阅读说明：本技术 热电偶或热电阻无线传输系统 (Thermocouple or thermal resistor wireless transmission system ) 是由 赵仕海 丁世杰 李刚 胡翠 常宽 于 2021-08-06 设计创作，主要内容包括：热电偶或热电阻无线传输系统,包括前端采集单元和后端接收单元,所述前端采集单元包括依次设置的传感器、模数转换变送器、第一微控制器、第一LORA收发兼容模块、第一LORA天线,所述后端接收单元包括第二LORA天线、第二LORA收发兼容模块、第二微控制器、数模转换变送器；后端接收单元可对应获得多个前端采集单元的信号,这样可以实现一个接收单元可以同时获得多个传感器的信号；所述第一微控制器和第二微控制器还包括校验程序。发明实现了热电偶或热电阻信号的无线传输,取代传统电缆传输模式,并且第一微控制器和第二为控制的校验程序保证了数据的一一对应传输和数据的正确性。(The thermocouple or thermal resistor wireless transmission system comprises a front-end acquisition unit and a rear-end receiving unit, wherein the front-end acquisition unit comprises a sensor, an analog-to-digital conversion transmitter, a first microcontroller, a first LORA transceiving compatible module and a first LORA antenna which are sequentially arranged, and the rear-end receiving unit comprises a second LORA antenna, a second LORA transceiving compatible module, a second microcontroller and a digital-to-analog conversion transmitter; the rear-end receiving unit can correspondingly obtain signals of a plurality of front-end acquisition units, so that one receiving unit can simultaneously obtain signals of a plurality of sensors; the first microcontroller and the second microcontroller further comprise a verification program. The invention realizes wireless transmission of thermocouple or thermal resistance signals, replaces the traditional cable transmission mode, and ensures one-to-one corresponding transmission of data and correctness of the data by the first microcontroller and the second controlled verification program.)

1. The thermocouple or thermal resistor wireless transmission system is characterized by comprising a front-end acquisition unit and a rear-end receiving unit, wherein the front-end acquisition unit comprises a sensor, an analog-to-digital conversion transmitter, a first microcontroller, a first LORA transceiving compatible module and a first LORA antenna which are sequentially arranged, and the rear-end receiving unit comprises a second LORA antenna, a second LORA transceiving compatible module, a second microcontroller and a digital-to-analog conversion transmitter; the rear-end receiving unit can correspondingly obtain signals of a plurality of front-end acquisition units, so that one receiving unit can simultaneously obtain signals of a plurality of sensors;

the first microcontroller and the second microcontroller further comprise a verification program, and the verification program is as follows:

s1, adding a check bit into the digital signal converted by the sensor by the first microcontroller;

s2, the front end acquisition unit and the rear end acquisition unit transmit data within a set frequency range;

s3, judging whether the transmission frequency ranges of the front-end acquisition unit and the rear-end acquisition unit are crossed, if so, determining another wireless transmission frequency range without the crossing of the transmission frequency range of the front-end acquisition unit according to the relative position of the transmission frequency range of the front-end acquisition unit in a preset frequency area and the interval length occupied by the rear-end acquisition unit in the preset frequency area, and then entering the step S4; if not, go to step S2;

s4, after the second microcontroller confirms the received signal, screening the data, confirming whether the check bit data is correct, and if not, entering the step S5 by sending a signal to the first microcontroller; otherwise, the data is converted and transmitted to be processed in a second LPRA transceiving compatible module;

s5, the first microcontroller initializes the data to obtain new data, changes the checking mode and checks again, and then the step S2 is entered, and the second microcontroller correspondingly changes the checking contrast according to the times sent to the first microcontroller.

2. The thermocouple or thermistor wireless transmission system according to claim 1, characterized in that it further comprises a relay unit comprising a third LORA antenna, a LORA gateway, a fourth LORA antenna arranged in sequence.

3. The thermocouple or thermistor wireless transmission system according to claim 1, characterized in that the sensor is a 4-channel PT100 temperature acquisition sensor, and the LORA transceiver-compatible module is based on SEMTECH inlet chip SX 1278.

4. The thermocouple or thermistor wireless transmission system according to claim 1, characterized in that the first LORA transceiver-compatible module comprises a UART universal asynchronous receiver transmitter and a spread spectrum transmission module connected in series.

5. The thermocouple or thermistor wireless transmission system according to claim 1, characterized in that the front-end acquisition unit and the rear-end reception unit are packaged as an independent module, and the corresponding first LORA antenna and second LORA antenna are configured as internal transmission antennas or external transmission antennas according to different schemes.

6. The thermocouple or thermal resistor wireless transmission system according to any one of claims 1-3, wherein the second microcontroller comprises two operation modes, one operation mode is that Modbus industrial protocol is directly written into data bus interface such as RS485/RS232 of industrial control system such as PLC/DCS/DDS; the second working mode is that the analog quantity acquisition interface of the sensor which is switched back to the original signal of the sensor through the millivolt voltage/millivolt current conversion circuit and is accessed to the industrial control systems such as PLC/DCS/DDS is obtained from the second microcontroller clock.

Technical Field

The invention relates to the technical field of sensors, in particular to a wireless transmission system of a thermocouple or a thermal resistor.

Background

Sensors play a very important role in the industrial 4.0 era. With the application and popularization of the internet of things in the industrial field, the application of the sensor in the internet of things is more and more extensive. The sensors are the bottommost layer and the frontmost edge of the technology of the Internet of things, and have very important significance for the development of the industry of the Internet of things. In recent years, the support of the policy of the internet of things in China is continuously increased, and China has remarkable effects on the aspects of key technology research and development of the internet of things, application demonstration and popularization, industrial coordinated development, policy environment construction and the like, and becomes one of the most active areas in the development of the internet of things in the world.

The data show that the annual composite growth rate of the Internet of things market in a certain period of time reaches 25%, and the overall scale of the Internet of things in China is estimated to reach 2.2 trillion yuan by 2020, as shown in FIG. 1. Against this background, the market for sensors has also grown further. According to data, the market scale of the sensor in China in 2017 is 1815 million yuan, the sensor breaks through 2000 million yuan in 2018, the application range of the sensor is expanded in 2019, the market scale is further expanded, and the market scale is estimated to be about 2310 million yuan.

The traditional sensor data transmission structure is that a sensing element, a conversion element and a conversion circuit are used for finally obtaining signals corresponding to temperature, air pressure and noise, and in the process, the conversion element and the conversion circuit are supported by an auxiliary power supply.

However, since it is not easy to obtain data in some remote areas, accurate transmission of data detected by the sensors is a critical issue.

Disclosure of Invention

In order to realize accurate transmission of data detected by a sensor, the invention provides a wireless transmission system of a thermocouple or a thermal resistor, and the specific scheme is as follows:

the thermocouple or thermal resistor wireless transmission system comprises a front-end acquisition unit and a rear-end receiving unit, wherein the front-end acquisition unit comprises a sensor, an analog-to-digital conversion transmitter, a first microcontroller, a first LORA transceiving compatible module and a first LORA antenna which are sequentially arranged, and the rear-end receiving unit comprises a second LORA antenna, a second LORA transceiving compatible module, a second microcontroller and a digital-to-analog conversion transmitter; the rear-end receiving unit can correspondingly obtain signals of a plurality of front-end acquisition units, so that one receiving unit can simultaneously obtain signals of a plurality of sensors;

the first microcontroller and the second microcontroller further comprise a verification program, and the verification program is as follows:

s1, adding a check bit into the digital signal converted by the sensor by the first microcontroller;

s2, the front end acquisition unit and the rear end acquisition unit transmit data within a set frequency range;

s3, judging whether the transmission frequency ranges of the front-end acquisition unit and the rear-end acquisition unit are crossed, if so, determining another wireless transmission frequency range without the crossing of the transmission frequency range of the front-end acquisition unit according to the relative position of the transmission frequency range of the front-end acquisition unit in a preset frequency area and the interval length occupied by the rear-end acquisition unit in the preset frequency area, and then entering the step S4; if not, go to step S2;

s4, after the second microcontroller confirms the received signal, screening the data, confirming whether the check bit data is correct, and if not, entering the step S5 by sending a signal to the first microcontroller; otherwise, the data is converted and transmitted to be processed in a second LPRA transceiving compatible module;

s5, the first microcontroller initializes the data to obtain new data, changes the checking mode and checks again, and then the step S2 is entered, and the second microcontroller correspondingly changes the checking contrast according to the times sent to the first microcontroller.

Specifically, the system further comprises a relay unit, wherein the relay unit comprises a third LORA antenna, a LORA gateway and a fourth LORA antenna which are sequentially arranged.

Specifically, the sensor is a 4-channel PT100 temperature acquisition sensor, and the LORA transceiving compatible module adopts an inlet chip SX1278 based on SEMTECH company.

Specifically, the first LORA transceiver-compatible module includes a UART universal asynchronous receiver transmitter and a spread spectrum transmission module, which are connected in sequence.

Specifically, the front-end acquisition unit and the rear-end reception unit are packaged as an independent module, and the corresponding first LORA antenna and the corresponding second LORA antenna are configured as an internal transmission antenna or an external transmission antenna according to different schemes.

Specifically, the second microcontroller comprises two working modes, wherein one working mode is that a Modbus industrial protocol is directly written into data bus interfaces such as RS485/RS232 of industrial control systems such as PLC/DCS/DDS in a digital mode; the second working mode is that the analog quantity acquisition interface of the sensor which is switched back to the original signal of the sensor through the millivolt voltage/millivolt current conversion circuit and is accessed to the industrial control systems such as PLC/DCS/DDS is obtained from the second microcontroller clock.

The invention has the beneficial effects that:

(1) the invention realizes wireless transmission of thermocouple or thermal resistance signals, replaces the traditional cable transmission mode, and ensures one-to-one corresponding transmission of data and correctness of the data by the first microcontroller and the second controlled verification program.

(2) The invention realizes the acquisition, processing and wireless digital transmission of thermocouple/resistance signals; and the wireless receiving, processing and analog signal conversion output of the thermocouple/resistance signal are realized.

(3) The invention realizes the modular design of the signal sending end and the signal receiving end and carries out independent packaging.

Drawings

Fig. 1 is a structural diagram of a front-end acquisition unit.

Fig. 2 is a structural diagram of a relay unit.

Fig. 3 is a structural diagram of the rear-end receiving unit.

11. A sensor; 12. an analog-to-digital conversion transmitter; 13. a first microcontroller; 14. a first LORA transceiving compatible module; 141. a UART universal asynchronous receiver transmitter; 142. a spread spectrum transmission module; 15. a first LORA antenna; 21. a third LORA antenna; 22. a LORA gateway; 23. a fourth LORA antenna; 31. a second LORA antenna; 32. a second LORA transceiver-compatible module; 33. a second microcontroller; 34. and a digital-to-analog conversion transmitter.

Detailed Description

As shown in fig. 1-3, thermocouple or thermal resistance wireless transmission system, including front end acquisition unit and rear end receiving unit, the front end acquisition unit is including the sensor, analog-to-digital conversion changer, first microcontroller, the compatible module of first LORA transceiver, the first LORA antenna that set gradually, rear end receiving unit includes the compatible module of second LORA antenna, second LORA transceiver, second microcontroller, digital-to-analog conversion changer. The rear receiving unit can correspondingly obtain signals of a plurality of front collecting units, so that one receiving unit can simultaneously obtain signals of a plurality of sensors.

Preferably, as shown in fig. 2, the wireless communication device further includes a relay unit, which includes a third LORA antenna, a LORA gateway, and a fourth LORA antenna sequentially disposed.

In this embodiment, the sensor is a 4-channel PT100 temperature acquisition sensor, and the LORA transceiver-compatible module is based on an inlet chip SX1278 (transceiver integrated) by SEMTECH corporation.

Specifically, the first LORA transceiver-compatible module includes a UART universal asynchronous receiver transmitter and a spread spectrum transmission module, which are connected in sequence.

The front-end acquisition unit and the rear-end receiving unit are packaged into an independent module, and the corresponding first LORA antenna and the corresponding second LORA antenna are configured into an internal transmission antenna or an external transmission antenna according to different schemes. The first microcontroller and the second microcontroller both use SOC chips.

The second microcontroller comprises two working modes, wherein one working mode is that Modbus industrial protocols are directly and digitally written into data bus interfaces such as RS485/RS232 of industrial control systems such as PLC/DCS/DDS and the like. The second working mode is that the analog quantity acquisition interface of the sensor which is switched back to the original signal of the sensor through the millivolt voltage/millivolt current conversion circuit and is accessed to the industrial control systems such as PLC/DCS/DDS is obtained from the second microcontroller clock.

The temperature sensor is a temperature sensor, the temperature sensor converts the temperature to be acquired into analog voltage/current signals such as current or voltage through a thermocouple/thermal resistor, the analog voltage/current signals are converted through an SOC chip and transmitted in a wireless mode, and then the analog voltage/current signals are simulated back to original signals through a receiving end, so that the wireless access of the temperature sensor can be realized under the condition that an original control system is not changed.

The thermocouple sensor generates output voltage of the millivolt sensor, resistance of the thermal resistance sensor changes along with temperature changes, the sensor converts analog signals into digital signals through the embedded analog-to-digital conversion transmitter, the digital signals are controlled and read by an SOC chip in the first microcontroller through an IIC bus protocol or an SPI bus protocol, the digital signals and the temperature of a detection point keep a fixed transfer function relationship, and the SOC chip reversely estimates the temperature of the detection point through the transfer function relationship. After the data collected by the first microcontroller are converted, the data are transmitted to the spread spectrum transmission module through the UART universal asynchronous receiver-transmitter in the first LORA receiving-transmitting compatible module, and the spread spectrum transmission module modulates the received information to the radio wave of the corresponding frequency band and transmits the radio wave out through the first LORA antenna.

The second LORA antenna in the other rear-end receiving unit within the transmission distance receives radio wave signals from the air, effective information is analyzed by the second LORA receiving and transmitting compatible module, the information is transmitted to the SOC chip in the second microcontroller through the UART bus, the SOC chip in the second microcontroller can further analyze and convert the information after receiving the information, the voltage signal of 0-3.3V is output through the digital-analog conversion transmitter, and the signal which is the same as that of the sensor can be output to the existing automatic control system after the conversion of the thermocouple or the thermal resistance analog circuit, so that the non-inductive switching is realized without modifying the program of the existing control system. The wireless transmission can also adopt a 4G communication network.

The first microcontroller and the second microcontroller further comprise a verification program, and the verification program is as follows:

s1, adding a check bit into the digital signal converted by the sensor by the first microcontroller;

s2, the front-end acquisition unit, the relay unit and the rear-end acquisition unit transmit data within a set frequency range;

s3, judging whether the transmission frequency ranges of the front-end acquisition unit and the rear-end acquisition unit are crossed, if so, determining another wireless transmission frequency range without the crossing of the transmission frequency range of the front-end acquisition unit according to the relative position of the transmission frequency range of the front-end acquisition unit in a preset frequency area and the interval length occupied by the rear-end acquisition unit in the preset frequency area, and then entering the step S4; if not, go to step S2;

s4, after the second microcontroller confirms the received signal, screening the data, confirming whether the check bit data is correct, and if not, entering the step S5 by sending a signal to the first microcontroller; otherwise, the data is converted and transmitted to be processed in a second LPRA transceiving compatible module;

s5, the first microcontroller initializes the data to obtain new data, changes the checking mode and checks again, and then the step S2 is entered, and the second microcontroller correspondingly changes the checking contrast according to the times sent to the first microcontroller.

The above description is only for the preferred embodiment of the present invention, but the scope of the present invention is not limited thereto, and any person skilled in the art should be considered to be within the technical scope of the present invention, and the technical solutions and the inventive concepts thereof according to the present invention should be equivalent or changed within the scope of the present invention.