This totally eliminates the need for batteries to power the sensor-transponder assembly. These units can then be left in place for an unlimited length of time with no need for periodic disassembly and battery replacement. T he microwave transponder assembly requires very little electrical power, and thus yields a much longer battery life than techniques previously available. S maller package size. A n electromagnetic frequency which is relatively unaffected by any other interference in the engine, and is actually enhanced by reflection within the cavities of the crankcase.
E asy to install.
C ontinuous data transmissions. V ery little attenuation by the engine oil in the crankcase. Uses T his technology can be used in industrial or academic research to measure piston temperatures, connecting rod temperatures, pressures behind the top piston ring, and pressures and temperatures in the torque converter of an automatic transmission. If using the alternate embodiment, and not requiring periodic battery replacement, the microwave-powered transponder technique would be useful in any instrumentation situation where the batteries are relatively inaccessible or difficult to replace, and wires cannot be used. E ither techniques could be commercialized by companies with experience in making similar measurements using an infrared carrier signal.