Multibeam Antenna for Wide-Angle 96-Beam Coverage at Ka-Band Using a Multifocal Transmit-Array

In this work, the authors present an innovative Ka-band multibeam antenna concept designed to deliver cost-effective, wide-angle coverage for next-generation wireless communication systems operating in 5G and beyond (FR2) frequencies. Addressing the persistent trade-off between antenna compactness, gain performance, and scanning range, the study explores a refined spatially fed transmit-array (TA) architecture optimized for both low focal-to-diameter ratios (F/D) and broad angular coverage.

By employing a multifocal transmit-array fed by a 19×5 WR38 waveguide network operating at F/D = 0.34, the system achieves a 25 dBi gain with scan losses below 3 dB across a zenithal scanning range of −55° to +25°—equivalent to an 80° total coverage and smooth 3 dB beam crossover levels. This configuration demonstrates that a properly optimized TA can overcome traditional design limitations, offering a compact, efficient, and scalable multibeam antenna solution suitable for high-frequency, high-capacity communication systems.

Published in the 18th European Conference on Antennas and Propagation (EuCAP 2024), Glasgow, United Kingdom.