Agricultural Internet of Things acquisition terminal based on LoRa-WiFi dual-mode communication

Abstract

The utility model belongs to the technical field of agricultural Internet of Things acquisition terminals, and discloses an agricultural Internet of Things acquisition terminal based on LoRa-WiFi dual-mode communication, which comprises a main control module, a LoRa module, a TYPE-C circuit, an LDO circuit, a CH340C chip, an automatic downloading circuit and an RS485 communication interface circuit. And the main control module is provided with two CPU (Central Processing Unit) cores, operates at an adjustable clock frequency of 80-240MHz, and is provided with a plurality of GPIO (General Purpose Input / Output) pins for communicating with and controlling external equipment. According to the utility model, the LoRa technology and the WiFi technology are integrated, so that the cost of network deployment and operation can be reduced, independent networks do not need to be established and maintained for different application scenes respectively, the network deployment is more flexible and convenient, a proper communication technology can be selected according to actual requirements and environmental conditions, and the communication efficiency is improved. The low power consumption characteristic of LoRa helps to reduce energy consumption, the efficient data transmission of WiFi helps to reduce the idle time of equipment, and the combination of LoRa and WiFi helps to realize a more energy-saving network environment.

Description

TECHNICAL FIELD

[0001] The utility model relates to the technical field of agricultural internet of things collection terminal, especially based on LoRa-WiFi dual mode communication's agricultural internet of things collection terminal. BACKGROUND

[0002] The current development of internet of things technology requires increasing number, coverage range and multi-scene adaptation of communication equipment, such as city environment monitoring, tobacco planting and other application scenarios. The existing data collection terminal usually adopts single WiFi communication, which is single in communication mode and limited in communication range, and cannot meet the diversified communication needs and application scenarios. Therefore, it is an urgent problem to design flexible and efficient, safe and energy-saving LoRa-WiFi dual mode communication node.

[0003] Wi-Fi network technology is a wireless communication technology based on IEEE802.1b standard, commonly known as wireless broadband, which can work in 2.4GHZ and 5GHz frequency bands. There are many competitive technologies in the field of wireless local area network (WLAN), however, Wi-Fi-based positioning usually wins more attention because it can provide higher accuracy in urban areas with multiple low-cost Wi-Fi access points (APs) densely arranged. Wi-Fi technology can be used in indoor and outdoor environments, but it is more cost-effective to use in indoor environments. The normal Wi-Fi working range is about 100m, but due to the influence of factors such as transmission power size and environmental interference, the indoor positioning range of Wi-Fi is generally 10m, and the outdoor range is about 100m. The field area is wide, and the distance far exceeds 100m, and it is not easy to deploy many AP devices. At the same time, LoRa has emerged in recent years as a new communication technology for the Internet of Things. LoRa often uses star-shaped network, and the gateway is connected to the terminal node in a star shape, but the terminal node is not bound to a unique gateway. On the contrary, the uplink data of the terminal node can be sent to multiple gateways. In theory, users can realize flexible networking through Mesh, point-to-point or star-shaped network protocol and architecture. LoRa is very suitable for the needs of internet of things fragmentation, low cost, and large connection due to its low power consumption, long transmission distance, flexible networking and other characteristics, and is widely deployed in smart communities, smart homes and buildings, smart meters, smart agriculture, smart logistics and other vertical industries, with broad prospects. LoRa communication transmission distance can reach 5km-15km, which can perfectly compensate for the disadvantages of WiFi communication. The combination of the two can meet different needs in the application of agricultural internet of things in multiple scenarios and improve the device capability.

[0004] Traditional network deployment is often limited to a single communication technology, while the combination of WiFi + LoRa breaks this limit and organically combines short-distance high-speed communication with long-distance low-power communication. At the same time, there is an innovation in network architecture, and the present patent proposes a multi-level communication network architecture, in which WiFi is responsible for high-speed data transmission in a local area, and LoRa is responsible for wide-area coverage and low-power device connection.

[0005] As for the current network technology, there is no case of combining WiFi and LoRa, therefore, we propose an agricultural Internet of Things collection terminal based on LoRa-WiFi dual-mode communication. Content of the utility model

[0006] In order to overcome the defects of the prior art pointed out above, the present inventors have made in-depth research thereon, and after a lot of creative labor, the present utility model is completed.

[0007] Specifically, the technical problem to be solved by the present utility model is to provide an agricultural Internet of Things collection terminal based on LoRa-WiFi dual-mode communication, to solve the technical problems of current communication range limitation, transmission delay, single communication mode and low practicability.

[0008] To solve the above technical problems, the present utility model provides the following technical solutions:

[0009] An agricultural Internet of Things collection terminal based on LoRa-WiFi dual-mode communication, comprising a main control module, a LoRa module, a TYPE-C circuit, an LDO circuit, a CH340C chip, an automatic download circuit and an RS485 communication interface circuit;

[0010] The main control module has two CPU cores (which can be controlled separately) and runs at an adjustable clock frequency of 80 to 240MHz, and has multiple GPIO pins for communication and control with external devices;

[0011] The LoRa module is built-in with a power amplifier (PA) and a low noise amplifier (LNA), and the main control module is integrated with Wi-Fi and Bluetooth functions;

[0012] The VBUS, GND, CC1, CC2, D+, D-, SBU1 and SBU2 in the TYPE-C circuit are standard pin identifiers;

[0013] The LDO circuit is a forward low dropout regulator with an output voltage of 3.3V, wherein the VIN pin is the input voltage end, and the VOUT pin is the stable output voltage; the stable 5V input supplies power to the LoRa module, which is converted to 3.3V output by the voltage regulator, and supplies power to the main control module and the RS485 communication interface circuit.

[0014] As an improved technical solution, the CH340C chip connects a computer with an external hardware device through a USB interface, and the CH340C chip further comprises RTS, DTR, DCD, RI, DSR and CTS control signals for hardware flow control and line state indication.

[0015] As an improved technical solution, the automatic downloading circuit comprises two MOSFET metal-oxide semiconductor field effect transistors Q3 and Q4.

[0016] Further comprising resistors R16 and R17.

[0017] As an improved technical solution, the RS485 communication interface circuit has DE and RE control pins, and the RS485 communication interface circuit selects a MAX485ED chip to realize an RS-485 communication protocol.

[0018] After the above technical solution is adopted, the utility model has the beneficial effects that:

[0019] 1. The utility model discloses a kind of network deployment and operation costs can be reduced by integrating LoRa and WiFi, and independent network is not needed to be established and maintained for different application scenarios, so that network deployment is more flexible and convenient, and suitable communication technology can be selected according to actual demand and environmental conditions, and the low-power consumption characteristics of LoRa help reduce energy consumption, and the high-efficiency data transmission of WiFi reduces the idle time of equipment, and the combination of the two helps to realize more energy-saving network environment.

[0020] 2. The utility model discloses a kind of highly flexible and convenient for Internet of Things data transmission by LoRa and WiFi dual-mode communication technology, using high-speed WiFi communication in greenhouse environment, which is convenient and fast and convenient for networking;In field environment, distance is far, using LoRa communication ensures transmission distance, and removes the difficulty of network deployment and equipment maintenance.

[0021] 3. The utility model discloses a kind of data communication in low power can be realized by LoRa technology, suitable for agricultural tobacco field data acquisition.

[0022] 4. The utility model discloses a kind of spread spectrum modulation mode by LoRa technology, with strong anti-interference ability, suitable for communication in complex environment, WiFi signal shielding is serious, field area is too large and not suitable for deployment, and LoRa realizes long-distance anti-interference transmission.

[0023] 5. The utility model discloses a kind of LoRa and WiFi technology, which can be applied to a variety of Internet of Things application scenarios, and application scenarios are extensive. DRAWINGS

[0024] In order to more clearly illustrate the technical scheme of the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced as follows. Obviously, the drawings in the following description are only some embodiments of the present application, and for those skilled in the art, other drawings can be obtained without creative labor on the basis of these drawings. Among them:

[0025] Figure 1 The circuit structure schematic diagram of the present application based on the LoRa-WiFi dual-mode communication agricultural Internet of Things collection terminal based on the main control module ESP and the LoRa module.

[0026] Figure 2 The circuit diagram of the TYPE-C interface and the LDO low-dropout voltage stabilizer of the present application based on the LoRa-WiFi dual-mode communication agricultural Internet of Things collection terminal.

[0027] Figure 3 The circuit diagram of the key and the indicator light of the present application based on the LoRa-WiFi dual-mode communication agricultural Internet of Things collection terminal.

[0028] Figure 4 The electronic circuit diagram of the CH340 USB interface chip and the component connection of the present application based on the LoRa-WiFi dual-mode communication agricultural Internet of Things collection terminal.

[0029] Figure 5 The circuit diagram of the automatic download circuit of the present application based on the LoRa-WiFi dual-mode communication agricultural Internet of Things collection terminal.

[0030] Figure 6 The circuit diagram of the RS485 communication interface of the present application based on the LoRa-WiFi dual-mode communication agricultural Internet of Things collection terminal. DETAILED DESCRIPTION

[0031] The technical scheme in the embodiments of the present application will be described clearly and completely in combination with the drawings in the embodiments of the present application. Obviously, the described embodiments are only some embodiments of the present application, not all embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor are within the scope of protection of the present application.

[0032] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present application are only used to explain the relative positional relationship, movement condition, etc. between components in a certain posture (as shown in the drawings), and if the certain posture changes, the directional indications will also change accordingly.

[0033] Meanwhile, "and / or" or "and / or" appearing in the whole text means that it includes three schemes, for example, "A and / or B" includes A scheme, or B scheme, or A and B are satisfied at the same time.

[0034] In addition, the description of "first", "second" and the like in the present application is only for the purpose of description, and cannot be understood as indicating or implying the relative importance of the indicated technical features or implicitly indicating the number of the indicated technical features. Therefore, the features limited by "first", "second" can be explicitly or implicitly included at least one of the features. In addition, the technical solutions of each embodiment can be combined with each other, but it must be based on the realization of ordinary skilled in the art, when the combination of technical solutions appears contradictory or unachievable, it should be considered that the combination of technical solutions does not exist, also not within the protection scope required by the present application.

[0035] Referring to Figures 1-6 , a kind of agricultural IOT collection terminal based on LoRa-WiFi dual-mode communication is provided, this agricultural IOT collection terminal based on LoRa-WiFi dual-mode communication includes, main control module, LoRa module, TYPE-C circuit, LDO circuit, CH340C chip, automatic download circuit and RS485 communication interface circuit;

[0036] Referring to Figure 1 , main control module has two CPU kernels (can be controlled separately), with 80 to 240MHz adjustable clock frequency, and has multiple GPIO pins for communication, control with external device;

[0037] LoRa module is built-in power amplifier (PA) and low noise amplifier (LNA), and main control module model is ESP-WROOM-32, integrated with WiFi and Bluetooth function;Pin GPIO0 to GPIO26 acts as input / output, can be configured as digital input or output, analog input, etc.;EN, RXD, TXD and other ports are used as start signal, serial data reception and data transmission;

[0038] The circuit structure of main control module and LoRa module is as follows:

[0039] Main control module model is ESP-WROOM-32, integrated with WiFi and Bluetooth function;Pin GPIO0 to GPIO26 acts as input / output, can be configured as digital input or output, analog input, etc.;EN, RXD, TXD and other ports are used as start signal, serial data reception and data transmission.

[0040] LoRa module selects E22-400M33S, which carries out low-power long-distance wireless communication, and its SPI interface pin communicates with main control module data.

[0041] The 2-pin power supply of the main control module is connected to the ground, the 1-pin, 15-pin, 38-pin, 39-pin are connected to the ground, the 3-pin is connected to the automatic download circuit, the 4-pin, 5-pin are connected to the RS-485 serial port circuit, the 25-pin is connected to the key switch circuit, the 24-pin is connected to the LED indicator lamp circuit, the GPIO pin of the main control module is connected to the NSS, SCK, MOSI, MISO and BUSY pins of the LoRa module respectively, and communication is carried out through the SPI protocol, specifically, the 29-pin, 30-pin, 31-pin, 33-pin, 36-pin, 37-pin are connected to the 19-pin, 18-pin, 16-pin, 15-pin, 14-pin, 17-pin of the LoRa module. The 34-pin, 35-pin are connected to the CH340 circuit.

[0042] The 1-pin, 2-pin, 3-pin, 4-pin, 5-pin, 11-pin, 12-pin, 20-pin, 22-pin of the LoRa module are connected to the ground, the 9-pin, 10-pin are connected to the conversion 5V power supply, and the 13-19-pin are connected to the above-mentioned main control module;

[0043] Referring to Figure 2 , the VBUS, GND, CC1, CC2, D+, D-, SBU1, SBU2 in the TYPE-C circuit are standard pin identifiers.

[0044] The LDO circuit is a forward low dropout regulator with an output voltage of 3.3V, wherein the VIN pin inputs the voltage end and the VOUT pin stably outputs the voltage; the stable 5V input supplies power for the LoRa module, which is converted to 3.3V output by the voltage regulator, and supplies power for the main control module and the RS485 communication interface circuit;

[0045] The TYPE-C circuit is a 16PIN TypeC interface chip connected to the USB Type-C device, the VBUS is connected to the power supply, the CC1 and CC2 are configured as channels for detecting the direction and type of the cable, the D+, D- (A6, A7 pins, B6, B7 pins) transmit data signals, and the SBU1 and SBU2 can support additional communication protocols and additional functions. The A1 pin, A12 pin, B1 pin, B12 pin are connected to the ground.

[0046] The LDO circuit focuses on providing stable low voltage output through a linear voltage regulator, and the linear voltage regulator selects the AMS1117-3.3 model to adjust the input voltage of +5V to a fixed output voltage of 3.3V, ensuring the safety of the power supply of the main control module; the decoupling capacitors C7 and C9 filter out high-frequency noise and provide local energy storage to maintain the stability of the output voltage, the 1-pin is connected to the ground, the 3-pin is connected to the input 5V voltage, and the 2-pin, 4-pin are connected to the output 3.3V voltage.

[0047] Referring to Figure 4The CH340C chip connects a computer and an external hardware device through a USB interface, and the CH340C chip further includes RTS, DTR, DCD, RI, DSR and CTS control signals for hardware flow control and indication of a line state.

[0048] The CH340C chip converts the USB interface into a serial (RS232) interface to realize communication between a USB device and a serial port, and external element resistors R11 and R12 serve as pull-up or pull-down resistors to ensure that certain signal lines remain in a stable state when not driven; the USB differential data lines D+ and D- are connected to pins 5 and 6 to transmit USB data; U0_TXD and U0_RXD are connected to pins 2 and 3 to serve as UART (universal asynchronous receiver-transmitter) data transmission and reception lines, pin 1 is connected to ground, pins 4 and 16 are connected to a 3.3V voltage, and pins 13 and 14 are connected to an automatic download circuit through DTR and RTS.

[0049] With reference to Figure 5 The automatic download circuit includes two MOSFET metal-oxide-semiconductor field-effect transistors Q3 and Q4.

[0050] The automatic download circuit further includes resistors R16 and R17.

[0051] The automatic download circuit controls device start and stop and the like by detecting the DTR and RTS signal states; the D terminal of Q3 is connected to the DTR, and the D terminal of Q4 is connected to the RTS; based on the switching control signal transmission of the transistors Q3 and Q4, when the base receives a high-level signal from the DTR / RTS, the transistor is turned on, the current at the collector is increased, and finally the current is output through IO0.

[0052] With reference to Figure 6 The RS485 communication interface circuit has DE and RE control pins, and the RS485 communication interface circuit selects a MAX485ED chip to realize an RS-485 communication protocol.

[0053] The RS485 communication interface circuit amplifies data through a sending port TX end and a Q5 transistor, limits the current through a R18 resistor, and enters the RE and DE pins of a U11 MAX485ED chip; the RX end receives data and outputs the data from the RO pin of the U11 MAX485ED chip after limiting the current through a R21 resistor to reach an external device; U15, U12 and U13 are SMA connectors for high-frequency transmission of radio frequency signals, realize differential transmission of data, the DI pin and the GND pin are connected to ground, and the VCC pin is connected to a 3.3V voltage. Overall, the circuit can realize serial communication between two devices, the MAX485ED chip is responsible for processing the conversion of differential signals, and the peripheral resistors and capacitors help to stabilize and filter the signals.

[0054] It should be understood that the use of these embodiments is by way of illustration only and is not intended to limit the scope of the present application. In addition, it should also be understood that, after reading the technical content of the present application, those skilled in the art can make various modifications, modifications and / or variations to the present application, and all of these equivalent forms also fall within the protection scope defined by the claims attached to the present application.

Claims

1. An agricultural Internet of Things collection terminal based on LoRa-WiFi dual-mode communication, characterized in that: The main control module, LoRa module, TYPE-C circuit, LDO circuit, CH340C chip, automatic download circuit and RS485 communication interface circuit are included. The main control module has two CPU kernels, runs at a clock frequency of 80-240 MHz, and has multiple GPIO pins for communication and control with external devices. The LoRa module is built-in with a power amplifier (PA) and a low noise amplifier (LNA), and the main control module is integrated with Wi-Fi and Bluetooth functions. In the TYPE-C circuit, VBUS, GND, CC1, CC2, D+, D-, SBU1 and SBU2 are standard pin identifiers. The LDO circuit is a forward low dropout regulator with an output voltage of 3.3V, wherein the VIN pin is the input voltage end and the VOUT pin is the stable output voltage. 2.The LoRa-WiFi dual-mode communication based agricultural Internet of Things collection terminal according to claim 1, characterized in that: The stable 5V input is used to power the LoRa module, which is converted to 3.3V output by the regulator, and is used to power the main control module and the RS485 communication interface circuit. 3.The LoRa-WiFi dual-mode communication based agricultural Internet of Things collection terminal according to claim 1, characterized in that: The CH340C chip connects the computer and external hardware devices through the USB interface, and also includes RTS, DTR, DCD, RI, DSR and CTS control signals for hardware flow control and line status indication. The automatic download circuit includes two MOSFET metal-oxide-semiconductor field effect transistors Q3 and Q4. 4.The LoRa-WiFi dual-mode communication based agricultural Internet of Things collection terminal of claim 1, wherein: It also includes resistors R16 and R17. The RS485 communication interface circuit has DE and RE control pins, and the RS485 communication interface circuit selects MAX485ED chip to realize RS-485 communication protocol.

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