Patent ID: 7959136

Claim:
A vehicle system comprising: an air spring including a first member and a second member spaced a distance from said first member; a transceiver and first antenna associated with said first member, said transceiver configured to broadcast an electromagnetic wave using said first antenna; a transponder and second antenna associated with said second member, said transponder and said second antenna configured to receive said electromagnetic wave, said transponder configured to short circuit said second antenna for a predetermined period to induce an amplitude variation of said electromagnetic wave, said amplitude variation changing as a distance from said first antenna to said second antenna changes, said transponder configured to receive a sensor output signal, and said transponder configured to cause a modulation of said electromagnetic wave in relation to said output signal; and, said vehicle system configured to detect and measure said amplitude variation of said broadcasted electromagnetic wave, correlate a specific amplitude variation with a respective distance from said first antenna to said second antenna, and generate a signal representative of said respective distance.