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 similar to 11.2 GHz (X-band) and 21 similar to 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.