A Compact CPW-fed Planar Ultra-wideband Antenna with a Frequency Notch Characteristic

A compact and simple design of a CPW-fed planar antenna for ultra-wideband application with a band-notch characteristic is presented. The proposed antenna consists of a rectangular metal patch on a printed circuit board fed by a 50-Omega coplanar waveguide (CPW). By cutting a C-shaped slot in the rectangular radiating patch, a frequency band notch will be created. The proposed antenna yields an impedance bandwidth of 3.1-10.6 GHz with VSWR<2, except the bandwidth of 5-6 GHz for WLAN. The bandwidth and central frequency of the notched band can be adjusted with ease by proper selection of C-shaped slot parameters simulated by the electromagnetic software Ansoft HFSS 10. The antenna is successfully simulated, designed, and measured showing broadband matched impedance, stable gain and radiation patterns.

I. Introduction

Since the Federal Communications Commission (FCC)'s allocation of the frequency band 3.1–10.6GHz for commercial use [1], the feasible design and implementation of ultra-wideband (UWB) system has become a highly competitive topic in both academy and industry communities of telecommunications. In particular, the antenna of ultra-wide bandwidth is the key component of the UWB system and has attracted significant research power in the recent years [2]. Challenges of the feasible UWB antenna design include the ultra-wideband performances of the impedance matching and radiation stability, the constant gain, the compact appearance of the antenna size, and the low manufacturing cost for consumer electronics applications [3].