Design of a 5 bit digital phase shifter for 1.27 GHz phased array L-Band SAR

Abstract

PALSAR (Phased Array L-Band SAR) is a kind of L-Band SAR (Synthetic Aperture Radar) with each antenna in the system is varied by its phase to improve its performance. The PALSAR works in 1.27 GHz with varying bandwidth according to specified PALSAR system. Phased shifter is used to control each antenna's phase. Phase shifter is designed for specified frequency to reach better performance than usual phase shifter. In this paper, 5 bit digital phase shifter for L-Band SAR is designed using delay line topology and PIN diode switches. The result shows RMS error less than 2°, return loss more than 10 dB and insertion loss less than 0.8 dB.