A low loss frequency scanning planar array using hybrid coupling

An X-band frequency scanning microstrip array is proposed in this paper. In the structure, an E-plane bent rectangular waveguide is used as slow-wave structure to achieve the low loss. The array is fed by using a combination of aperture coupling from the slotted waveguide and microstrip line feeding. The simulated results show that the range of the scanning angles is (-48°, 45°), the gain is above 21.6dBi at the working bandwidth and the peak gain is 23.2dBi. In addition to low feed loss and wide angle scanning capability in one dimension under limited bandwidth, this proposed design is with compact structure.