Broadband Linearly Tapered Slot Antenna with Corrugated Edges for Phased Array and Multi-beam Systems

This paper reports uniplanar linearly tapered slot antennas (LTSA) with corrugated edges exhibiting wide impedance bandwidth and improved radiation patterns with experimental verification. The antenna is fed by coplanar waveguide (CPW) and the input impedance of LTSA is matched to 50 Omega CPW feed line by means of Marchand baluns. Impedance, radiation and gain characteristics of the proposed antenna both on low-index RT-Duroid and high-index silicon substrates are presented and discussed. From experimental results, the measured impedance bandwidth of the corrugated antenna developed on RT-Duroid is widened from 4 GHz to 5.5 GHz at 17 GHz. The effect of corrugation structure at the edges of silicon-LTSA is more pronounced for radiation pattern and the analytical results show modification of distorted radiation pattern into correct LTSA radiation characteristics.