Wideband Miniaturized Multi-Port Correlator for 5G Applications at 28 GHz

In this paper, a novel symmetric multi-port correlator using 90 ^o circular hybrid couplers is proposed at the center frequency of 28 GHz. The work is focused on designing the multi-port circuit on a low thickness and low dielectric constant substrate (Rogers RT/Duroid 5880). The circuit is suited to realize a low-cost architecture and integrate with antennas for mm-wave applications. Due to the structure, this design can be implemented without any additional off-chip components. Moreover, the octagonal structure minimized the overall size of the circuit while providing enough space to solder 8 connectors. The performance of the designed structure is assessed via full-wave computer simulation technology (CST) and Advanced Design System (ADS). As simulation results show the proposed compact size multi-port network has a good fractional bandwidth of 28.6% from 24 to 32 GHz and superb phase resolution at four output ports.