MEMS-Based Miniature X-Band Phase Shifters.

摘要

The focus of this work was to drive the size and insertion loss of MEMS based phase shifters to an absolute minimum. The work is based on single pole, 4-throw (SP4T) MEMS switches. These novel switches were then applied on the development of low-loss, miniature 2-bit and 4-bit phase shifters. All designs are carried out on 8-mil thick GaAs substrates, a similar substrate typically used for X-band amplifier designs. Measurements indicate an insertion loss of -0.6 dB at 10 GHz for the 2-bit design, and excellent linear phase response and return loss from DC to 18 GHz. The chip area is 9.6 mm2, and is the smallest reported to-date. The 2-bit phase shifter performed well from DC-18 GHz, with -0.8dB insertion loss at 18 GHz and a return loss of <-10.5 dB over DC-18 GHz. The 4-bit phase shifter based on SP4T switches resulted in a measured average insertion loss of -1.1 dB at 10 GHz, and a linear phase shift response from DC to 18 GHz. The chip area is 21 mm2. This is the highest performing 4-bit phase shifter to-date at X-band, using any technology.