Dual‐band branch‐line coupler with shorted stepped‐impedance stubs arranged in a Π‐shaped topology

Abstract

This article presents a transmission‐line‐based 3‐dB dual‐band branch‐line coupler. The coupler is easily realizable for ratios between the upper and lower operating frequencies ranging from 1.270 to 2.628. This means that it can be designed for two operation frequencies that are closer to each other in comparison with existing simple circuit topologies based on transmission lines, when considering a compact design. The complete set of equations for all possible responses of this dual‐band 90° hybrid coupler is derived. To evaluate its practical feasibility, the proposed circuit is analyzed with respect to the characteristic impedances of its transmission lines. A step‐by‐step procedure is presented to help the circuit designer deal with the use of the equations and all their degrees of freedom. For experimental validation, a microstrip dual‐band branch‐line coupler has been designed for operation at 3.835 and 5.285 GHz. A good agreement is observed between simulated and measured results.

Design of branch line directional coupler for 5G millimeter wave communication

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Phase shift switching of a miniaturized ultra‐wideband hybrid coupler for 5G technology

“…These bidirectional structures can provide equal power split between two outputs (coupled and through ports) with a well-defined phase shift difference, while the fourth port is strictly isolated. [3][4][5][6][7][8][9] In the state of the art, there are two types of popular hybrid couplers, the first one, in which the phase shift between the two output signals is 90 and a power split of 3 dB. In the second one, the phase shift between the two output signals is 180 and a power split of 3 dB.…”

“…Hybrid couplers are the single integral components employed in several microwave integrated circuits that can be used as power dividers, combiners, and frequency duplexers. These bidirectional structures can provide equal power split between two outputs (coupled and through ports) with a well‐defined phase shift difference, while the fourth port is strictly isolated 3‐9 …”