Broadband cavity-backed slot antenna array with 45° slant polarization

The radiation characteristics of a cavity-backed four-slot antenna array are investigated in this paper. By employing cavity-backed slots antenna element, the antenna array has wide bandwidth and wide beam width. The feeding network of the antenna array mainly consists of shielded microstrip line. Both simulated and measured results of the antenna return loss and radiation patterns are presented. The measured VSWR<;2 bandwidth is 55% of the center frequency 21.8GHz. It is shown that using shielded microstrip line leads to better radiation performances. Besides, good agreement can be observed between the measured radiation patterns and the simulated values. These findings may provide useful insights and guidelines for the design of 45° slant linear polarization wideband antenna array in K-band with wide beam.