A sensing system includes: a surface acoustic wave sensor with a first surface acoustic wave device-and a second surface acoustic wave device; a sensing apparatus detecting an electrical characteristic of the first and second surface acoustic wave devices connected to the surface acoustic wave sensor; and a control apparatus calculating a physical quantity acting on one of a target to which the surface acoustic wave sensor is attached and the surface acoustic wave sensor. The sensitivity ratio of a first physical quantity and the sensitivity of a second physical quantity are different, and a third physical quantity is removable by averaging. The control apparatus removes the first physical quantity based on the results of a comparison operation on sensor signals from the first and second surface acoustic wave elements, uses the averaging process to remove the third physical quantity, and thereby calculates the second physical quantity.

A patch-type passive acoustic waving sensing device includes a surface acoustic wave sensor and at least a first and second rubber sheets. A cross-section of each of the first and second rubber sheets is larger than that of the surface acoustic wave sensor. A bottom of the surface acoustic wave sensor is on an upper surface of the first rubber sheet, and a first central hole allowing the surface acoustic wave sensor to penetrate therethrough is formed in a center of the second rubber sheet. The surface acoustic wave sensor penetrates the first central hole, and the second rubber sheet is fixedly connected to the upper surface of the first rubber sheet. The surface acoustic wave sensor includes pins at the bottom thereof such that free ends of the pins are connected to an antenna, and the antenna and some of the pins are inside the first rubber sheet.

A detection system and a wind driven generator. The detection system includes: a plurality of passive wireless sensors respectively provided at the corresponding positions to be detected, which are used for obtaining detection signals of the positions to be detected; and a leaky coaxial cable provided along the position to be detected, wherein the leaky coaxial cable can emit electromagnetic waves to drive the plurality of passive wireless sensors, and can receive the detection signal sent by the passive wireless sensors. The detection system can save installation space, as well as reduce maintenance costs since there is no need to replace a battery regularly, and when conducting multi-point measurements, costs are reduced and the number of passive wireless sensors that the system can configure is increased.

The invention concerns a system for monitoring physical and/or analogue parameters relative to the parts of an engine, said system comprising at least one electronic control unit (30.sub.a) configured to call up data, via at least one antenna (20a), from a surface acoustic wave sensor located on one of said parts, characterised by the fact that:—the engine (M) is compartmentalized, each compartment (Ma, . . . , Mf) comprising a plurality of mobile or fixed parts of which the physical and/or analogue parameters need to be monitored, —each of these parts to be monitored is provided with a surface acoustic wave sensor (101a, 102a, 103a, . . . , 101f, 102f, 103f), each of said sensors having a distinct resonance frequency specific to it,—an antenna (20a, . . . , 20f) is installed inside each of the compartments (Ma, . . . , Mf), each of said antenna being connected, alone or in pairs, to an electronic control unit (30a, . . . , 30f, 30ab, . . . , 30ef),—each antenna (20a, . . . , 20f) is controlled by the electronic control unit (30a, . . . , 30f, 30ab, . . . , 30ef) to which it is connected, to simultaneously emit a plurality of distinct frequencies close to the resonance frequencies of the sensors (101a, 102a, 103a, . . . , 101f, 102f, 103f) which are located in the engine compartment (Ma, . . . , Mf) of said antenna, so as to simultaneously communicate with all of these sensors (101a, 102a, 103a, . . . , 101f, 102f, 103f).

A passive and wireless sensor is provided for sensing at least one of magnetic field, temperature or humidity. The sensor can provide only one of the sensing functions, individually or any combination of them simultaneously. It can be used for various applications where magnetic field changes, temperature and/or humidity need to be measured. In one or more embodiments, a surface acoustic wave (SAW) sensor is provided that can measure one or more of a magnetic field (or current that generates the magnetic field), temperature and humidity. In one or more embodiments, a magnetoimpedence (MI) sensor (for example a thin film giant magnetoimpedance (GMI) sensor), a thermally sensitive (for example a Lithium Niobite (LiNbO.sub.3)) substrate, and a humidity sensitive film (for example a hydrogel film) can be used as sensing elements.

In some embodiments, a sensor package includes: a substrate including a sensing area; a terminal portion disposed on a side of the sensing area of the substrate and including at least one terminal connected to the outside; a first outer wall disposed on the substrate and including a main wall surrounding at least some outer portions of the sensing area; at least one wire patterned and disposed on the substrate and configured to connect the sensing area and the terminal portion to each other; and a cover disposed on the first outer wall to correspond to the sensing area. Part of the main wall is disposed between the sensing area and the terminal portion, and the main wall includes an opening through which the at least one wire passes. Other embodiments may be disclosed and/or claimed.

Provided are an optical sensor device using surface acoustic waves and an optical sensor device package. The optical sensor device includes: a substrate including a first light sensing area and a temperature sensing area and including a piezo electric material; a first input electrode and a first output electrode which are disposed in the first light sensing area and are apart from each other with a first delay gap therebetween; a first sensing film overlapping the first delay gap and configured to cover at least some portions of the first input electrode and the first output electrode; and a second input electrode and a second output electrode which are disposed in the temperature sensing area and are apart from each other with a second delay gap therebetween. The second delay gap is exposed to air.

An air data system includes an air data probe and a surface acoustic wave (SAW) sensor attached to the air data probe for detecting particulate accumulation. The air data probe includes a probe head, a strut connected to the head, and a mounting plate connected to the strut. The probe head has an inlet, an interior surface extending from the inlet, and an exterior surface extending from the inlet.

A method of interrogating an acoustic wave sensor comprises transmitting, by an interrogator, an interrogation radiofrequency signal to the acoustic wave sensor by way of a transmission antenna, receiving, by the interrogator, a response radiofrequency signal from the acoustic wave sensor by way of a reception antenna, and processing by a processing means of the interrogator the received response radiofrequency signal to obtain in-phase and quadrature components both in the time domain and the frequency domain, determining by the processing means perturbations of the obtained in-phase and quadrature components both in the time domain and the frequency domain and determining by the processing means a value of a measurand based on the detected perturbations.

An interrogation device for interrogating an acoustic wave sensor device comprises a transmission antenna; a reception antenna; and a processor configured for determining in-phase components I and quadrature components Q of a response signal received from the sensor in N consecutive frames of the response signal; determining moduli |Y| of the in-phase components I and quadrature components Q; determining a first norm M based on the moduli |Y|; determining a first weighting function W based on the first norm M and the moduli |Y|; determining in-phase components I and quadrature components Q of an N+1th frame of the response signal; determining moduli |Y| of in-phase components I and quadrature components Q of the N+1th frame; and applying the first weighting function W to the determined moduli |Y| of the response signal in the N+1th frame to obtain weighted moduli |Y|w of the response signal for the N+1th frame.