Beamforming at mm-Wave and beyond is expected to be a critical need for many emerging applications such as Internet of Things (IoT), vehicular networking systems, and unmanned aerial navigation systems as well as 5G/6G backhaul communications. A new technique is proposed using quasi-optical beamforming that will address the shortcomings of existing beamforming approaches. These structures are passive (or nearly passive) having low cost, low power consumption, compact size and weight, have bandwidth advantages, and are expected to be able to operate at higher frequencies. The proposed structures give sufficient degrees of freedom to control the beamsteering angles by varying the dielectric constants and geometries of these structures and can form simultaneous multiple low overlapping beams. This approach increases the gain of the radiating source resulting in highly directive beams; our studies suggest that sufficient dielectric and shape parameters are available so that electrical tuning of beamformer parameters is possible. These structures are designed for a 1x3 microstrip patch antenna to demonstrate the formation of three simultaneous low overlapping beams. The effects on bandwidth are negligible upto 4.4%, and scanning angle of 180° has been achieved by using vertically oriented dielectric wedges. 6 dB gain enhancement and the capability to scale to larger 2D arrays have also been demonstrated. Full wave simulation results in Ansys HFSS are provided to demonstrate the proposed techniques, and validation is done in CST MWS.
"Quasi-Optical Beamforming Approach Using Vertically Oriented Dielectric Wedges," Progress In Electromagnetics Research M,
Vol. 105, 67-78, 2021. doi:10.2528/PIERM21072501
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