Design of a fully integrated wideband six-port network on a single layer microstrip substrate

The design of a novel wideband six-port network on a single layer microstrip substrate is presented.Two different configurations of the single-layer six-port networks, one conventional and the other nonconventional, are designed, fabricated, and measured. The six-port network based on the conventional configuration is formed by one Wilkinson divider and three couplers, with one unused port terminated with a coaxial match termination. The nonconventional six-port network, proposed here, is constructed using a similar configuration except one of the couplers is replaced by a quadrature power divider eliminating the need for match termination. To obtain fully planar device with wideband operation, the six-port networks use double-stage Wilkinson dividers, disk type couplers, and a wireless via 90° phase shifter. Their performances are assessed via full-wave electromagnetic simulations and measurements. Both the simulated and the measured results show a wide bandwidth of the two six-port configurations in terms of amplitude and phase characteristics across the frequency band of 4.5–8.5 GHz