Mountain-Shaped Coupler for Ultra Wideband Applications

This paper demonstrates a novel mountain-shaped design for a compact 3-dB coupler operating at ultra-wideband (UWB) frequencies from 3.1GHz to 10.6 GHz. The proposed design was accomplished using multilayer technology in which the structure is formed by three layers of conductors interleaved by a layer of substrate between each conductor layer. Simulation was carried out using CST Microwave Studio; the result was then compared with results from rectangular and star-shaped couplers that implemented the same technique. The results obtained show that the proposed new coupler has better performance compared to both rectangular and star-shaped coupler designs in terms of return loss, isolation, and phase difference. The coupler was fabricated and measured; the measurement results satisfactorily agree with the simulation results

A dual-band array antenna using dome-shaped radiating patches

A novel design of a dual-band array antenna for Wireless Local Area Network and Worldwide Interoperability for Microwave Access applications is presented in this article. The antenna operates at 3.5 dBi (the lower band) and 5.8 GHz (the upper band), with gains of 7.8 and 5.5 dBi, respectively. The corresponding percentage bandwidths are 2.85 and 2.40%. The overall length of the feeding network was reduced significantly because the elements in the array are closer to each other, with a separation of less than keff /4. There is good agreement between simulation and measurement results. The results of the surface current study also are presented

Improved design of tapering and through element series antenna

In this paper, an array of series fed antenna based on tapering patch width and through element is presented. The antenna has wide impedance bandwidth of 16.18% covering from 5.34 GHz to 6.28 GHz with a gain of 6.53 dBi. The use of through element technique reduces the overall length of array structure by 25.47%. It also has lower side lobe level, and wider impedance bandwidth compared to the past research