【作者】 张弛；

【导师】 骆季奎；

【作者基本信息】 浙江大学 ， 电子科学与技术， 2024， 博士

【摘要】 近年来,物联网(Internet of Things,IoT)和包含大量传感器的无线传感网络(Wireless Sensor Networks,WSN)发展迅速,吸引了众多研究人员和工业界的关注。它们被广泛应用于智慧城市、智能制造和医疗保健等各个领域。物联网和无线传感网络的基础和核心技术是数以亿万计的微纳传感器,这些传感器用于感知、收集周围环境的信息。物联网和无线传感器网络面临的一个关键问题是如何长期稳定、有效地为大量微型传感器供电。虽然电池供电仍然是主要方法,但是电池寿命短,需要定期更换。特别是当传感器分布在封闭的区域(如植入人体的传感设备)或偏远、恶劣的环境中时,电池的更换和维护变得十分麻烦,消耗大量的人力物力。无线无源传感器和自供电无线传感器能够有效解决上述问题。因此,提升这两类无线传感器的性能以及开发新的应用,对促进物联网和无线传感网络的发展具有重要意义。对于无线无源传感器,本文主要涉及LC(Inductor capacitor)无线无源传感器和平面微波谐振器无线无源传感器。LC无线无源传感器的最新研究进展是一种基于宇称对称概念的高精度LC无线无源传感器。但是,这类传感器使用传统的扫频测量方法。测量精度和速度受限于频域分析仪器的性能和速度。本文提出一种瞬态响应测量方法,极大的提高了系统的测量速度。开口谐振环(SRR)是平面微波谐振器无线无源传感器最常用的谐振器之一,研究者发现声表面波(SAW)器件的金属叉指电极与SRR具有相似的特性,可以用作平面微波谐振器。基于这个原理,本文提出了一种基于SAW器件结构的可以同时检测和去除雾和冰的多功能平台。对于自供电无线传感器,本文主要涉及一种新型的基于摩擦纳米发电机(Triboelectric nanogenerator,TENG)的瞬时自供电无线传感系统。为了解决这类传感系统存在的信号不稳定、传感距离近、传感精度低以及单参数传感的缺点,本文创新性地提出了基于TENG的全自动自供电无线传感器、多参数自供电无线传感器、高精度自供电无线传感器和远距离自供电无线传感器。本文的主要研究内容和成果总结如下:(1)提出了一种用于宇称对称性LC无线无源传感系统的瞬态响应测量方法,利用专门设计的电路控制读取器周期性地产生瞬态响应信号,而无需使用频域分析仪器。通过检测响应信号的包络和振幅的变化或信号的快速傅里叶变换频谱(FFT)峰值位置的变化来实现无线传感功能。当网络分析仪扫频范围为5MHz,测量频率精度为1k Hz时,新方法的测量速度比传统的频域分析方法快大约1000倍。(2)提出了一种基于SAW器件结构的可以同时检测和去除雾和冰的多功能平台。当叉指电极作为微波谐振器使用时,该平台可用于实时监测器件表面的水和冰的存在状态;当SAW器件被用来产生声表面波时,所产生的声表面波可以用于除雾和除冰。(3)开发了一种基于场效应管(MOSFET)的电子开关,它极大的提高了传统TENG瞬时自供电无线传感系统发射信号的稳定性(振幅和频率)。通过使用多个相互耦合的LC谐振器产生发射信号,实现了瞬时多参数传感功能。并将该系统应用于自供电无线胎压监测系统,实现了实时监测自行车的胎压和速度,分辨率为5.5 k Pa,精度约为97%。(4)通过引入负阻LC谐振器作为发射器,将发射信号的持续时间从传统的10-20μs大大的提升到了1 ms,将传统TENG瞬时自供电无线传感系统的传感精度提升了40倍。本文还提出了一种基于单晶体管振荡器的TENG瞬时自供电无线传感系统,该系统可直接将TENG的输出电压转换为433 MHz的传感信号,然后通过天线进行发射和接收,实现了50 m的无线传感距离。更多还原

【Abstract】 Nowadays,the Internet of things(IoT)and Wireless Sensor Networks(WSNs)containing a large number of sensors have attracted vast attention from researchers and industries.They have been widely used in various fields,such as smart home,intelligent manufacturing,and healthcare etc.The foundation and core technology for both the IoT and WSNs are the millions of microsensors that are used to collect a vast amount information.One critical issue for IoTs and WSNs is how to power the large number of microsensors efficiently.Although battery-based power sources are still the choice for the applications,they have limitations such as short battery life and the need for periodic replacement.This issue becomes particularly troublesome when sensors are deployed in enclosed areas(such as implanted medical devices)or in remote and harsh environments,where battery replacement and maintenance are highly impractical.Self-powered wireless sensors and wireless passive sensors offer effective solutions to these problems.Therefore,enhancing the performance of these types of sensors and developing new applications for these sensors are crucial for advancing the development of IoT and WSNs.For wireless passive sensors,this paper mainly covers inductor capacitor(LC)wireless passive sensors and microwave resonator-based wireless passive sensors.The latest advancement in LC wireless passive sensors is a high-precision LC wireless passive sensor based on the concept of parity-time symmetry.However,these sensors traditionally use frequency sweep measurement methods,where the measurement accuracy and speed largely depend on the performance of the frequency domain analysis instruments.We propose a transient response measurement method that significantly improves the system’s measurement speed.The split ring resonator(SRR)is one of the most commonly used planar microwave resonators in planar microwave resonator-based wireless passive sensors.We found that the electrode metal layer of surface acoustic wave(SAW)devices exhibits similar characteristics to the SRR and can be used as a planar microwave resonator.We proposed a multifunctional platform based on the structure of the SAW device,utilizing this principle.For self-powered wireless sensors,this paper primarily discusses a novel instantaneous self-powered wireless sensing system based on triboelectric nanogenerator(TENG).To address the issues of signal instability,short sensing distance,low sensing accuracy,and the limitation of sensing only a single parameter in such systems,we innovatively propose a fully automatic TENG instantaneous self-powered wireless sensors,a multi-parameter TENG instantaneous self-powered wireless sensors,a high-precision TENG instantaneous self-powered wireless sensors,and a long-distance TENG instantaneous self-powered wireless sensors.The main research content and achievements of this paper are summarized as follows:(1)A transient response measurement method for Parity-Time symmetry LC wireless passive sensing systems was proposed.This method uses a specially designed circuit to control the reader to periodically generate transient response signals,eliminating the need for frequency domain analysis instruments.The sensing functionality is achieved by detecting changes in the envelope and amplitude of the response signal or changes in the fast Fourier transform(FFT)peaks of the signal.The measurement speed of the new method is approximately 1000 times faster than that of traditional frequency domain analysis methods,given that the frequency sweep range of the network analyzer is 5 MHz and the measurement frequency accuracy is 1 k Hz.(2)We proposed a multifunctional platform based on the structure of SAW devices that can simultaneously detect and remove fog and ice.When the interdigital electrode metal layer is used together with piezoelectric material as a traditional SAW device,it generates surface acoustic waves for defogging and deicing.When the interdigital electrode metal layer is used as a microwave resonator,the platform can monitor the presence and quantity of water and ice on the device’s surface in real-time.(3)We developed an electronic switch based on a Metal-Oxide-Semiconductor Field-Effect Transistor(MOSFET),which significantly improves the stability(amplitude and frequency)of the transmiting signal in traditional TENG instantaneous self-powered wireless sensing systems.By using multiple mutually coupled LC resonators to generate the transmiting signal,the sensing system has multi-parameter sensing functionality.A self-powered wireless tire pressure monitoring system was proposed which is capable of real-time monitoring bicycle tire pressure and speed,with a resolution of 5.5 k Pa and an accuracy of approximately 97%.(4)By introducing a negative resistance-based LC resonator as a transmitter,the duration of the transmiting signal was increased from the traditional 10-20μs to 1 ms.This enhancement improves the sensing accuracy of the traditional TENG instantaneous self-powered wireless sensing system by 40 times.We also proposed a TENG instantaneous self-powered wireless sensing system based on a single transistor oscillator.This system can directly convert the output voltage of TENG into a 433 MHz sensing signal,which is then transmitted and received via an antenna.The new system’s sensing distance is up to 50 meters.更多还原