Patent ID: 7253641

Claim:
A particulate sensing system for a particulate trap comprising: a radio frequency transmit circuit including: a wideband signal generator for producing a wideband radio frequency signal; a wideband radio frequency amplifier coupled to the wideband signal generator and configured to amplify the wideband radio frequency signal; and a transmit antenna coupled to the wideband radio frequency amplifier and configured to propagate the wideband radio frequency signal through a particulate filter medium; a radio frequency receive circuit including: a receive antenna configured to receive the wideband radio frequency signal that has been propagated through the filter medium; a bandpass filter coupled to the receive antenna and configured to limit a frequency range of the received wideband radio frequency signal; and a radio frequency power sensing device coupled to the bandpass filter and configured to sense a power level of the received wideband radio frequency signal and configured to output a direct current voltage proportional to the total power received across an operating frequency range of the radio frequency power sensing device.