Patent ID: 7399280

Claim:
A fluid flow sensing system, comprising: a piezoelectric substrate; a surface acoustic wave flow sensor for monitoring a flow of fluid through a cylindrically-shaped compartment formed from a plurality of walls, said surface acoustic wave flow sensor comprising at least one upstream surface acoustic wave sensing device and at least one downstream surface acoustic wave sensing device, said surface acoustic wave flow sensor comprising at least one interdigital transducer and a self-heating heater formed upon said piezoelectric substrate wherein said self-heating heater is disposed between said at least one upstream surface acoustic wave sensing device and said at least one downstream surface acoustic wave sensing device, said interdigital transducer comprising an electrode material that is selected to convert negligible electrical coupling to surface waves thereof; a first antenna connected to said self-heating heater to receive RF energy wherein said self-heating heater absorbs said RF energy and converts said RF energy to heat; and a second antenna integrated with said at least one interdigital transducer, wherein said second antenna receives at least one signal, which excites said at least one interdigital transducer to produce a frequency output associated with said flow of said fluid for analysis thereof.