A novel feeding network is investigated both theoretically and experimentally. The proposed system with combination of a Wilkinson power divider and two branch-Line couplers is established. The output signals of the system have the same amplitude and 900 phase difference with each other. The size reduction technique is applied to minimize the physical size of the proposed network. In this technique, the ground of the structure is defected, and distributed capacitors and inductors are added to empty space of the branch-line couplers. Moreover, meandered lines are used in order to match the output impedance of the Wilkinson power divider arms and reduce its size. The initial design realized in 2.5 GHz shows the fractional bandwidth of 24%. Then a miniaturized structure is fabricated with 42% smaller size than the main structure while it shows similar electrical performance. For both cases, measurement and simulation results are in good agreement with each other.
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