MEMS-reconfigurable metamaterials and antenna applications

This paper reviews some of our contributions to reconfigurable metamaterials, where dynamic control is enabled by micro-electro-mechanical systems (MEMS) technology. First, we show reconfigurable composite right/left handed transmission lines (CRLH-TLs) having state of the art phase velocity variation and loss, thereby enabling efficient reconfigurable phase shifters and leaky-wave antennas (LWA). Second, we present very low loss metasurface designs with reconfigurable reflection properties, applicable in reflectarrays and partially reflective surface (PRS) antennas. All the presented devices have been fabricated and experimentally validated. They operate in X- and Ku-bands.Comment: 8 pages; 8 figures; International Journal of Antennas and Propagatio

Low Loss MEMS-Reconfigurable 1-Bit Reflectarray Cell With Dual-Linear Polarization

We present a X-band 1-bit reconfigurable reflectarray (RRA) cell capable of independent reflection phase control of each linear component of a dual-polarized wave. It presents the lowest loss ever reported in an operational RRA cell at microwave frequencies, thanks to particular design considerations and implementation in a monolithic micro-electromechanical systems (MEMS) process. The average reflection loss, including oblique incidence up to theta = 40 degrees, is below 0.6 dB at the operating frequency. Low phase error and loss are preserved in a 12.5% bandwidth. Measurements demonstrate the viability of the concept as well as very good agreement between simulated and measured results

Array-Fed Partially Reflective Surface Antenna With Independent Scanning and Beamwidth Dynamic Control

In this communication we present a concept of a partially reflective surface (PRS) antenna capable of independent beam-scanning and beamwidth dynamic control. The beamwidth is controlled by reconfiguring the PRS reflectivity via embedded varactor diodes, while the beam is steered by using a small phased array in the H-plane as a source antenna exciting the Fabry-Perot cavity. A fully operational prototype is fabricated and measured upon reconfiguration, demonstrating the viability of the concept and good agreement between simulated and measured results. The achieved beamwidth variation is from 18.7 degrees to 22.4 degrees, with the scanning range of 15 degrees and 20 degrees for the narrowest and the widest beamwidth, respectively

A Simple Reflectarray Cell with 1-bit Phase Control and Polarization Flexibility

In this work we present a simple reconfigurable reflectarray (RRA) unit cell general topology and implementation, which allows the independent control of the phase and polarization of the reflected electromagnetic wave. The 1-bit phase control (with 180 degrees step) and the polarization selection between two orthogonal linear polarizations is achieved by means of only two switches embedded in the RRA cell, hence very low complexity. The good performance of the cell under oblique incidence is also demonstrated

Partially reflective surface antenna with dynamic beamwidth control

The dynamic control of the beamwidth of a partially reflective surface (PRS) antenna is reported for the first time. First, a design methodology is proposed by revisiting the PRS antenna theory from the perspective of its reconfigurable beamwidth operation, which is achieved by the control of the reflection magnitude of the PRS. The proposed PRS design only requires one varactor diode per PRS unit cell and a common control voltage for the entire structure. Finally, a fully operational reconfigurable antenna has been fabricated and measured, successfully demonstrating the targeted capability