Abstract: A method of wirelessly interrogating a sensing device comprising a plurality of passive sensors, to determine a measurement parameter, comprises the steps of repeatedly interrogating the sensing device using a predetermined transmission signal and detecting the response; estimating the measurement parameter for each sensor by means of an analysis of the data accumulated as a result of the interrogation step, and determining the average of the parameters derived from the estimating step for each sensor, using a weighted average, in which the weightings depend on the amplitude of the sensor response. The measurement parameter may be a resonant frequency where the passive sensors are resonant devices, and the sensors may be SAW devices.

Abstract: A tire pressure monitoring system (TPMS) sensor assembly 1 has a housing 2, a pressure sensor mounted in the housing 2 and an antenna 3 connected to the sensor and extending exteriorly of the housing 2 for effecting wireless communication between the sensor and a remote module. The antenna 3 is moveable between a folded position in which it extends around at least a part of the housing 2 so as to lie substantially in the plane of the housing 2 and an erect position in which it upstands from the housing 2 so as, in use, to extend into the inflation area formed between a wheel and tire. The antenna 3 is biased towards its erect position, and further includes a releasable restraining strap 7 for restraining the antenna 3 in its folded position.

Abstract: A method of wirelessly interrogating a sensing device comprising a plurality of passive sensors, to determine a measurement parameter, comprises the steps of repeatedly interrogating the sensing device using a predetermined transmission signal and detecting the response; estimating the measurement parameter for each sensor by means of an analysis of the data accumulated as a result of the interrogation step, and determining the average of the parameters derived from the estimating step for each sensor, using a weighted average, in which the weightings depend on the amplitude of the sensor response. The measurement parameter may be a resonant frequency where the passive sensors are resonant devices, and the sensors may be SAW devices.

Abstract: The present invention relates to a method and apparatus for assessing the condition of a wheel particularly, but not exclusively, to a method and apparatus for assessing the condition of a tire rotating on a vehicle wheel. Apparatus is provided comprising a plurality of antennas (101, 102, 103, 104, 105, 106, 107, 108) for transmitting an interrogation signal to a sensor (110, 112), the sensor being mounted to a wheel to be assessed and being adapted to detect the condition of the wheel; wherein the antennas are arranged in a line along a path to be followed by a wheel to be assessed.

Abstract: A sensor mounting assembly for securing a sensor within a pressurized chamber defined between a wheel and a tire, comprises a patch 2 having a fastening surface 2a by a device in which it is securable, in use, to an inner surface of a tire or wheel. A plate 5 having a threaded aperture 4 is embedded in the patch 2. A sensor housing 1 has a threaded shaft 3 extending from it which complements the thread formed in the plate 5, so that the shaft 3 may be screwed into the aperture 4 in order to secure said housing to the exterior of the patch.

Abstract: A tire pressure monitoring system (TPMS) sensor assembly 1 has a housing 2, a pressure sensor mounted in the housing 2 and an antenna 3 connected to the sensor and extending exteriorly of the housing 2 for effecting wireless communication between the sensor and a remote module. The antenna 3 is moveable between a folded position in which it extends around at least a part of the housing 2 so as to lie substantially in the plane of the housing 2 and an erect position in which it upstands from the housing 2 so as, in use, to extend into the inflation area formed between a wheel and tire. The antenna 3 is biased towards its erect position, and further includes a releasable restraining strap 7 for restraining the antenna 3 in its folded position.

Abstract: A wheel well filler or runflat safety band having a band member with at least one break in it so as to enable it to be fitted onto a wheel. A link member connects the ends of the band member so as to bridge the break and thereby secure the band, in use, on a wheel. A wireless device is attached to the link member, which wireless device is remotely interrogatable in order to confirm the presence of the filler on the wheel.