Patent ID: 7180404

Claim:
A wireless sensor system, comprising: a reader apparatus configured to generate an induction field; a sensor apparatus configured to monitor structural integrity of an object, the sensor apparatus being communicatively linked to the reader apparatus and in a passive state until energized by the reader apparatus, the sensor apparatus including: processing circuitry; a resonant antenna configured to communicate data between the sensor apparatus and the reader apparatus, the resonant antenna being configured to collect energy from the induction field to energize the sensor apparatus; a plurality of sensors, the sensors being respectively configured to measure predetermined parameters of the object, and to be independently interrogated by the reader apparatus, measurements obtained by the individual sensors being transmitted via a response signal to the reader apparatus via the resonant antenna, the response signal being superimposed on the return induction field; circuitry configured to store energy collected from the induction field to provide power to the sensor apparatus, including two capacitor banks, one of the capacitor banks being configured to provide power for short-term operations and the other of the capacitor banks being configured to provide power for extended operations, and being configured to accumulate energy while measurements are being made by the plurality of sensors; and the reader apparatus including: a transceiver configured to communicate with the sensor apparatus; an antenna having a loop with a diameter above 66 inches, the loop being formed of multi-strand wires; a modem configured to selectively transfer data from the reader apparatus to a remote site; a microprocessor configured to control operations of the reader apparatus, and the individual sensors of the sensor apparatus being independently interrogated by the microprocessor, in operation.