Circularly Polarized Microstrip-Line-Fed Antenna with Rotated Elliptical Slot Serving Satellite Communications

Abstract

In this article, a simple and compact microstrip-line-fed antenna integrated with rotated elliptical slot with circular polarization is proposed for satellite communication systems. The size and rotation of the elliptical slot is so chosen that it not only provides a large impedance bandwidth but also a large axial-ratio bandwidth (ARBW). The rotation of the elliptical slot around its center is responsible for circular polarization operation and gives an ARBW of 34.39% (8.78–12.15 GHz) which is highest among all earlier reported microstrip-line-fed slot structures intently designed for satellite communications. A large impedance bandwidth of more than 120.57% (8.59 to >20 GHz) is also obtained which covers X-band partially, $$\hbox {K}_u$$-band completely and extends up to K-band. Theoretical and parametric analysis is performed using accurate design equations for the dimensions and rotation of the elliptical slot and feeding distance. The peak gain of 5.45 dB and 3.6 dB is obtained within impedance bandwidth and ARBW range respectively. A good agreement between simulated results and experimental results makes the proposed antenna a very promising candidate for practical $${X}/{K_{u}}/{\mathrm{K}}$$ band satellite communications.