The Study On Flexible Antenna With Dual Notchedband Characteristic

With the development of wireless communication technology, narrowband communication mode isnot the only choice for communication. Ultra-wideband (UWB) technology has attracted a large number ofattentions for its anti-interference ability, high positioning accuracy, and low system complexity. As a corecomponent in the communication device, antenna has a great influence on the size of wireless equipment.To improve performance and portability of the communication equipment, a flexible UWB antenna withnotched band characteristic was presented in this paper. By using the software and experiment results, theproposed antenna has a good performance on wireless communication. The influence of bend has also beendiscussed and the detail will be seen as follows:(1) In order to improve the portability of the proposed antenna, a flexible substrate which callspolyimide is in use. Compared with the traditional PCB substrate, polyimide has a bendable characteristic,thinner in thickness and a lighter weight, which can reduce the occupied space in the communicationdevice.(2) The operating frequency band of Ultra-wideband is from3.1GHz to10.6GHz, which coversWIMAX (3.3GHz-3.7GHz) and WLAN (5.15GHz-5.825GHz). And a fewer flexible ultra-widebandantenna has one notched band while most of them even doesn’t has notched-band feature. What’s more, itis likely to cause signal interference. In order to avoid the interference signal, a flexible ultra-widebandantenna with dual-notch characteristic is presented, which has a stop band on both WIMAX and WLANfrequencies.(3) Stub and slot are two common structures to produce the stop band. In this paper, the proposedantenna used both methods to achieve the dual-notched band feature while most of the UWB antenna onlyused one. As a flexible antenna, the degree of bending of the antenna is also discussed. With CSTMICROWAVE STUDIO, the surface current on the antenna is analyzed and combining with the measuredresults, the proposed antenna can meet the standard of UWB communication.