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.