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This letter introduces a new 90 branch-line coupler with reconfigurable output power ratios (90 BC-ROPR). Unlike a conventional branch-line coupler structure, each arm of the proposed 90 BCROPR is defined by an asymmetrically coupled-line, and its characteristic impedance depends on the configuration of the coupled-line. The main problem that challenged this structure was unwanted loop resonance from the inner transmission lines which form a loop in a disconnected configuration. The proposed structure was designed to obtain 1:1 and 4:1 output power ratios at 3 GHz