A novel technique to measure the input impedance of on-chip microstrip patch antenna in standard CMOS technology

Abstract

This paper describes a novel technique to measure the input impedance of on-chip microstrip patch antenna in standard CMOS technology. By using the measured impedance of IMPATT diodes fabricated in the same standard CMOS technology and three lateral IMPATT diodes integrated with a microstrip patch antenna at one of the radiating edges, oscillation can be achieved and accurate measurement of the antenna input impedance can be extracted. The antenna used is 1.4mm2 and it is designed at 77GHz by using the high frequency electromagnetic field solver Sonnet. The detected oscillation observed in the range of 75∼77GHz, with transmitted power of −62dBm at 77GHz. The measured input impedance is within 10% of the simulated one. It is hoped that this technique will provide accurate method to measure the input impedance in the millimeter-wave range of on-chip antenna with minimum near-filed perturbation.