en 5-Antenna Antenna Research Paper Research Paper <span style="font-size:10.0pt"><span style="font-family:&quot;Times New Roman&quot;,serif">This paper proposes a novel wideband circularly polarized L/S feed system for portable satellite communications. The feed system integrates a multi-stage septum polarizer, a sloped waveguide transition, and an axial choke conical horn to ensure uniform reflector illumination of a 3-meter reflector antenna. Unlike existing septum-based feed designs, the proposed structure achieves an ultra-wide 47% fractional bandwidth (1.6&ndash;2.6 GHz) with an axial ratio below 2 dB. It is explicitly optimized for use as a reflector feed rather than as a standalone antenna. A foldable multi-piece strut mechanism is introduced to enhance portability and facilitate field deployment. In addition, a convex plate at the reflector vertex is employed to reduce feed blockage and improve gain, particularly at higher frequencies. Simulation and measurement results are compared, demonstrating superior performance of the proposed antenna to existing solutions, including high isolation (>15 dB) between ports and sidelobe levels better than 26 dB. The combination of wideband circular polarization, reflector-level optimization, and mechanical portability distinguishes this work from prior septum-horn and portable reflector-antenna solutions.</span></span> Satellite communication, circular polarization, septum polarizer, corrugated horn, reflector antenna, wideband antenna, portable ground station. 4083 4083 http://ijeee.iust.ac.ir/browse.php?a_code=A-10-4211-1&slc_lang=en&sid=1 Amir M. Zaker 1800319475328460017993 1800319475328460017993 No Department of Electrical Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran mohammad bod mohammadbod@sru.ac.ir 1800319475328460017992 1800319475328460017992 Yes Department of Electrical Engineering, Shahid Rajaee Teacher Training University, Tehran, Iran Hamid G. Bafghi 1800319475328460017994 1800319475328460017994 No Department of Electrical Engineering, Sharif University of Technology, Tehran, Iran.