A novel hybrid active quasi-circulator for L-band applications

In this contribution a hybrid active quasi-circulator operating in L-Band is presented. E-pHEMT active devices mounted on ceramic substrate with copper metallization have been used. The proposed quasi-circulator is composed by active non-reciprocal phase shifters and classical passive combining structures to get the desired functionality. Insertion losses better than 2.1 dB, isolation higher than 20 dB in the 1.35 ÷ 1.65 GHz frequency band is obtained, while an isolation better than 30 dB over a 15% bandwidth. Port matching is better than 15 dB on coupler´s ports, while the splitter one reaches 10 dB. The overall quasi-circulator exhibits a 22 % operating bandwidth.