Wideband Filtering Slot Antenna Design with Stable Gain Using Characteristic Mode Analysis

Abstract

A filtering slot antenna with a simple structure combination using characteristic mode analysis (CMA) is proposed. To realize filtering characteristics, characteristic magnetic currents of line and ring slots are analyzed and designed. Then, the folding-line slot and double-ring slot are selected to realize radiation null separately and combined to construct the basic slot antenna. By properly exciting the selected characteristic modes, a wide filtering bandwidth and a stable gain are obtained. To validate the design process, a prototype antenna with a finite ground plane of about 1.1 λ × 1.1 λ is designed and fabricated. Simulated and measured results agree well, which both show a sharping roll rate in the lower and higher frequency and a flat gain realization in the pass band. The filtering bandwidth is 32.7%, the out-of-band suppression level at the higher frequency is over 20 dB, and the gain in the working frequency varies from 3.9 to 5.2 dB.

Research on the electromagnetic characteristics of metasurfaces based on air dielectric substrates

“…[19][20][21][22][23] Characteristic mode analysis (CMA) is widely applied in the design of metasurface antennas. [24][25][26][27][28] It can effectively assist designers in analyzing the current distribution of metasurface metal units, the frequency range of modal significance (MS), and providing a theory for the design of wideband and reconfigurable antennas. The wideband low-profile horizontally polarized omnidirectional metasurface antenna proposed in Ref.…”

A Frequency-Reconfigurable Filtenna for GSM, 4G-LTE, ISM, and 5G Sub-6 GHz Band Applications

“…However, filters increase insertion loss and the device’s size [ 4 ]. This has led to the realization of antennas with the inbuilt filters (filtennas) using cutting slits/slots, band rejection cells, defected ground structure, and electromagnetic bandgap structures to make the system more compact and efficient [ 5 , 6 , 7 , 8 , 9 ].…”

Development of Metamaterial Inspired Non-Uniform Circular Array Superstate Antenna Using Characteristic Mode Analysis

“…The characteristic mode analysis (CMA) furnishes an in-depth physical insight into the antenna design aspect and its radiating properties. In recent years, using characteristic mode analysis, different types of antennas are designed for various commercial and military communication applications, such as ultra-wideband antennas [20][21][22] and metasurface antennas [23][24][25]. In [26], a novel miniaturized metasurface unit cell is proposed, and using this miniaturized unit cell, a 4 × 4 array antenna structure is composed.…”