Free Space Measurement Method with Parallel Electromagnetic Wave Beam by Using Dielectric Lenses and Horn Antennas for Reflectivity of Electromagnetic Absorbers in Millimeter Waves. - Hirosuke Suzuki; Atsuhiro Nishikata; Yutaka Higashida; Tetsu Soh; Osamu Hashimoto (IEICE Trans. Electron., 2006)