无源无线多参数微型传感器系统研发
发布时间：2019-06-13 18:42
【摘要】：射频识别RID)技术在过去的几十年渗透进了社会生活的方方面面,包括门禁管理,物流追踪,道路收费,国防安全等。然而在许多场合,需要能够检测震动、温度、压力、湿度等环境参数。例如,在密闭油漆喷涂房内,需要实时控制密闭空间内的温湿压状况,以使喷涂效果达到最佳；在旋转的轴承上,置入温度传感监测系统可以及时发现生产中存在的隐患。这些需求推动了微传感器技术与RFID技术的结合,形成了无线传感监控系统,也称为"RFID Sensor"。无线传感系统在可植入医疗器械、机械转动结构、密闭工业环境监测以及恶劣环境监测等方面具有得天独厚的优势,它在改变传统数据收集系统的同时也改变人类的生活生产方式。实现无线传感系统的途径既有有源遥测又有无源遥测。有源遥测系统提供了相对较长距离的双向数据传输能力,但尺寸比较大,而且受电池使用寿命的限制。无源遥测传输距离较短,但是由于内部无源,器件理论上可以拥有无限寿命。目前实现无源遥测有两种方式：一种是将电容式传感器与微电感串联形成LC传感器节点,通过检测LC谐振频率的变化完成环境参数的监控。另外一种是将微传感器与传感器检测电路集成,通过电路实现背反射调制将测量数据传递给外部。LC无源无线节点结构简单,但是需借助外部设备,且测量距离非常小。本论文设计出基于背反射调制的电感耦合式无源无线多传感器监测系统,非常适用于密闭空间的环境监测。主要的研究内容和创新包括：首先介绍了电感耦合系统的理论基础,比较几种无源无线传感器遥测系统优缺点。对基于射频反射调制的无源无线系统的研究现状作了分析,为后续设计打下理论基础。然后对基于射频反射调制的无源无线系统各个模块的设计做了理论分析,并利用软件进行电路仿真,寻找可行的系统电路实现方法。接着提出了适用于监测密闭空间和旋转结构的多个环境参数的系统,即基于背反射调制的电感耦合式多参数传感器环境监测系统。系统包括两部分：主系统和次系统。主次系统间通过互耦电感进行能量传输和数据接收。次系统集成了温湿压电容式传感器,采用松弛振荡器完成电容-频率的转换。利用时分复用电路实现多传感器的同步测量。将得到的频率信号调制主次系统电感上的载波,再由主系统的检波电路从已调载波中恢复频率信号。从频率信号中提取时钟信号,实现异步通信。利用主次电感共振的方式实现最大耦合距离。在完成设计后,将系统置于密闭的实验箱中进行温湿压测试。测试得到的温湿压曲线线性度和可重复性均良好。由于本系统中的C-f转换是非线性的,对于不同大小的电容式传感器转换精度不同。温湿压传感器的测量精度分别为0.52kHz/℃,-0.132kHz%RH和-0.156kHz/kPa。在本文的最后对后期工作进行展望,指出可以通过电感设计和阻抗匹配的方法提高系统的耦合效率,通过增加一个固定参考电容实现差频测量电容式传感器的方法,可以减少由于寄生参数和温度影响造成的测量误差,提高传感器测量精度。后期电路采用集成电路制造,可以大大降低系统的尺寸及功耗,使得系统的耦合距离大大增加,从而在医疗检测、工业控制、食品安全等领域有较为广阔的发展空间。
[Abstract]:Radio frequency identification (RID) technology has penetrated into all aspects of social life in the past decades, including access control, logistics tracking, road charging, national defense security, etc. However, in many applications, environmental parameters such as vibration, temperature, pressure, humidity, and the like can be detected. For example, in the closed paint spraying room, it is necessary to control the temperature and humidity pressure in the closed space in real time so as to achieve the best spraying effect; on the rotating bearing, the temperature sensing monitoring system can be put into the temperature sensing monitoring system to find the hidden danger existing in the production. These demands push the combination of the micro-sensor technology and the RFID technology to form a wireless sensor monitoring system, also known as a "RFID Sensor". The wireless sensing system has a unique advantage in the aspects of the implantable medical device, the mechanical rotating structure, the closed industrial environment monitoring and the severe environmental monitoring. The way to realize the wireless sensing system has both active and active telemetry. The active telemetry system provides a relatively long-distance bi-directional data transfer capability, but is large in size and is limited by battery life. The passive telemetry transmission distance is short, but due to internal passive, the device can theoretically have an infinite life. There are two ways to realize passive telemetry: one is to form an LC sensor node in series with the micro-inductor by the capacitive sensor, and the monitoring of the environmental parameters is completed by detecting the change of the LC resonance frequency. In addition, that micro-sensor is integrate with the sensor detection circuit, and the measurement data is transmitted to the outside through the back reflection modulation by the circuit. The LC passive wireless node is simple in structure, but requires the use of external devices and the measurement distance is very small. The paper designs an inductively coupled passive wireless multi-sensor monitoring system based on back reflection modulation, which is very suitable for environmental monitoring of confined space. The main research contents and innovations include: firstly, the theoretical basis of the inductive coupling system is introduced, and the advantages and disadvantages of several passive wireless sensor telemetry systems are compared. The research status of passive wireless system based on radio-frequency reflection modulation is analyzed, and a theoretical foundation is laid for the follow-up design. Then, the design of each module of the passive wireless system based on the radio-frequency reflection modulation is analyzed, and the circuit simulation is carried out by using the software, and a feasible system circuit implementation method is found. A system for monitoring a plurality of environmental parameters of a closed space and a rotating structure, that is, an inductively coupled multi-parameter sensor environment monitoring system based on back-reflection modulation, is then proposed. The system includes two parts: a master system and a secondary system. And energy transmission and data reception are carried out between the primary and secondary systems through the mutual coupling inductance. The secondary system integrates the temperature and humidity pressure capacitive sensor, and uses the relaxation oscillator to complete the conversion of the capacitance-frequency. A time division multiplexing circuit is utilized to realize the synchronous measurement of the multi-sensor. The obtained frequency signal is used to modulate the carrier on the primary and secondary system inductance, and the frequency signal is recovered from the modulated carrier by the detection circuit of the main system. The clock signal is extracted from the frequency signal and the asynchronous communication is realized. The maximum coupling distance is realized by means of primary and secondary inductive resonance. After completion of the design, the system was placed in a closed test box for temperature and wet pressure testing. The linearity and repeatability of the temperature and humidity curve obtained by the test are both good. Because the C-f conversion in the system is non-linear, the conversion accuracy of the capacitive sensors of different sizes is different. The measurement accuracy of the temperature and humidity sensor is 0.52 kHz/ 鈩，
本文编号：2498729
[Abstract]:Radio frequency identification (RID) technology has penetrated into all aspects of social life in the past decades, including access control, logistics tracking, road charging, national defense security, etc. However, in many applications, environmental parameters such as vibration, temperature, pressure, humidity, and the like can be detected. For example, in the closed paint spraying room, it is necessary to control the temperature and humidity pressure in the closed space in real time so as to achieve the best spraying effect; on the rotating bearing, the temperature sensing monitoring system can be put into the temperature sensing monitoring system to find the hidden danger existing in the production. These demands push the combination of the micro-sensor technology and the RFID technology to form a wireless sensor monitoring system, also known as a "RFID Sensor". The wireless sensing system has a unique advantage in the aspects of the implantable medical device, the mechanical rotating structure, the closed industrial environment monitoring and the severe environmental monitoring. The way to realize the wireless sensing system has both active and active telemetry. The active telemetry system provides a relatively long-distance bi-directional data transfer capability, but is large in size and is limited by battery life. The passive telemetry transmission distance is short, but due to internal passive, the device can theoretically have an infinite life. There are two ways to realize passive telemetry: one is to form an LC sensor node in series with the micro-inductor by the capacitive sensor, and the monitoring of the environmental parameters is completed by detecting the change of the LC resonance frequency. In addition, that micro-sensor is integrate with the sensor detection circuit, and the measurement data is transmitted to the outside through the back reflection modulation by the circuit. The LC passive wireless node is simple in structure, but requires the use of external devices and the measurement distance is very small. The paper designs an inductively coupled passive wireless multi-sensor monitoring system based on back reflection modulation, which is very suitable for environmental monitoring of confined space. The main research contents and innovations include: firstly, the theoretical basis of the inductive coupling system is introduced, and the advantages and disadvantages of several passive wireless sensor telemetry systems are compared. The research status of passive wireless system based on radio-frequency reflection modulation is analyzed, and a theoretical foundation is laid for the follow-up design. Then, the design of each module of the passive wireless system based on the radio-frequency reflection modulation is analyzed, and the circuit simulation is carried out by using the software, and a feasible system circuit implementation method is found. A system for monitoring a plurality of environmental parameters of a closed space and a rotating structure, that is, an inductively coupled multi-parameter sensor environment monitoring system based on back-reflection modulation, is then proposed. The system includes two parts: a master system and a secondary system. And energy transmission and data reception are carried out between the primary and secondary systems through the mutual coupling inductance. The secondary system integrates the temperature and humidity pressure capacitive sensor, and uses the relaxation oscillator to complete the conversion of the capacitance-frequency. A time division multiplexing circuit is utilized to realize the synchronous measurement of the multi-sensor. The obtained frequency signal is used to modulate the carrier on the primary and secondary system inductance, and the frequency signal is recovered from the modulated carrier by the detection circuit of the main system. The clock signal is extracted from the frequency signal and the asynchronous communication is realized. The maximum coupling distance is realized by means of primary and secondary inductive resonance. After completion of the design, the system was placed in a closed test box for temperature and wet pressure testing. The linearity and repeatability of the temperature and humidity curve obtained by the test are both good. Because the C-f conversion in the system is non-linear, the conversion accuracy of the capacitive sensors of different sizes is different. The measurement accuracy of the temperature and humidity sensor is 0.52 kHz/ 鈩，
本文编号：2498729
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