Passive environmental sensing
First Claim
1. A passive sensor for monitoring an environmental condition, comprising:
- an antenna;
a modulating circuit coupled to the antenna by a microstrip transmission line, the modulating circuit capable of modulating a backscattered signal;
a sensing material disposed between the microstrip transmission line and a ground plane of the passive sensor, where an electrical property of at least a portion of the sensing material varies with the environmental condition; and
where the modulated backscattered signal includes at least one of phase and amplitude information corresponding to the electrical property of the portion of the sensing material.
1 Assignment
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Accused Products
Abstract
Various sensors, systems, and methods for monitoring environmental conditions are provided. In one embodiment, among others, a passive sensor includes an antenna; a modulating circuit coupled to the antenna by a microstrip transmission line, the modulating circuit capable of modulating a backscattered signal; a sensing material disposed between the microstrip transmission line and a ground plane of the passive sensor, where an electrical property of at least a portion of the sensing material varies with the environmental condition; and where the modulated backscattered signal includes at least one of phase and amplitude information corresponding to the electrical property of the portion of the sensing material.
18 Citations
18 Claims
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1. A passive sensor for monitoring an environmental condition, comprising:
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an antenna; a modulating circuit coupled to the antenna by a microstrip transmission line, the modulating circuit capable of modulating a backscattered signal; a sensing material disposed between the microstrip transmission line and a ground plane of the passive sensor, where an electrical property of at least a portion of the sensing material varies with the environmental condition; and where the modulated backscattered signal includes at least one of phase and amplitude information corresponding to the electrical property of the portion of the sensing material. - View Dependent Claims (2, 3, 4, 5, 6, 7, 8, 9, 10, 11)
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12. A method for monitoring an environmental condition, comprising:
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transmitting a plurality of radio signals to a passive sensor comprising a sensing material affected by the environmental condition, each of the plurality of radio signals transmitted at a different predefined frequency within a frequency range; receiving a plurality of backscattered signals from the passive sensor, each of the backscattered signals returned in response to one of the plurality of transmitted radio signals; and determining the environmental condition based on phase and amplitude information contained in the plurality of backscattered signals. - View Dependent Claims (13, 14, 15, 16, 17, 18)
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Specification