The purpose of this effort is to develop the first and largest SAW technology wireless multi-sensor array system for demonstration in NDE and SHM applications. SAW wireless sensors have proven performance in harsh and space environments due to their radiation harness, large temperature operation range, passive operation, and inherent solid state monolithic construction. SAW devices are manufactured in high volume and low cost, can be RFID encoded, operate at RF frequencies, and are small in size and weight. This Phase I project will provide the required elements for the Phase II implementation of a wireless passive sensor system.
The Phase I effort will provide an analysis and design study that includes the essential elements for a wireless SAW temperature sensor system, which include the test frame and sensor array, new RFID encoding theory for SAW device implementation, SAW device simulations and new embodiments, and system configuration analysis including post processing techniques. The approach will use several layers of SAW encoding including: PN phase shifting, orthogonal frequency coding, and time delay.
Temperature sensing will be the initial SAW device since it is ubiquitous and Pegasense has a large experience base. Various test-bed aeronautic materials will be studied for their electrical and mechanical properties, approaches considered for sensor mounting, and for RF communications.
The transceiver will use the latest developing systems within Pegasense, which is currently about a TRL 5, based on a software defined radio (SDR) approach using an ETTUS universal software radio peripheral (USRP). This effort an intended results will lay a foundation for understanding design principles and problem encountered in establishing large SAW based sensor arrays. The approach leverages NASA SBIR/STTR past efforts in software defined radio (SDR) that allows Pegasense to concentrate on the sensor array, materials and sensor advancements.
Because of the passive and rugged nature of SAW devices, there are a wealth of applications. A SAW device platform can be modified for differing operations by adding thin or thick films, or hybrid elements. Examples include: 1) ground operations- spacecraft lift off temperature and gas monitoring, cement NDE and gas sensing, 2) spacecraft - temperature, strain, radiation, and gas cabin monitoring, 3)space exploration- inflatable habitat, radiation and simple terrestrial positioning system, and 4) astronaut SHM - temperature and gas sensing.
Applications include: 1) radiation sensing in nuclear power plants, energy power grid monitoring, temperature monitoring in harsh environments, such as turbines, motors, engines, 2) hydrogen gas sensing for nuclear power plants, turbines and hydrogen storage containers, and 3) aviation industry wireless aircraft sensors for a wealth of applications needing multi sensor wireless passive sensors.