Harmonic Radar

Abstract from US Patent 7,145,453

A method for detecting a latent environmental effect (such as a corrosive environment under insulation) or a latent structural change (such as a crack in a concealed structural member) at a known remote concealed location. The method of the instant invention includes three steps. The first step is to use a harmonic electromagnetic transponder at the known remote concealed location of the latent environmental effect or the latent structural change, the harmonic electromagnetic transponder having a reactive portion which reacts to the latent environmental effect or latent structural change to modify the harmonic emission of the transponder. The second step is to remotely interrogate the transponder by directing electromagnetic radiation at the transponder. The third step is to use the harmonic emission of the transponder to remotely determine the latent environmental effect or the latent structural change.

Publications

M. A. Volz, B. Crowgey, G. L. Charvat, E. Rothwell, L. Kempel, E. Liening, M. Warren, “Recent Developments in Miniaturized Planar Harmonic Radar Antennas.” Boston Massachusetts: Antenna Measurement and Techniques Association Conference, November 2008.

M. A. Volz, G. Charvat, L. Kempel, M. Warren, E. Liening. "Harmonic Radar Planar Antenna Miniaturization." Ottawa, Ontario: North American Radio Science Meeting, July 2007.

G. L. Charvat, L. C. Kempel.  “Harmonic Radar Tag Measurement and Characterization.”  Columbus Ohio:  IEEE Antennas and Propagation Conference, June 2003.

    Slides from this conference: IEEE/APS Society 2003