A Planar Wide-Angle Scanning Phased Array With X-, Ku-, and K-Band RCS Reduction

This communication presents an artificial magnetic conductor (AMC) structure-loaded phased array with broadband low-RCS and wide-angle scanning performance. A substrate integrated with the cavitybacked antenna with wide beamwidth and decoupling cavity is used as the basic array element to increase the field-of-view scanning range of arrays. Meanwhile, a checkerboard-shaped AMC structure with a broadband region of 180 degrees (+/- 37 degrees) phase difference is designed and loaded around the array to reduce its RCS in and out of the band. This communication is validated through measurements that matched well with simulations. The proposed array operates at 10.8 GHz and provides a wide scanning region from -70 degrees to +70 degrees in the H-plane with particularly small gain fluctuation (+/- 1.5 dB). Moreover, the backscattering of the proposed array can be reduced to -6 dB for both TE and TM polarizations, covering the X-, Ku-, and K-bands. The proposed approach has the potential application in smart skin designs due to its low profile, powerful scanning ability, and broadband RCS reduction.