Planar antenna-coupled detector for matrix systems of millimeter wave imaging

Planar detector as a microstrip slot antenna loaded directly by a low barrier Schottky diode was under consideration. Modified slot antenna with high directivity, radiation resistance -800 Omega and good matching with detector diodes at resonance frequency 94 GHz was developed. The main characteristics of planar detectors were measured. It was demonstrated that the maximum of rf-to-dc voltage sensitivity gamma > 10000 V/W. Frequency band of the detector was about 8 GHz (at -3 dB level). The best value of the noise equivalent power NEP ap 10^-12 W Hz^-1/2 was predicted. Interaction effects in a row of close located planar antennas were investigated. Reduction of interaction by mounting additional shielding pins on a screen was studied. The possibility of the compact arrangement of planar detectors with the period of 3 / 2lambda was shown.