I. Introduction
The Wilkinson power divider is a symmetrical device commonly used in microwave engineering to divide the input signal into equiphase and equiamplitude output signals. It provides good port matching and high isolation between the output ports while maintaining a low loss operation [1]. Although the Wilkinson power divider is preferred for monolithic microwave integrated circuits (MMIC) due to its ease of fabrication and planar structure, it is not useful in wideband applications and consumes valuable chip area because of its quarter-wave length arms. In order to address the first issue and improve the bandwidth, multisection hybrids with a number of cascaded transmission line arms and bridging resistors [2] and a modified isolation network with a series RLC circuitry [3], [4] have been proposed. Regarding the second issue to reduce the circuit size, lumped element -network and T-network equivalents of the quarter-wave length arms [5], [6] and capacitive or inductive line loading [7], [8] have been suggested. On the one hand, techniques proposed for wideband operation require more circuit area; on the other hand, modifications suggested on the original divider to reduce its size decrease the bandwidth of operation.