Wideband Microstrip 90° Hybrid Coupler Using High Pass Network

Table 1

Performance comparison of the previously reported branch-line coupler.

	Impedance bandwidth	Relative bandwidth with ±5 dB magnitude imbalance	Relative bandwidth with ±5° phase imbalance	Circuit size reduction
[1]	100%	75%	70%	Nil
[2]	70%	60%	56%	Nil
[3]	82%	75%	65%	52%
[4]	57%	63%	46%	65.4%
2-section branch-line coupler	50%	75%	50%	Nil
This work	90%	94%	88%	45%