Low‐loss compact MEMS phase shifter for phased array antennas

Abstract

A compact and low-loss MEMS-based phase shifter is proposed for microwave/millimetre-wave phased array antenna systems. The proposed phase shifter is an alumina-based CPW line, loaded with a variable series capacitor. The phase shifter uses an electromagnetic MEMS actuator to change the capacitor value. A simple three-mask surface micromachining process has been developed for device fabrication. The measurements at 26 GHz show a phase shift of 20°. The overall size of the phase shifter (including the actuator) is 0.5 × 1.5 mm. The measured average insertion loss is 0.75 dB with a variation of 0.4 dB for different phase shifts across the band from 24.5 to 26.5 GHz.

Design and characterization of compact digital RF MEMS capacitors and phase shifters in CMOS 0.35 µm technology

“…The HFSS electromagnetic simulation results in figure 14 show that the maximum insertion loss variation of the phase shifter over the 20 GHz operation bandwidth is around 1 dB, which is relatively good in comparison with the results reported in [19][20][21]. Additionally, the insertion loss is comparable with bulky MEMS phase shifters designed using conventional surface micromachining fabrication processes.…”

“…This is the same value that was used in the HFSS electromagnetic simulation shown in figures 14 and 15 for the insertion loss and phase angle, respectively. Among the most important performance parameters for the design of phase shifters is the absolute insertion loss, and insertion loss variation [20,21]. For different phase values at different states of the device, it is always desirable to maintain the insertion loss at the same value for all states, i.e.…”

BD‐SBA for wireless backhauling application

“…The phased array antennas have high gains and can be used as a candidate for beam‐deflection antennas. However, the phased array antennas need a lot of phase shifters to achieve beam controlling, which leads to complicated fabrication process, high cost and huge volume, limiting its massive application for wireless backhauling [4]. The short backfire antenna (SBA) is a type of directional antenna, which has a high gain, a high aperture efficiency, a small sidelobe level (SLL) and a low cost [5].…”

Monolithic integrated MEMS phased array antenna scanning in two dimensions

“…However, because of the complexity, large volume and high cost, the further application in some special area has been limited, such as in space and in ammunition [1,2]. RF MEMS phase shifters and switches, as the critical elements in PAAs, which have exhibited excellent characteristics including small volume, low insertion loss and low dc power consumption compared to the GaAs based MMIC counterparts, have been demonstrated in [3,4,5]. With the advent of RF MEMS phase shifters and switches, there should be considerable business interests in the development of MEMS-based phase array antenna.…”