Ultra‐miniaturised C ‐band power divider using capacitive loading and defect grounded structures

Abstract

This article reports a compact Power Divider design employing a combination of a capacitive load and Defect Grounded Structures (DGS) on GaAs substrate for MMIC technology in the C band. The integration of these two techniques offers a compact power divider with a decrease in quarter-wave transmission line length from λ/4 to λ/16 and harmonic suppression up to 50 GHz. Capacitive loading reduces the size, and DGS improves harmonic suppression and further decreases the size of the structure. The designed power divider is simulated in Ansys HFSS 19.2 and provides a return loss of 25.66 dB, with an insertion loss of 3.01 dB at 5.4 GHz and isolation of 13.37 dB. Isolation is further improved to 30.89 dB using a parallel combination of resistor and capacitor in the isolation network. The prototype of the proposed circuit has been fabricated using RT/duroid® 5880 as substrate. Measurement results show insertion loss and return loss of 3.02 and 23.46 dB. Isolation of 22.43 dB was achieved. The proposed design provides a size reduction of 73.7% with harmonic suppression up to 10th harmonics by 10 dB, making it suitable for high-performance monolithic microwave integrated circuits (MMIC).