In this article, a combination of microstrip bandpass filter and antenna is presented to give sharp response at desired frequency bands along with very low insertion loss. Three single bandpass filters, designed at wireless local area network (WLAN) and worldwide interoperability for microwave access (WiMAX) frequency bands, are integrated into a tri‐band bandpass filter. An ultrawideband antenna is further added to the structure. The antenna operates in 2.23–2.587, 3.468–3.816, and 5.345–5.607 GHz, suitable for WLAN 2.4 GHz and WiMAX 3.5/5.5 GHz applications. The proposed tri‐band filtering antenna shows monopole‐like radiation patterns in the desired frequency bands with high out‐of‐band rejection. Good agreement between simulated and measured results validates possible applications. © 2015 Wiley Periodicals, Inc. Microwave Opt Technol Lett 57:233–237, 2015

No abstract

The aim of this paper is to present different ways to extract electrical models of an antenna specifically designed for Radio Frequency IDentification (RFID) Ultra High Frequency (UHF) communications. More precisely the models are extracted from a helical dipole designed to operate in the European RFID band and in the context of smart textiles. This kind of antenna was chosen because its electrical properties and radiation pattern are relatively robust with respect of stretching deformation. After presenting the antenna's design, two strategies to extract antenna models are discussed and then compared. The first method is taking into account the antenna's physical dimensions and shape, and the second one, which is a general method relevant to any other antenna geometry, is based on the rational approximation of the antenna's frequency response.

A single-port compact planar integrated ultra-wideband (UWB)/frequency-reconfigurable narrowband monopole antenna is proposed. Reconfigurability is achieved by inserting a varactor-diode tuned bandpass filter into the feed line of the UWB antenna. The antenna operation is changed from wideband to narrowband by activating PIN diode switches in the structure. Good tunability obtained within a wide sensing band of 2.2À6 GHz is significant for cognitive radio applications.