A hybrid rat-race coupler whose dimensions are reduced with the help of artificial lines

For the purpose of miniaturization of the coupler, a variant of artificial transmission lines consisting of LCL elements is proposed. Their use made it possible to achieve a 4.3-fold reduction in the area. The proposed scheme for constructing a coupler was theoretically and experimentally investigated. The results agree with each other. The differences between the traditional and compact scheme are mainly an increase in losses by 0.6 dB and a narrowing of the band by 1.6 times.