A Ka-Band Single-Layer Optically Transparent Transmitarray With Diffusive Radiation for Alignment-Free Indoor Multipoint Communication

This letter presents a glass-based uniform multi-beam transparent transmitarray (UMTTA) that achieves a highly diffusive and uniform radiation pattern over a wide angular range, and supports dual-polarization to enable simultaneous multi-directional coverage for multi-user mmWave communication. This approach alleviates the challenges related to the extremely stringent alignment requirements of conventional transmitarrays (TAs), which feature a single static antenna beam. Leveraging a single-layer, via-less, mesh-grid Minkowski patch unit cell, the design maintains high optical transparency (OT) while providing a phase range for 1-bit quantized operation. Also, a modified parabolic phase with an optimized integer parameter ensures uniform beam diffusion and alignment-free transmitter (Tx)–receiver (Rx) communication. Measurements on a fabricated prototype confirm that high uniformity in wireless coverage is maintained at Ka-band.