## 1 Introduction  
With the rapid development of modern computer technology and communication technology, the remote intelligent collection of domestic gas meter, water meter, electric energy meter and thermal energy meter information has become a major priority. The remote meter reading scheme has obvious technological advancement and economic advantages, while the traditional artificial way to check meters has many drawbacks and cannot meet the requirements of the new form. The remote meter reading system can transmit the data displayed on the user's gas meter to the server of the gas company in a timely manner [1]. Currently, the remote meter reading system is widely used in developed countries. Mechanical diaphragm gas meters are still widely used. Digitizing the gas measurement results of the existing gas meters has the following advantages. Firstly, using an intelligent meter reading method instead of the traditional manual meter reading method can greatly reduce the cost of labor. Secondly, the digital gas metering terminal can monitor the state of the user's gas usage in real time, thereby facilitating remote control. Thirdly, the intelligent gas meter can improve the safety of users' gas equipment and reduce the accident rate of gas leakage. In addition, the digital measurement results can be adjusted according to temperature and pressure to improve the accuracy of measurement results. At present, there are a large number of traditional mechanical diaphragm gas meters in the user market, which makes it difficult to install and popularize intelligent gas management equipment. Scholars in China and abroad have put forward some intelligent management schemes for diaphragm gas meters, among which the transformation of the meter body can be mainly classified as adding image processing equipment and changing the internal structure. [PERSON] studies a remote control gas meter reading system based on ZigBee wireless communication technology and digital image recognition technology [2]. In this scheme, the sensor node takes a picture of the gas meter using a CMOS camera, and sends it to the sink node through a multi-hop ZigBee network in the residential area. Similar to the above method, [PERSON] studies a remote gas meter reading system based on a wireless communication technology named LoRa [3]. This scheme mainly includes a machine vision system and a wireless communication system. The former refers to acquiring the image information of the dial of a diaphragm gas meter, and then obtaining the value by using image processing. The latter involves using the LoRa module to send the gas consumption data to the server. Although these methods have high credibility and do not require changing the existing gas meter and gas pipelines, they demand high levels of the image transmission and processing algorithm's efficiency and the computer hardware used to process pictures. [PERSON] utilizes the M-Bus networks and GPRS wireless transmission technology to achieve remote control and transmission of data using the gas meter [4]. In the paper, the author mounts the nonmetallic-metal valves rotating wheel on the character wheel. The MSP430 FW427 generates the excitation signal to the LC circuit to produce damped oscillation. When the inductor is in the nonmetallic film, the damping attenuation becomes smaller, while when the inductor is not in the nonmetallic film, it becomes larger. Finally, the rotation of the character wheel is recognized by detecting the status of the inductor. The biggest drawback of this retrofit method is that the diaphragm gas meter needs to be disassembled and reconstructed. [PERSON] studies the intelligent meter reading scheme based on AC-250 film gas meter produced by the American Meter Company [5]. The scheme involves installing the Omega FMA3340 high-precision airflow meter and pressure detecting device at the gas outlet of the diaphragm gas meter, and then adding an optical encoder to the gas meter gear to obtain the rotation parameters.