistor R9 and a filter circuit connected with the sampling resistor R9 in parallel are connected between a positive output end and a negative output end of a signal of an interface J1 of the first sensor, the sampling resistor R9 is used for converting a current signal into a voltage signal, the negative output end of the first sensor is grounded and is connected to the negative input end of a non-inverting amplifier U1 through a voltage dividing resistor R12, the output end of the non-inverting amplifier U1 is connected to the negative input end of a non-inverting amplifier U1 through a feedback resistor R11, and the non-inverting amplifier U1 is used for outputting a 440-2200 mV voltage signal;

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

Further, a first zero adjusting resistor R3 and a second zero adjusting resistor R4 are respectively connected between the NC input port and the NC output port of the non-inverting amplifier U1 and the NC output port of the differential amplifier U2; the resistance values of the first zero setting resistor R3 and the second zero setting resistor R4 are 8-12 k omega.

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

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

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

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 when the SDA data is transmitted, wherein the signal is pulled down for not less than 30 mus and then raised for not less than 30 mus; after the second sensor receives the signal of the first processor, the second sensor is used for sending 40 bits of data from the pin high position of the serial data SDA at one time, and sequentially comprises a humidity high position, a humidity low position, a temperature high position, a temperature low position and a check position, wherein the check position is equal to the sum of the humidity high 8 position, the humidity low 8 position, the temperature high 8 position and the temperature low 8 position.

Furthermore, the radio frequency receiving end of the LoRa wireless communication receiving module is provided with an AUX interface for indicating the working state of the LoRa wireless communication receiving module, the AUX interface is connected with a 5V voltage through a first resistor R16, an RXD interface and a TXD interface of the radio frequency receiving end of the LoRa wireless communication receiving module are respectively connected with a VOA interface and a VIB interface of the digital isolator U4, and meanwhile, the RXD interface and the TXD interface are respectively connected with the 5V voltage through a second pull-up resistor R17 and a third pull-up resistor R18;

the radio frequency receiving end of the LoRa wireless communication receiving module is also provided with an M0 interface and an M1 interface which are used 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 is the same as that of the radio frequency sending end of the LoRa wireless communication module.

Furthermore, the first resistor R16, the second resistor R17 and the third resistor R18 are 9-11 k omega.

Furthermore, the receiving end of the LoRa wireless communication receiving module is in signal matching with the sending end of the LoRa wireless communication receiving module, and wireless serial port modules E22-400T30D of SX1268 radio frequency chips of SEMTECH company are adopted; the digital isolator U4 is a dual-channel digital isolator ADuM1201AR chip.

Further, the model of the first processor and the second processor is STM32H743 XI; the type of the second sensor is as follows: AM 2315C; the Ethernet PHY chip model is as follows: LAN 8720A.

The beneficial effects of the utility model are that: an automatic hillside orchard monitoring and control system is established based on loRa technique, use STM32H743XI chip as the controller, design soil moisture signal conditioning circuit, environment humiture and loRa module interface circuit, and loRa module configuration and receiving and dispatching programming, collection node regularly sends the sampling data, sink node utilizes the asynchronous analytic acceptance data of circulation queue, and send to the host computer and carry out statistical analysis, this orchard soil moisture content monitoring system's design scheme, it is high to have communication reliability, it is high to gather the real-time, advantages such as system stability is good and easily extension, provide technical support for loRa is used in future.

Drawings

FIG. 1 is a general block diagram of a system;

FIG. 2 is a soil moisture sensor conditioning circuit;

FIG. 3 is a hardware connection diagram of an AM2315 temperature and humidity sensor;

fig. 4 is a hardware connection diagram of the LoRa module.

In the figure: 1. a node aggregation device; 11. a radio frequency receiving end of the LoRa wireless communication module; 12. a second processor; 13. an Ethernet PHY chip; 2. a node acquisition device; 21. a first sensor; 22. a second sensor; 23. a first processor; 24. a radio frequency transmitting end of the LoRa wireless communication module; 25. a solar storage battery; 5. and (4) an upper computer.

Detailed Description

The principles and features of the present invention will be described with reference to the drawings, which are provided for illustration only and are not intended to limit the scope of the invention.

Example 1: as shown in fig. 1, 2, 3 and 4, a smart orchard soil moisture monitoring system based on LoRa technology comprises at least two node acquisition devices 2 which are distributed in an orchard and used for acquiring orchard distribution point identification information and data, wherein the node acquisition devices 2 are in communication connection with a node convergence device 1 through LoRa wireless communication modules, the node convergence device 1 is used for receiving the identification information and the data, correcting time information of the identification information and the data and further in communication connection with an upper computer 5, and the upper computer 5 is used for carrying out statistical analysis on the identification information and the data;

the node acquisition device 2 comprises a first sensor 21 for sampling soil humidity 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 with the interface of the GPIO input end of a first processor 23, 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 electrically connected with the interface of the GPIO output end of the first processor 23; the solar energy collecting device also comprises a solar storage battery 25 electrically connected with the node collecting device 2;

the node convergence device 1 comprises a radio frequency receiving end 11 of a LoRa wireless communication module, wherein the radio frequency receiving end 11 of the LoRa wireless communication module is used for framing and transmitting the identification information and the collected data with a radio frequency transmitting end 24 of the LoRa wireless communication module through a user-defined modbus protocol; 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 in communication connection with the upper computer 5 through an ethernet interface of an ethernet PHY chip 13 integrated on the second processor 12.

As shown in fig. 2, the first sensor 21 is electrically connected to a signal conditioning circuit, and the signal conditioning circuit is configured to convert a 4-20 mA 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 comprises an in-phase amplifier U1 and a differential amplifier U2; a sampling resistor R9 and a filter circuit connected in parallel with the sampling resistor R9 are connected between a positive output end and a negative output end of a signal at an interface J1 of the first sensor 21, the sampling resistor R9 is used for converting a current signal into a voltage signal, the negative output end of the first sensor 21 is grounded and is connected to the negative input end of a non-inverting amplifier U1 through a voltage dividing resistor R12, the output end of the non-inverting amplifier U1 is connected to the negative input end of a non-inverting amplifier U1 through a feedback resistor R11, and the non-inverting amplifier U1 is used for outputting a 440-2200 mV voltage signal;

A first zero setting resistor R3 and a second zero setting resistor R4 are respectively connected between the NC input port and the NC output port of the non-inverting amplifier U1 and the differential amplifier U2; the resistance values of the first zero setting resistor R3 and the second zero setting resistor R4 are 8-12 k omega.

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

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

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

the second pull-up resistor R15 is used for pulling down or raising the output signal of the serial port data SDA pin of the second sensor 22 during SDA data transmission, wherein the signal is pulled down for not less than 30 mus and then raised for not less than 30 mus; after the second sensor 22 receives the signal of the first processor 23, the second sensor 22 is configured to send 40 bits of data from the serial data SDA pin high bit at a time, which are sequentially humidity high bit, humidity low bit, temperature high bit, temperature low bit and check bit, where the check bit is equal to the sum of the humidity high 8 bit, the humidity low 8 bit, the temperature high 8 bit, and the temperature low 8 bit.

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 a voltage of 5V through a first resistor R16, an RXD interface and a TXD interface of the radio frequency receiving end 11 of the LoRa wireless communication receiving module are respectively connected to the VOA interface and the VIB interface of the digital isolator U4, and meanwhile, the RXD interface and the TXD interface are respectively connected to the voltage of 5V through a second pull-up resistor R17 and a 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 mode 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 is the same as that of the radio frequency sending end 24 of the loRa wireless communication module.

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

The receiving end 11 of the LoRa wireless communication receiving module is in signal matching with the sending end 24 of the LoRa wireless communication receiving module, and wireless serial port modules E22-400T30D of SX1268 radio frequency chips of SEMTECH company are adopted; the digital isolator U4 is a dual-channel digital isolator ADuM1201AR chip. The model of the first processor and the model of the second processor are STM32H743 XI; the types of the second sensor 22 are: AM 2315C; the Ethernet PHY chip 13 is: LAN 8720A.

The utility model provides a wisdom orchard soil moisture content monitoring system based on loRa technique, the soil moisture sensor that provides is for first sensor 21 output 4 ~ 20mA signals for 0 ~ 3.2V voltage signal through signal conditioning circuit conversion output, node collection system 2 adopts 16 bits ADC sampling quantization this voltage signal in the 23 pieces of first treater, read first sensor 22's 40 bit data through the I2C interface, the UART interface communicates with the radio frequency transmitting terminal of loRa wireless communication module, adopt self-defined MODBUS agreement group package with the data collection to send to node convergence device 2. The node converging device 2 stores the received data into a cache by adopting a circular queue, the analyzed data is sent to the software of the upper computer 5 through the Ethernet PHY chip 13, and the upper computer counts and analyzes the data and stores the data into a database MongoDB stored in a distributed file, so that a user can inquire historical data conveniently and can also send a control command to a collection node.

The transmission medium of the ethernet PHY chip 13 is a twisted pair, and the transmission rate is 10Mbps, so the ethernet PHY chip has the advantages of high data throughput, high transmission rate, strong interference immunity, good expansibility, high cost performance, and the like.

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 4-20 mA, the range is 0-100%, the resolution is 0.1%, and the precision is +/-3%.

The signal conditioning circuitry of the soil moisture sensor is shown in fig. 2. The signal conditioning circuit comprises a soil humidity 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 dividing resistor R12, a first zero adjusting resistor R3, a differential amplifier U2, an input loop resistor R6, a feedback resistor R1, a feedback resistor R2, a first voltage dividing resistor R7, a second voltage dividing resistor R10, a third voltage dividing resistor R13, a second zero adjusting resistor R4, a filter resistor R8 and a third filter capacitor C3.

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

The second sensor 22 is an AM2315C model, is a semiconductor pipeline type temperature and humidity sensor of the olson company, is internally provided with an ASIC chip, an MEMS semiconductor capacitive humidity sensing element and a standard temperature sensing element, has long-term stability and higher reliability, and can maintain excellent performance even under extreme severe high-temperature and high-humidity environmental conditions. The AM2315C adopts a standard IIC interface, the power supply voltage range is 2.2-5.5V, the temperature measurement range is-40 to +80 ℃, the precision is +/-0.3 ℃, the humidity measurement range is 0-100% RH, and the precision is +/-2% RH. The AM2315 temperature and humidity sensor is hardwired as shown in fig. 3.

In fig. 3, AM2315C mainly communicates through serial data SDA, so as to better transmit data, a second pull-up resistor R15 is connected, when the SDA transmits data, the SDA is pulled down for no less than 30 μ s, and then is raised for no less than 30 μ s, after receiving a signal from the processor, the sensor sends 40 bits of data at first from the SDA high bit at a time, which are humidity high bit, humidity low bit, temperature high bit, temperature low bit and check bit in sequence, where the check bit is humidity high 8 bits + humidity low 8 bits + temperature high 8 bits + temperature low 8 bits.

The LoRa wireless communication module adopts a wireless serial port module E22-400T30D of an SX1268 radio frequency chip of SEMTECH company, TTL level output, power supply voltage of 5V, IO interface voltage compatible with 3.3V and 5V, working temperature of-40-85 ℃, data transmission rate supporting 0.3K-62.5 Kbps, frequency band 410.125-493.125 MHz, maximum transmitting power of 22.0dBm, selectable 10, 13, 17 and 22dBm, transmitting length of 240Byte, selectable 32, 64, 128 and 240Byte, buffer capacity of 1000Byte, working frequency band 410.125-493.125 MHz, receiving sensitivity of-147 dBm @0.3Kbps, air speed range of 0.3K-62.5 Kbps, communication interface of UART subpackage length setting and the like, has functions of automatic relaying, air wireless configuration, carrier monitoring, communication key, UART subpackage length setting and the like, and supports fixed point transmission, broadcast transmission, channel monitoring, and multi-stage transmission distance can be adopted during ultra-long distance communication, and the multi-stage transmission module is farther, the speed is faster, the power consumption is lower, and the volume is littleer.

The model of a radio frequency receiving end (11) of the LoRa wireless communication module is SX1268, the working voltage thereof is 5V, 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 adopted, and the hardware circuit thereof is shown in fig. 4.

In fig. 4, the AUX interface is used to indicate the working state of the module, wake up the external MCU, and output a low level during the initialization period of power-on self-test, which may be suspended when not in use. The two interfaces M0 and M1 are used for configuring 4 working modes of the module, and can be grounded but not suspended when not used, wherein M0 is set to 0, and M1 is set to 0 and is a transmission mode, after data is input by a user serial port, the module starts wireless transmission, and when the module is idle, a wireless receiving function is turned on, and TXD output of a data serial port is received; when M0 is set to 0, M1 is set to 1, the mode is WOR mode, a certain time wake-up code is automatically added before transmission, and the receiving is equal to the mode 0; when M0 is set to 1 and M1 is set to 0, the wireless transceiving function is closed for the configuration mode, and a user can set a register; when M0 is set to 1 and M1 is set to 1, the deep sleep mode is set, wireless transceiving is turned off, the deep sleep mode is entered, and when other working modes are entered, the module reconfigures parameters.

The adopted transmission modes comprise broadcast transparent transmission, relay networking and WOR fixed point transmission modes. When the broadcast transparent transmission mode is adopted, the communication parties need the same rate grade, channel and target address or the parameter values are kept consistent, the LoRa data transmission terminals can receive data sent by all the LoRa data transmission terminals under the same rate, channel and target address, the fault tolerance processing of a protocol is needed, and if the target address of the LoRa data transmission terminal is set as a 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 a WOR fixed-point transmission mode is adopted, a WOR sending party and a WOR receiving party support air awakening, awakening time of a certain time can be automatically increased before the WOR sending party transmits data, data is input through a serial port, a module can start wireless transmission, a wireless receiving function of a WOR receiving party module is turned on, and the WOR receiving party module can be output through a serial port TXD pin after receiving the wireless data. When a relay networking mode is adopted, the relay can start working by switching to a general mode, a relay mode address (ADDH/ADDL) is not used as a module address, but is respectively corresponding to a forwarding pairing address of a network address NETID, and in the relay mode, the network address of the relay is invalid, so that data cannot be sent and received, and low-power-consumption operation cannot be carried out.

The method comprises the steps that specific information of a module identification node is sent or received by the LoRa wireless communication module in a transparent transmission mode, a module address, a network address, transmitting power, a frequency channel, a function code, time information, data and check data are subjected to framing transmission by adopting a user-defined modbus communication protocol, framing data are transmitted after being encrypted by adopting an AES-128 encryption algorithm, and the framing data enter a deep sleep mode after being transmitted in a timing interval mode to reduce system power consumption.

Receiving end 11 of LoRa wireless communication module the received data adopts the asynchronous analysis mode of the circular queue, stores the received data to the circular queue for caching, and adopts the MODBUS protocol to analyze the data or the instruction.

The monitoring software of the upper computer 5 adopts a Pycharm development environment, an upper computer monitoring interface is designed by combining PyQt5, data information received from a sink node is subjected to statistical analysis, and data are stored in a database MongoDB stored in a distributed file so as to further inquire and process historical data.

The solar storage battery adopts a 12V solar storage battery module.

The above description is only for the preferred embodiment of the present invention, and is not intended to limit the present invention, and any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention should be included within the protection scope of the present invention.

Claims

1. The intelligent orchard soil moisture monitoring system based on the LoRa technology is characterized by comprising at least two node acquisition devices (2) which are distributed in an orchard and used for acquiring orchard distribution point identification information and data, wherein the node acquisition devices (2) are in communication connection with a node convergence device (1) through LoRa wireless communication modules, the node convergence device (1) is used for receiving the identification information and the data, correcting time information of the identification information and the data and then in communication connection with an upper computer (5), and the upper computer (5) is used for carrying out statistical analysis on the identification information and the data;

the node acquisition device (2) comprises a first sensor (21) for sampling soil humidity 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 with the interface of the GPIO input end of a first processor (23), a LoRa wireless communication module is integrally arranged on the first processor (23), and the interface of a radio frequency transmitting end (24) of the LoRa wireless communication module is electrically connected with the interface of the GPIO output end of the first processor (23); the solar energy collecting device is characterized by also comprising a solar storage battery (25) electrically connected with the node collecting device (2);

the node convergence device (1) comprises a radio frequency receiving end (11) of a LoRa wireless communication module, wherein the radio frequency receiving end (11) of the LoRa wireless communication module is used for framing and transmitting the identification information and the collected data with a radio frequency transmitting end (24) of the LoRa wireless communication module through a user-defined modbus protocol; the radio frequency receiving end (11) of the LoRa wireless communication receiving module is electrically connected with the input end of a second processor (12), and the second processor (12) is in communication connection with the upper computer (5) through an Ethernet interface of an Ethernet PHY chip (13) integrated on the second processor (12).

2. The intelligent orchard soil moisture monitoring system based on the LoRa technology is characterized in that the first sensor (21) is electrically connected with a signal conditioning circuit, and the signal conditioning circuit is used for converting a 4-20 mA 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 a processor on-chip 16-bit analog-to-digital converter (ADC);

a sampling resistor R9 and a filter circuit connected with the sampling resistor R9 in parallel are connected between a positive output end and a negative output end of an interface J1 signal of the first sensor (21), the sampling resistor R9 is used for converting a current signal into a voltage signal, the negative output end of the first sensor (21) is grounded and is connected to the negative input end of a non-inverting amplifier U1 through a voltage dividing resistor R12, a balance resistor R5 is connected to the non-inverting input end of the non-inverting amplifier U1, the output end of the non-inverting amplifier U1 is connected to the negative input end of the non-inverting amplifier U1 through a feedback resistor R11, and the non-inverting amplifier U1 is used for outputting 440-2200 mV voltage signals;

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

3. The intelligent orchard soil moisture monitoring system based on the LoRa technology is characterized in that a first zero setting resistor R3 and a second zero setting resistor R4 are connected between NC input ports and NC output ports of the in-phase amplifier U1 and the differential amplifier U2 respectively; the resistance values of the first zero setting resistor R3 and the second zero setting resistor R4 are 8-12 k omega.

4. The intelligent orchard soil moisture monitoring system based on the LoRa technology is characterized in that the filter circuit comprises a first filter capacitor C1 and a second filter capacitor C2 which are arranged in parallel, the first filter capacitor C1 is 8-12 uF, and the second filter capacitor C2 is 0.08-0.12 uF; the output end of the resistor R8 of the passive RC low-pass filter is grounded and filtered through a third filter capacitor C3, and the third filter capacitor C3 is 0.08-0.12 uF.

5. The intelligent orchard soil moisture monitoring system based on the LoRa technology as claimed in claim 2, wherein the sampling resistor R9 is 90-110 Ω, the balance resistor R5 is 8.8-9.4 k Ω, the feedback resistor R11 is 9-11 k Ω, and the voltage dividing resistor R12 is 98-108 k Ω; the loop resistor R6 is 9-11 k omega, the second feedback resistor R2 and the first feedback resistor R1 are 8.8-9.4 k omega, the first divider resistor R7 is 9-11 k omega, the second divider resistor R10 and the second divider resistor R3 are 8.8-9.4 k omega, and the passive RC low-pass filter resistor R8 is 98-108 k omega.

6. The LoRa technology based smart orchard soil moisture monitoring system according to claim 1, wherein the second sensor (22) has a control SCL pin and a serial data SDA pin, the control SCL pin and the serial data SDA pin being electrically connected to the I2C interface pin of the first processor (23) through a first pull-up resistor R14 and a second pull-up resistor R15, respectively;

the second pull-up resistor R15 is used for pulling down or raising an output signal of a serial port data SDA pin of the second sensor (22) during SDA data transmission, wherein the signal is pulled down for not less than 30 mus and then raised for not less than 30 mus; after the second sensor (22) receives the signal of the first processor (23), the second sensor (22) is used for sending 40 bits of data from the pin high position of the serial data SDA at one time, and sequentially comprises a humidity high position, a humidity low position, a temperature high position, a temperature low position and a check position, wherein the check position is equal to the sum of the humidity high 8 position, the humidity low 8 position, the temperature high 8 position and the temperature low 8 position.

7. The intelligent orchard soil moisture monitoring system based on the LoRa technology is characterized in that a radio frequency receiving end (11) of the LoRa wireless communication receiving module is provided with an AUX interface used for indicating the working state of the LoRa wireless communication receiving module, the AUX interface is connected with a voltage of 5V through a first resistor R16, an RXD interface and a TXD interface of the radio frequency receiving end (11) of the LoRa wireless communication receiving module are respectively connected with a VOA interface and a VIB interface of a digital isolator U4, and meanwhile, the RXD interface and the TXD interface are respectively connected with the voltage of 5V through a second pull-up resistor R17 and a third pull-up resistor R18;

the radio frequency receiving end (11) of the LoRa wireless communication receiving module is also provided with an M0 interface and an M1 interface which are used for switching the transmission, WOR, configuration and deep sleep working modes of the LoRa wireless communication receiving module;

the radio frequency receiving end (11) of the LoRa wireless communication receiving module is identical to the circuit connection structure of the radio frequency sending end (24) of the LoRa wireless communication module.

8. The intelligent orchard soil moisture monitoring system based on the LoRa technology is characterized in that the first resistor R16, the second resistor R17 and the third resistor R18 are 9-11 k omega.

9. The intelligent orchard soil moisture monitoring system based on the LoRa technology is characterized in that a receiving end (11) of the LoRa wireless communication receiving module is in signal matching with a sending end (24) of the LoRa wireless communication receiving module, and wireless serial port modules E22-400T30D of SX1268 radio frequency chips of SEMTECH company are adopted; the digital isolator U4 is a dual-channel digital isolator ADuM1201AR chip.

10. The intelligent orchard soil moisture monitoring system based on the LoRa technology as claimed in any one of claims 1 to 9, wherein the first processor and the second processor are of the type STM32H743 XI; the type of the second sensor (22) is as follows: AM 2315C; the Ethernet PHY chip (13) has the following model: LAN 8720A.