A Wireless Passive SAW Delay Line Temperature and Pressure Sensor for Monitoring Water Distribution System

Wireless passive surface acoustic wave (SAW) sensor has been widely used in many applications. This paper presents a feasibility study on a designed wireless passive SAW delay line temperature and pressure sensor for monitoring water distribution systems. The substrate of the sensor node is a Y-Z orientation cut LiNbO3 crystalline with 0.5 mm thickness. The Interdigital transducer (IDT) was fabricated centrally on the surface of the substrate with an antenna connected. There are three reflectors fabricated on the same surface of the IDT. One reflector is on one side and the other two are on the other side of the IDT. A simulated water pipe platform with testing devices was assembled to test the feasibility of the sensor node working in water pipe environment. The experimental result showed that the designed sensor worked properly but 4/5 amplitude of signals is lost compared to the experimental results in the open-air environment

SAW Delay Line based Smart Sensing in Water Distribution System

Wireless Passive Surface Acoustic Wave (SAW) sensors have attracted great attention in numerous applications. They are powered by interrogating Radio Frequency (RF) pulses rather than batteries. In this study, a wireless passive SAW temperature and pressure delay line sensor was adapted in a designed framework which can control the ambient liquid temperature and pressure and characterised. The experimental results meet the theoretical analysis that the related phase delay of the response signal depends linearly on the temperature (pressure) when the pressure (temperature) keeps constant

Feasibility Study on Wireless Passive SAW Sensor in IoT enabled Water Distribution System,

Internet of Things (IoT) technology has recently been widely utilized into a variety of industrial applications. Wireless Passive Surface Acoustic Wave (SAW) sensors have attracted great attention in numerous IoT enabled applications. The sensor nodes are not directly supplied by the power supply as it absorbs the energy from the interrogating Radio Frequency (RF) pulses to excite the SAW. Temperature and pressure are two imperative parameters to monitor whether the pipelines in water distribution system are properly functioning. In this study, the wired and wireless response signals of the passive SAW delay line temperature and pressure sensor is compared. There is a 1/5 attenuation on the response signal when wireless interrogation and response signal receiving process is applied. A wireless passive SAW delay line temperature and pressure sensor was planted in a framework simulating the environment of the water pipelines, and the response signals of the sensor node in different ambient environments are analysed and compared. Compared to the air environment, there is only a sight attenuation of the response signal when the sensor node is planted in the simulating water pipeline environment framework