[IEEE IEEE Antennas and Propagation Society International Symposium. 1999 Digest - Orlando, FL, USA (11-16 July 1999)] IEEE Antennas and Propagation Society International Symposium. 1999 Digest. Held in conjunction with: USNC/URSI National Radio Science Meeting (Cat. No.99CH37010) - Effect of radar polarizations on detectability of debris on roads at millimeter-wave frequencies