@article{kilgore_kabiri_kane_steer_2016, title={The Effect of Chaotic Vibrations on Antenna Characteristics}, volume={15}, ISSN={["1548-5757"]}, DOI={10.1109/lawp.2015.2503264}, abstractNote={The radio signal transmitted from a vibrating antenna is modulated producing spectral content that can interfere with a nearby receiver. The additional spectral content is centered at the transmitted RF signal, and with chaotic vibrations, the spectrum has significant content beyond the fundamental frequency of vibration. Thus, the effect of vibration on co-site interference is much greater than expected. A controlled experiment using a monopole antenna driven at 900 MHz and vibrating at 150 Hz has significant RF spectral content extending to 5 kHz.}, journal={IEEE ANTENNAS AND WIRELESS PROPAGATION LETTERS}, author={Kilgore, Ian M. and Kabiri, Shabir A. and Kane, Andrew W. and Steer, Michael B.}, year={2016}, pages={1242–1244} }
 @article{wilkerson_kilgore_gard_steer_2015, title={Passive Intermodulation Distortion in Antennas}, volume={63}, ISSN={["1558-2221"]}, DOI={10.1109/tap.2014.2379947}, abstractNote={An analytic formulation of passive intermodulation distortion (PIM) in antennas is presented for PIM introduced by electro-thermal modulation of conductivity by current-related losses. A silver rectangular patch antenna was fabricated using a sapphire substrate isolating the thermal process from other possible sources. Two-tone testing at 990 MHz using a sweep of the tone separation from 3 Hz to 100 kHz is reported. Both transmitted and reflected PIM are characterized using a high dynamic range two-tone test system incorporating an analog canceler achieving a dynamic range of 125 dB at 1-Hz tone separation for reflection measurements, and 100 dB at 10-Hz tone separation for transmission measurements with each tone set to 32.3 dBm.}, number={2}, journal={IEEE TRANSACTIONS ON ANTENNAS AND PROPAGATION}, author={Wilkerson, Jonathan R. and Kilgore, Ian M. and Gard, Kevin G. and Steer, Michael B.}, year={2015}, month={Feb}, pages={474–482} }