Comprehensive Review of RF MEMS Switches in Satellite Communications

Abstract

The miniaturization and low power consumption characteristics of RF MEMS (Radio Frequency Microelectromechanical System) switches provide new possibilities for the development of microsatellites and nanosatellites, which will play an increasingly important role in future space missions. This paper provides a comprehensive review of RF MEMS switches in satellite communication, detailing their working mechanisms, performance optimization strategies, and applications in reconfigurable antennas. It explores various driving mechanisms (electrostatic, piezoelectric, electromagnetic, thermoelectric) and contact mechanisms (capacitive, ohmic), highlighting their advantages, challenges, and advancements. The paper emphasizes strategies to enhance switch reliability and RF performance, including minimizing the impact of shocks, reducing driving voltage, improving contacts, and appropriate packaging. Finally, it discusses the enormous potential of RF MEMS switches in future satellite communications, addressing their technical advantages, challenges, and the necessity for further research to optimize design and manufacturing for broader applications and increased efficiency in space missions. The research findings of this review can serve as a reference for further design and improvement of RF MEMS switches, which are expected to play a more important role in future aerospace communication systems.

Keywords: RF MEMS switches; RF performance; reconfigurable antennas; satellite communication.

Figure 1

Structures of four conventional RF MEMS switches: (a) Electrostatically actuated RF MEMS switch [25]. Reprinted/adapted with permission from [25]. Copyright 2011, with permission from Elsevier. (b) Piezoelectrically actuated RF MEMS switch [26]. Reprinted/adapted with permission from [26], 2012, IEEE. (c) Electromagnetically actuated RF MEMS switch [27]. Reprinted/adapted with permission from [27]. (d) Electrothermally actuated RF MEMS switch [28]. Reprinted/adapted with permission from [28], 2020, IEEE.

Figure 9

(a) The frequency reconfigurable capacitive shunt RF MEMES switch [142]. Reprinted/adapted with permission from [142]. Copyright 2019, with permission from Elsevier. (b) The T-match RF MEMS capacitive switch [143]. Reproduced with permission from Springer Nature. (c) The SP12T RF MEMS Switch [145]. Reprinted/adapted with permission from [145], 2018, IEEE.

Figure 2

Structures of capacitive RF MEMS switches: (a) Li et al. [51]. Reprinted/adapted with permission from [51]. Copyright 2016, with permission from Elsevier. (b) Shi et al. [8]. Configuration diagram of flexible RF MEMS switch in different modes: (i) On state and (ii) Off state of MEMS switch with flat substrate; (iii) On state and (iv) Off state of MEMS switch with curved substrate. Reprinted/adapted with permission from [8].

Figure 3

Structures of ohmic RF MEMS switches: (a) Bansal et al. [68]. Reprinted/adapted with permission from [68], 2019, IEEE. (b) Bajwa et al. [9]. Reprinted/adapted with permission from [9].

Figure 4

(a) Schematics of three designs of capacitive RF MEMS switches. (i) Design 1: T-support, (ii) Design 2: parallel-support, and (iii) Design 3: L-support beams [90]. Reprinted/adapted with permission from [90], 2017, IEEE. (b) Illustration of the nonlinear command shapers for electrostatically actuated MEMS systems. (i) Two-step nonlinear shaping method for positioning and (ii) shaper for contact force minimization [93]. Reprinted/adapted with permission from [93], 2011, IEEE. (c) Soft-landing by patterning the electrode upper/lower or dielectric. Electrode upper/lower can be a (p1) rectangular plate, (p2) array of cylinders, or (p3) array of spheres, and dielectric can be (p4) an array of linear slots or (p5) a fractal of linear slots [88]. Reprinted from [88], with the permission of AIP Publishing.

Figure 5

Structures of graphene MEMS devices: (a) Bunch et al. [112]. From [112]. Reprinted with permission from AAAS. (b) Kim et al. [113]. Reprinted from [113], with the permission of AIP Publishing. (c) Zhang et al. [70]. Reprinted from [70]. Copyright 2023, with permission from Elsevier.

Figure 6

Atomic-scale contact–separation simulation using DFT calculations. [122] (a) DFT-optimized atomic structures of the gold (Au) tip and nickel (Ni) surface; (b) calculated atomic force of the Au tip, $F_{tip}$ Ftip, during approach (left) and retraction (right). $F_{tip}$ fluctuates considerably and gradually recovers during approach and retraction, respectively, because of the rearrangement of Au atoms, resulting in significant hysteresis; (c) DFT-optimized atomic structures of the Au tip and graphene (Gr)-coated surface; (d) calculated $F_{tip}$ Ftip during approach (left) and retraction (right). Reprinted/adapted with permission from [122].

Figure 7

(a) Top view of switch with series protection contact [123]. Reprinted/adapted with permission from [123], 2016, IEEE. (b) Top view of the shunt-protected switch [124]. Reprinted/adapted with permission from [124], 2017, IEEE. (c) The structure of the compact single-cantilever multicontact switch [125]. Reprinted/adapted with permission from [125], 2018, IEEE. (d) The structure of levitation-based micro-switch [126]. Reproduced with permission from Springer Nature. (e) The structure of a non-contact-type switch [127]. Reprinted/adapted with permission from [127], 2009, IEEE. (f) The structure of a three-state contactless switch [128]. The inset shows the initial gap between the signal lines and grounded movable electrodes. Reprinted/adapted with permission from [128], 2015, IEEE.

Figure 8

(a) Proposed wafer-level packaging approach for RF MEMS devices using BCB bonding [131]. Reprinted/adapted with permission from [131], 2019, IEEE. (b) Schematic of the ohmic RF MEMS with a zoom on vias connecting the CPW line to the probing pads outside the seal ring [135]. Reprinted/adapted with permission from [135], 2022, IEEE. (c) Layout and dimensions of the zero-level packaged RF MEMS switched capacitors [136]. Reprinted/adapted with permission from [136], 2020, IEEE. (d) Top view of a SPST switch including TFP encapsulation [72]. Reprinted/adapted with permission from [72], 2017, IEEE.

Figure 10

(a) The dual-warped-beam switch [152]. Reprinted/adapted with permission from [152], 2010, IEEE. (b) The composite metal-dielectric warped membranes [153]. Reprinted/adapted with permission from [153], 2009, IEEE.

Figure 11

A 3D schematic view of serial-shunt switches: (a) Khodapanahandeh et al. [157]. A, B, and C represent different pads, and the state of the switch is controlled by adjusting their voltages. Reprinted/adapted with permission from [157], 2022, IEEE. (b) Singh [158]. Reproduced with permission from Springer Nature. (c) Zhu et al. [42]. Reprinted/adapted with permission from [42]. Copyright 2014, with permission from Elsevier.

Figure 12

An example of a transceiver that supports different frequency bands [159]. Reprinted/adapted with permission from Ref [159], 2022, John Wiley and Sons.

Figure 13

(a) The MEMS-modulated scanning antenna [174]. Reprinted/adapted with permission from [174], 2016, IEEE. (b) Optimized E-shaped patch antenna with RF MEMS switches [175]. Reprinted/adapted with permission from [175], 2014, IEEE. (c) Photograph of the antenna and its MEMS biasing network [178]. Reprinted/adapted with permission from [178], 2016, IEEE. (d) The novel multiple-beam antenna for satellite applications [168]. Reproduced courtesy of the Electromagnetics Academy.