scholarly journals Recent Developments of Reflectarray Antennas for Reconfigurable Beams Using Surface-Mounted RF-MEMS

2012 ◽  
Vol 2012 ◽  
pp. 1-12 ◽  
Author(s):  
Eduardo Carrasco ◽  
Mariano Barba ◽  
Manuel Arrebola ◽  
Jose A. Encinar
Keyword(s):  
Phase Shifter ◽  
Rf Mems ◽  
Low Cost ◽  
Phase Control ◽  
Electronic Control ◽  
Delay Lines ◽  
Mems Switches ◽  
Manufacturing Complexity ◽  
Recent Developments ◽  
Control Devices

Some of the most recent developments in reconfigurable reflectarrays using surface-mounted RF-MEMS, which have been developed at the Universidad Politécnica de Madrid, are summarized in this paper. The results include reconfigurable elements based on patches aperture-coupled to delay lines in two configurations: single elements and gathered elements which form subarrays with common phase control. The former include traditional aperture-coupled elements and a novel wideband reflectarray element which has been designed using two stacked patches. The latter are proposed as a low cost solution for reducing the number of electronic control devices as well as the manufacturing complexity of large reflectarrays. The main advantages and drawbacks of the grouping are evaluated in both pencil and shaped-beam antennas. In all the cases, the effects of the MEMS switches and their assembly circuitry are evaluated when they are used in a 2-bit phase shifter which can be extended to more bits, demonstrating that the proposed elements can be used efficiently in reconfigurable-beam reflectarrays.

Scope of RF MEMS Technology for Microwave Circuits and Systems

2021 ◽  
pp. 1-22
Author(s):  
Kanthamani Sundharajan
Keyword(s):  
Rf Mems ◽  
Low Cost ◽  
Microwave Circuits ◽  
Micro Electro Mechanical Systems ◽  
Mems Switches ◽  
Phased Array Antennas ◽  
Array Antennas ◽  
Rf Mems Switches ◽  
Mems Technology ◽  
Key Issues

Micro-electro mechanical systems (MEMS) technology has facilitated the need for innovative approaches in the design and development of miniaturized, effective, low-cost radio frequency (RF) microwave circuits and systems. This technology is expected to have significant role in today's 5G applications for the development of reconfigurable architectures. This chapter presents an overview of the evolution of MEMS-based subsystems and devices, especially switches and phased array antennas. This chapter also discusses the key issues in design and analysis of RF MEMS-based devices, particularly with primary emphasis on RF MEMS switches and antennas.

scholarly journals Electrically Tunable Hydrogen-Bonded Liquid Crystal Phase Control Device

2018 ◽  
Vol 8 (12) ◽  
pp. 2478 ◽  
Author(s):  
Ryota Ito ◽  
Michinori Honma ◽  
Toshiaki Nose
Keyword(s):  
Liquid Crystal ◽  
Phase Shifter ◽  
Continuous Wave ◽  
Phase Control ◽  
Terahertz Wave ◽  
Control Device ◽  
Absorption Properties ◽  
Control Devices ◽  
Wave Control ◽  
Hydrogen Bonded

Terahertz waves have attracted much attention mainly because of their potential in imaging, security checking, nondestructive testing, and information and communication technologies. In the past few years, there has been an extensive effort to investigate terahertz wave control devices. Liquid crystal (LC) devices are strong candidates for high-performance terahertz wave control devices because of their controllability at low drive voltages and their low power consumption. In this study, we fabricated an electrically tunable phase control device by using a hydrogen-bonded LC material. We investigated the performance of the LC phase shifter by using a far infrared continuous wave laser. We also estimated the birefringence and absorption properties of the hydrogen-bonded LC at 2.5 THz by using Jones matrix calculations. The measurements and calculation results indicated that the hydrogen-bonded LC showed no dichroism at 2.5 THz. Based on the absorption properties, we believe that it could be a strong candidate for use in future terahertz devices.

Packaged single pole double thru (SPDT) and true time delay lines (TTDL) based on RF MEMS switches

2008 ◽  
Author(s):  
Giorgio De Angelis ◽  
Andrea Lucibello ◽  
Romolo Marcelli ◽  
Simone Catoni ◽  
Antonio Lanciano ◽  
...  
Keyword(s):  
Time Delay ◽  
Rf Mems ◽  
Delay Lines ◽  
Mems Switches ◽  
True Time Delay ◽  
Rf Mems Switches ◽  
True Time

Micro/Nanotribology of RF MEMS Switches

2004 ◽  
Author(s):  
Steven T. Patton ◽  
Kalathil C. Eapen ◽  
Jeffrey S. Zabinski
Keyword(s):  
Electric Current ◽  
Microelectromechanical Systems ◽  
Rf Mems ◽  
Low Cost ◽  
Operating Conditions ◽  
Great Promise ◽  
Rf Switches ◽  
Mems Switches ◽  
Adhesion Contact ◽  
Rf Mems Switches

Microelectromechanical systems (MEMS) radio frequency (RF) switches hold great promise in a myriad of commercial, aerospace, and military applications. MEMS switches offer important advantages over current electromechanical and solid state technologies including high linearity, low insertion loss, low power consumption, good isolation, and low cost [1–21]. However, there is little fundamental understanding of the factors determining the performance and reliability of these devices. Our previous work investigated fundamentals of hot-switched direct current (DC) gold (Au) contacts using a modified microadhesion apparatus as a switch simulator [1]. Those experiments were conducted under precisely controlled operating conditions in air at MEMS-scale forces with an emphasis on the role of surface forces and electric current on switch performance, reliability, and durability [1]. Electric current had a profound effect on deformation mechanisms, adhesion, contact resistance (R), and reliability/durability. At low current (1–10 μA), asperity creep and switching induced adhesion were the most important observations, whereas, at high current (1–10 mA), lack of adhesion and switch shorting by nanowire formation were prominent [1].

A 60-GHz 2-bit Switched-Line Phase Shifter Using SP4T RF-MEMS Switches

2011 ◽  
Vol 59 (4) ◽  
pp. 894-900 ◽  
Author(s):  
Songbin Gong ◽  
Hui Shen ◽  
N. Scott Barker
Keyword(s):  
Phase Shifter ◽  
Rf Mems ◽  
60 Ghz ◽  
Mems Switches ◽  
Rf Mems Switches

Photodefinable Metal Oxide Dielectrics: A Novel Method for Fabricating Low Cost RF Capacitive MEMS Switches

2003 ◽  
Vol 783 ◽  
Author(s):  
Guoan Wang ◽  
Augustin Jeyakumar ◽  
John Papapolymerou ◽  
Clifford L. Henderson
Keyword(s):  
Dielectric Constant ◽  
Metal Oxide ◽  
Rf Mems ◽  
High Dielectric Constant ◽  
Low Cost ◽  
Organic Precursor ◽  
Mems Switches ◽  
Novel Approach ◽  
Capacitive Mems ◽  
High Dielectric

ABSTRACTIn this paper, a novel approach for fabricating low cost capacitive RF MEMS switches using directly photodefinable high dielectric constant metal oxides has been developed. In this approach, a radiation sensitive metal-organic precursor is deposited via spin coating and converted patternwise to a high dielectric constant metal oxide via ultraviolet exposure. The feasibility of this approach is demonstrated by fabricating bridge-type and cantilever-type switches with a nitride/metal-oxide/nitride dielectric film stack. These switches exhibited significantly higher isolation and load capacitances as compared to comparable switches fabricated using a simple silicon nitride dielectric.

Photodefinable Metal Oxide Dielectrics II: Direct Fabrication of Patterned High-k Dielectrics for Low Cost RF Capacitive MEMS Switches

2004 ◽  
Vol 833 ◽  
Author(s):  
Michael Romeo ◽  
Isaac Finger ◽  
Augustin Jeyakumar ◽  
Guoan Wang ◽  
John Papapolymerou ◽  
...  
Keyword(s):  
Metal Oxide ◽  
Metal Oxides ◽  
Oxygen Plasma ◽  
Rf Mems ◽  
Dielectric Breakdown ◽  
Low Cost ◽  
Dielectric Constants ◽  
Mems Switches ◽  
Rf Mems Switches ◽  
Metal Organic

ABSTRACTIn this paper, recent advancements related to a novel approach for fabricating low cost capacitive radio frequency microelectromechanical (RF MEMS) switches using directly photodefinable high dielectric constant metal oxides are discussed. In this approach, a radiation sensitive metal-organic precursor is deposited via spin coating and converted patternwise to a metal oxide using exposure to ultraviolet light. The feasibility of this approach has previously been demonstrated by fabricating bridge-type and cantilever-type RF MEMS switches. These early experiments showed that the photopatterned oxides displayed dielectric breakdown strengths that were insufficient for reliable operation of MEMS switches which required actuation voltages on the order of 20 V to 30 V. Recent work has focused on developing advanced processes based on the photodefinable metal-organic approach that can produce oxides with higher dielectric breakdown strengths and higher dielectric constants. A variety of post-patterning processes, including thermal baking and oxygen plasma annealing, were investigated and the impact of such processing on the resulting dielectric properties are discussed in this paper. It is shown that a combination of thermal annealing and oxygen plasma treatment can substantially improve the dielectric breakdown strength of the metal oxides produced using the photosensitive metal-organic process.

scholarly journals Laterally Movable Triple Electrodes Actuator toward Low Voltage and Fast Response RF-MEMS Switches

Sensors ◽  
2019 ◽  
Vol 19 (4) ◽  
pp. 864 ◽  
Author(s):  
Yasuyuki Naito ◽  
Kunihiko Nakamura ◽  
Keisuke Uenishi
Keyword(s):  
Rf Mems ◽  
Low Voltage ◽  
Low Cost ◽  
Actuation Voltage ◽  
Fast Response ◽  
Point Of View ◽  
Micro Electro Mechanical Systems ◽  
Mems Switches ◽  
Rf Mems Switches ◽  
Series Switch

A novel actuator toward a low voltage actuation and fast response in RF-MEMS (radio frequency micro-electro-mechanical systems) switches is reported in this paper. The switch is comprised of laterally movable triple electrodes, which are bistable by electrostatic forces applied for not only the on-state, but also the off-state. The bistable triple electrodes enable the implementation of capacitive series and shunt type switches on a single switch, which leads to high isolation in spite of the small gap between the electrodes on the series switch. These features of the actuator are effective for a low voltage and fast response actuation in both the on- and off-state. The structure was designed in RF from a mechanical point of view. The laterally movable electrodes were achieved using a simple, low-cost two-mask process with 2.0 µm thick sputtered aluminum. The characteristics of switching response time and actuation voltage were 5.0 µs and 9.0 V, respectively.

Sign in / Sign up

Export Citation Format

Share Document