Multi-resonator Variations of 120° Sectoral Microstrip Antennas for Wider Bandwidth Amit A. Deshmukh, Pritish Kamble, Akshay Doshi and A. P. C. Venkata Abstract Sectoral Microstrip Antennas are realized by modifying the circular microstrip antennas. In this paper, proximity-fed design of 120° Sectoral microstrip antenna is discussed first. It yields bandwidth of nearly 650 MHz (*49%) with antenna gain of above 8 dBi in 1200 MHz frequency range. To enhance the bandwidth and gain of 120° Sectoral microstrip antenna, its various gap-coupled configurations coupled along the diagonal axes are proposed. Configurations with either single patch or two patches gap-coupled along diagonal axis are discussed with variations in the coupling edges. A maximum bandwidth of more than 1000 MHz (>70%) is realized for specific configurations of 120° patches, when they were coupled along both diagonal axes. In all gap-coupled variations, broadside MSA gain is nearly 9 dBi with pattern maximum in boresight direction is observed. Keywords Broadband microstrip antenna Á 120° sectoral microstrip antenna Gap-coupled configuration Á Higher broadside gain 1 Introduction Sectoral microstrip antenna (MSA) is a variation of circular MSA (CMSA) and for Sectoral angle in the range of 270°–340°, it gives additional resonating mode, whose frequency lies below the fundamental TM 11 mode frequency of circular patch [1, 2]. Bandwidth (BW) enhancement of Sectoral MSA (S-MSA) with angle in the range of 270°–340° has been obtained by using slot or tuning the Sectoral angle itself [1, 2]. But due to orthogonal resonating modal currents, radiation pattern exhibits higher cross polar content that leads to gain fluctuation in the boresight direction by 3–4 dBi [2]. However, as these antennas provide BW in the A. A. Deshmukh (&) Á P. Kamble Á A. Doshi Á A. P. C. Venkata Department of Electronics and Telecommunication Engineering, SVKM’s, D J Sanghvi College of Engineering, Mumbai, India e-mail: amit.deshmukh@djsce.ac.in © Springer Nature Singapore Pte Ltd. 2018 H. Vasudevan et al. (eds.), Proceedings of International Conference on Wireless Communication, Lecture Notes on Data Engineering and Communications Technologies 19, https://doi.org/10.1007/978-981-10-8339-6_19 169