Frequency Tunable Patch Antenna Research Articles

RCS-reduced patch antenna with wide frequency tuning range based on absorbing metasurface

A frequency-tunable patch antenna with reduced radar cross section (RCS) based on absorbing metamaterial is proposed. By controlling the external voltage of the varactor diodes, the working frequency of the patch can be adjusted. Through an investigation of the composite structure of the patch and absorbing metamaterial, RCS reduction is achieved over the entire wide tunable frequency range of the antenna. Measured results illustrate that the proposed patch antenna can dynamically operate in the range from 2.28 to 3.6 GHz with a gain variation of 7.1–8.7 dBi. Meanwhile, the RCS can be reduced by at least 7 dB and up to 20 dB in a fractional bandwidth of 44.9% of the antenna under a normal incidence. In comparison to conventional RCS-reduced antennas, the proposed one features a broader frequency tuning range and has potential value in wideband radar systems under complex electromagnetic interference environments.

Wormhole Network Imaging in Post-Chops Process Using Ground-Penetrating Radar

In this study, an integrated near-field GPR system (INFGPRs) with a frequency tunable patch antenna was developed to investigate wormholes in oil sand that emerge during CHOPS. 3-dimension imaging of wormholes was then obtained based on INFGPRs through step-scanning against the wall of inspection wells. The feasibility and availability of the developed GPR system were identified through bench-scale simulation in the lab. In addition, a factorial factor experiment was designed in order to reveal the interaction effects of impact factors (depth, size, and content of wormhole) on the performance of the developed GPR system.

Computational investigation of power efficient plasma‐based reconfigurable microstrip antenna

A cold plasma-based re-configurable rectangular microstrip antenna has been computationally investigated. A power efficient frequency tunable patch antenna design is proposed wherein the substrate is replaced by a combination of air and plasma slots. The novel design consisting of plasma elements in localised regions achieves good tunability with minimal power requirements. Significant amount of frequency reconfigurability is achieved by varying the plasma density and slot configuration. A parametric study comparing the approximate power requirements and tunability of different designs has been presented. Finally the radiation properties of the proposed microplasma-based microstrip antenna has been evaluated.