Smart Sensors Based on Integrated Optics and Microelectromechanical Systems

摘要

The integration of real-time digital signal processing with sensor technology has spurred a renewed effort for 'smart sensors' in military applications. For example, there has been a resurgence in the U.S. Army's interest in low-frequency acoustic sensors for the identification and tracking of targets such as tracked vehicles, airborne vehicles, and munition muzzle blasts. For this particular application, there exists a need for compact, rugged, and very sensitive arrays of acoustic sensors. The broad objective of this research effort is development of the technology leading to a novel sensor based on optical interferometry, microelectromechanical systems (MEMS), and digital signal processing (DSP). The synergistic integration of these three technologies provides the advantages of high sensitivity, frequency selectivity, and the possibility of sensor array integration in a compact and robust package. These features are required for use on the digital battlefield. To achieve the desired smart sensor based on MEMS and optical sensing, the authors have identified two specific technological areas of need: (1) development of a robust interferometric system to measure the out-of-plane deflection of a MEMS structure, and (2) development of DSP algorithms for demodulation of the interferometer. The progress made in each of these two technological areas of need is reported here. A list of publications supported under this contract is included. (2 tables, 22 figures, 35 refs.).