In this paper a miniaturized branch-line coupler is proposed. The topology of the circuit is designed using novel design of T-model approach with open stubs with high-low impedances, which provides necessary bandwidth for WLAN band at 2.45GHz. The miniaturized branch-line coupler is designed and fabricated with a low-cost FR4 substrate as a platform in producing significantly reduction by more than 64.21% compared to the conventional coupler on inexpensive board. Furthermore, the coupler can equally divide the input signal with 90° phase of difference while maintaining the initial power from the source.
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