Dual‐polarised and ultra‐thin broadband AAMCs for both P and L bands applications

Abstract

Conventional artificial magnetic conductor (AMC) suffers from the thick profile and narrow bandwidth in the lowfrequency band. Incorporating varactors into a passive AMC can adjust the working frequency dynamically and broaden the operating band range. This study investigates the different incorporation methods of varactors into AMC using the equivalent circuit analysis method. By establishing the equivalent circuit of the whole configuration, the frequency-domain working characteristics of passive AMC and active AMC (AAMC) are theoretically analysed. It reveals that a parallel incorporation of varactors allows lowering the frequency and increase the working bandwidth more efficiently when compared with a series integration. Following this principle, two dual-polarised AAMCs are proposed. Simulations and measurements indicate that both AAMCs elements have an ultra-low profile (0.0035λ) and compact size (0.04λ). Moreover, the in-phase-reflection frequency bands of both AAMCs cover P and L bands, proving the effectiveness of the proposed design method.

Design of a Low-Profile, Frequency- Reconfigurable, and High Gain Antenna Using a Varactor-Loaded AMC Ground

“…Recently, reconfigurable antennas are attracting more and more attentions because of their capability for acquiring satisfied selectivity in polarization, radiation pattern, gain, as well as operation frequency bandwidth [1]- [6]. Their tunable and steerable features make the reconfigurable antennas be suitable in wireless communication systems for multifunction applications.…”

“…In the recent years, simple sandwich type planar artificial magnetic conductor (AMC) structures, mainly consisting of periodic unit cells, have been widely investigated, because of their in-phasereflection characteristics. They have been further developed to enhance effectively the loaded antenna radiation performance [1], [4], [16]- [30], [36], [37]. In [16], an AMC with periodically arranged square patches was adopted to broaden the bandwidth for a combined antenna with loop and monopole elements.…”

Multi-Band and High Gain Antenna Using AMC Ground Characterized With Four Zero-Phases of Reflection Coefficient

“…Meanwhile, utilizing the lumped capacitors in the AMC structure will decrease the design cost of the AMC and improve its performance. In order to improve the AMC's performance in terms of operation frequency points, bandwidths, and miniaturization dimensions, the lumped capacitors or varactor diodes are often employed and embedded into the metal pattern of the AMC unit cells [20], [25], [32]. As illustrated in [20], there are four lumped capacitors used in one AMC unit cell.…”

“…As illustrated in [20], there are four lumped capacitors used in one AMC unit cell. In [25] and [32], the number of varactor diodes mounted in the one AMC unit cell is eight and one, respectively. Similarly, in this research, to generate the highest frequency band, four identical lumped capacitors are embedded in the innermost ring of the proposed FMNR-AMC unit cell.…”

A Novel Reconfigurable Metasurface with Coincident and Ultra-Wideband LTL and LTC Polarization Conversion Functions

“…The implementation of the existing reconfigurable polarization converters can be divided into two methods. One method is to change the dielectric materials [16][17][18][19][20][21], the other is to change effective metal structure by using electronic devices [22][23][24][25][26][27][28][29][30][31][32][33]. The former method uses materials such as liquid crystals [16], graphene [17], [18], metal fluid [19], [20], vanadium oxide (VO 2 ) film [21] to replace the traditional metal and dielectric materials, this method has the characteristics of high frequency band and difficult fabrication.…”