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Ozeki, Gain control in L-band EDFAs by monitoring backward traveling C-band ASE, IEEE Photon Tech- nol Lett 12 (2000), 983–985. V C 2017 Wiley Periodicals, Inc. DESIGN AND DEVELOPMENT OF WIDEBAND RDRA FED WITH PARALLEL CONDUCTING STRIPS CHAMFERED AT EDGES SEPARATED BY PARTIAL MATCHING SLAB Parikshit Vasisht and N. Chattoraj ECE Department, Birla Institute of Technology, Ranchi, India; Corresponding author: vasishtparikshit@gmail.com Received 3 August 2016 ABSTRACT: In this article, a compact wideband rectangular dielectric antenna fed using parallel standing strips chamfered at the edges with partial dielectric matching slab is proposed for upper C-band and X- band applications. Inclusion of the external conducting strip helps in reducing the size of the DRA, facilitates greater ease of fabrication, and helps in shifting the resonant frequency without varying the size of the DRA. Also chamfering the edges of the conducting strips eradicates the discontinuities in the reactance and thus enhances the bandwidth by 10– 12%. Two DRAs with dimensions 4.8 mm 3 9.6 mm 3 10.6 mm were fabricated. The designed antenna has the broad bandwidth ranging from 6.5 to 13.1 GHz. The proposed antenna has the return loss of 245 dB at 7.0 GHz and the impedance bandwidth up to 75% is achieved. The low value of VSWR suggests that the antenna is broadly lossless. More- over, a comparison with the DRA fed without the partial conducting strip shows that the size of the DRA is reduced considerably around 25%. A parametric study of the variation with external partial conduct- ing strip and internal conducting strip is also carried out. The measured results and the simulated results of the proposed RDRA (Rectangular Dielectric Resonator Antenna) match considerably well with each other. The proposed antenna has an omni-directional broadband pattern hav- ing the gain of 6.0 dBi. V C 2017 Wiley Periodicals, Inc. Microwave Opt Technol Lett 59:695–698, 2017; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.30375 Key words: rectangular dielectric resonator antennas(RDRA); higher order modes; wideband; chamfered 1. INTRODUCTION The increase in the demand for wideband application antennas has led to the development of dielectric resonator antennas [1]. They are also known as open dielectric resonators and offer merits like greater design flexibility, ease of fabrication, low conductor loss, high efficiency, wide bandwidth, and compact size [2–4]. They are available in different shapes such as Figure 1 Geometrical configuration of the proposed RDRA with chamfered external conducting strip. [Color figure can be viewed at wileyonlinelibrary.com] DOI 10.1002/mop MICROWAVE AND OPTICAL TECHNOLOGY LETTERS / Vol. 59, No. 3, March 2017 695