Design of Compact Filtenna Based on Capacitor Loaded Square Ring Resonator for Wireless Applications

Abstract

This paper proposes and demonstrates a compact integrated filtering antenna built on a square ring resonator coupled with a capacitors loaded microstrip line filter. A microstrip filter module is connected to feeding line of the conventional patch without adding extra space. Thus, the combined configuration possesses radiating and filtering functions simultaneously. The proposed filtenna has a fractional bandwidth (FBW) of 3% at center frequency 2.4 GHz with 2.5 dB of maximum gain. The obtained result shows that the proposed design shows good stopband gain rejection, good selectivity at band edges, and smooth passband gain. Furthermore, the introduced filtenna has advantages of a small size and a simple structure, which makes it ideal for interconnection with different wearable devices operating within 2.4 GHz wireless system range.

Design of Filter Integrated SPDT Switch Using Capacitor Loaded Ring Resonator with High Isolation

“…Integrating multiple RF components into one single module is an effective approach to minimize circuit size, mismatching loss, and power consumption. Various multifunctional microwave circuits have been successfully demonstrated, including antenna integrated with RF switch [1,2], integrated filter antenna [3][4][5], and even power amplifier integrated with antenna [6].…”

Synthesis approach to design a compact printed monopole filtenna for 2.4 GHz Wi‐Fi application

“…The demand for wireless services have seen exemplary growth, whether it is Wireless Local Area Network (WLAN), Worldwide Interoperatability for Microwave Access (WiMax), Global Positioning System (GPS) or portable devices such as mobile phone, Bluetooth, medical equipments, etc. Antenna and filters being inherent passive components in RF front‐end system of wireless communication, there is exponential surge in research targeting to achieve the desired features like light weight, compact, low cost robust front‐end system with good filtering and radiating properties 1‐18 . The performance of front‐end system deeply affects the efficiency and quality of wireless communication system.…”

“…Conventionally, the reported filtennas follows two design approaches, like fusion method 1‐4 and filter synthesis method 5‐13 , 16,18 . Filtennas based on fusion approach, focused on antenna design.…”

“…To improve the filtering performances, an a quarter wave impedance matching structure, 10,13 was used, which provides good integration between antenna and filter, but it increases overall size of filtenna. The filtenna in References 7,8, utilizes capacitor loaded square ring resonator (CLSRR) and Dumbell‐shaped resonator, respectively, but it limits their operational bandwidth. The filtenna, 9 achieves wideband characteristics but admittance inverters were difficult to synthesize.…”

“…Various reported filtennas 6‐10 finds application in 2.4 GHz application. Inspite of being branded as garbage band and its numerous demerits, 2.4 GHz spectrum is extremely popular for Wi‐Fi enabled devices due to its easy availability, maturity, ability to penetrate through solid objects, better range and low cost of technology that operates in unlicensed band.…”