W-Band Polarimetric Monopulse Tracking Receiver

摘要

A planar 94 GHz monopulse receiver has been integrated on a single chip. The receiver is based on four planar antennas followed by four planar subharmonic mixers. The output of the mixers is taken to an IF monopulse processor at 2-4 GHz so as to achieve very deep nulls. The performance of the monopulse receiver has been measured at 94 GHz and resulted in a system NF of around 15 dB, and better than -40 dB nulls in the elevation and difference patterns. Furthermore, the null is maintained at lower than -20 dB over 2 GHz bandwidth. This represents the highest performance monopulse receiver to-date in a planar implementation and is competitive with waveguide systems at W-band frequencies. Also, we have developed novel distributed wideband MEMS phase shifters suitable for 2-100 GHz applications. The distributed MEMS phase shifters resulted in excellent performance at 40-100 GHz. with an insertion loss of better than 4 dB for a 360 deg. phase shift. To our knowledge. this represents the best phase shifter performance at these frequencies using any technology (diode, HEMT, MEMS).