Nonradiating Arbitrary Dual-Band Equal and Unequal 1: 4 Series Power Dividers Based on CRLH-TL Structures

A dual-band equal 1 : 4 series power divider (SPD) and an unequal one with a power dividing ratio of 1 : 2 : 2 : 1 are presented in this paper. These dividers are based on the composite right-and left-handed transmission lines (TLs) that are used to replace the conventional TLs in the conventional series dividers in order to achieve dual-band operation. The proposed dividers were designed, fabricated, and measured at two arbitrary design frequencies: 0.915 and 2.440 GHz. Good agreement is achieved between the simulated and measured results. The experimental results show that both the equal and unequal dividers provide in-phase signals at the output ports. Also, the proposed dividers are scalable in size and present the capability of spacing the output ports arbitrarily apart. To the authors' knowledge, these are the first equal and unequal 1 : 4 SPDs with in-phase signals to each of the output ports. The concept of this paper can be easily extended to any number of output ports with arbitrary frequency and power dividing ratio.