Miniaturized Hybrid Rat-Race Coupler of a 2.5 GHz Loaded by Resistors

A rat-race coupler is one of the essential components used in microwave circuits. Rat-race coupler has numerous applications in satellite communication, phased array radar antenna systems and radar. Recently, wireless communication systems usually require smaller device size, in order to meet circuit miniaturization. Thus, size reduction becoming major design considerations for practical applications. This paper includes design the proposed microstrip rat-race coupler for frequency 2.5 GHz. The area of the proposed rat-race coupler compared with the conventional structure, the proposed rat-race coupler in this paper has smaller size than the conventional structure. The main outcome of this work is reducing the area of the proposed coupler by 10%. Microwave Office (MWO-225SUF) tool is used to execute the design of the coupler in this work.