Currently, one of the main trends in the development of next-generation communication systems is the use of a modern component base, specifically, the construction of microwave devices based on microsystem technology. Designing devices using microsystem technology makes it possible to improve performance characteristics, particularly in terms of reducing insertion loss and increasing the accuracy of signal phase setting. One of the key elements of next-generation communication systems is the phase shifter. Designing a phase shifter based on a MEMS varactor, which consists of a combination of MEMS switches, will enable the creation of a device with equivalent parameters without the need for delay lines, which have large dimensions at low operating frequencies. Furthermore, its control becomes digital. The values of the “digital capacitance” can be calculated in such a way that the phase adjustment of the phase shifter follows the classical principles for a delay line-based phase shifter—ranging from 0 to 360 deg with a step size dependent on the phase shifter’s bit resolution. Implementing the phase shifter based on a microwave MEMS varactor with “digital capacitances” will allow the entire phase shifter structure to be fabricated in a unified technological process based on microsystem technology, thereby reducing production costs.
Dryagin et al. (2025) studied this question.