Design and Implementation of a Dual-Band Single Layer Reflectarray in X and K Bands

Design and implementation of a dual-band single layer microstrip reflectarray are presented in this communication. The proposed reflectarray operates in two separated broad frequency-bands within X and K bands. Each element in the reflectarray consists of a circular patch with slots, and two phase delay lines attached to the patch. The required phase shifts in X and K bands are obtained by varying the lengths of the phase delay lines. The proposed element has more than 500 and 800 degrees linear phase range within 9.2 ~ 11.2 GHz (X-band) and 21 ~ 23 GHz (K-band), respectively. Measurement results show the maximum gain of 26.2 dB at 10.2 GHz with 16% 1-dB gain bandwidth and 29.7 dB at 22 GHz with 9.1% 1-dB gain bandwidth. With proper arrangement of the elements in the array, the cross-polarization is reduced. The measured efficiency is 47% at 10.2 GHz and 25% at 22 GHz.