Antenna Arrays With Simultaneous Main Beam Shaping and SLL Suppression for Intelligent Transportation Systems

Reliable and flexible beam control, featuring precise main beam (MB) shaping and effective sidelobe suppression, is crucial for intelligent transportation systems (ITS) to support diverse communication, accurate sensing, and precise localization requirements in dynamic environments. To address these requirements, this paper presents a novel constrained optimization model for designing antenna arrays capable of generating desired MB radiation patterns with suppressed sidelobe levels (SLLs). By combing the weighting coefficients with field distribution across the MB region, the proposed approach enables flexible MB control while strictly constraining the SLL through maximization of the energy ratio between the MB and sidelobe regions. In order to evaluate the effectiveness of the proposed method, the synthesis of pencil, flat-top and cosecant-squared beams with SLL suppression, is investigated by using a 16-element linear microstrip array and a 6×6 planar microstrip array, and the three desired radiation patterns are realized with SLLs all below –30 dB. Simulation and measurement results confirm that the proposed method exhibits outstanding performance in achieving simultaneous beam shaping and SLL suppression. In contrast to existing beam shaping techniques, the proposed approach offers a closed-form analytical solution, thereby eliminating the need for iterative numerical optimization, providing an efficient and universal solution for flexible radiation pattern synthesis in ITS applications.