Frequency Selective Radome With Wide Diffusive Bands

This letter presents a frequency selective radome that realizes two-sided wideband backscattering reduction by combining two diffusion strategies. The upper layer of the radome is capable of diffusing the incident wave at low frequencies based on copolarized scattering cancellation. A bandpass frequency selective surface integrated with a coding metasurface is adopted as the bottom layer, which acts as a reflecting ground for the upper layer and also diffuses the incident wave at high frequencies by cross-polarized polarization conversion. An equivalent circuit is employed to analyze the frequency-selective radome. A sample with a size of 288 × 288 mm is designed and fabricated for verification. A high transmission window with an insertion loss less than 1 dB in the desired passband from 7.9 to 12.2 GHz and a wide low-backscattering band from 2.3 to 15.6 GHz are achieved simultaneously. Measured and simulated results are in good agreement verifying the validity of the design concept and its effectiveness in reducing backscattering over a wideband.