Patent ID: 7364144

Claim:
An air spring assembly comprising: a first end member; a second end member spaced a distance from said first end member and undergoing an external input; a flexible wall secured between said first and second end members; a transceiver and first antenna associated with the said first end member and broadcasting an electromagnetic wave using said first antenna; a transponder and second antenna associated with said second end member, the transponder and second antenna adapted to receive said electromagnetic wave and said transponder operative to shunt the second antenna for a predetermined period, the shunted second antenna inducing an amplitude variation of said electromagnetic wave, the amplitude variation increasing as the distance from the first antenna to the second antenna decreases; and, a sensor associated with said second end member and in communication with said transponder, said sensor being adapted to measure the external input of said second end member and generate a corresponding sensor output signal; wherein the air spring assembly detects and measures the amplitude variation of said broadcasted electromagnetic wave, correlates specific amplitude variations with respective distances from the transceiver antenna to the transponder antenna, generates a signal representative of the respective distances, and said transponder receives said sensor output signal and causes a modulation of said electromagnetic wave in relation to said sensor output signal.