Traveling wave slot array power combiner at 74 GHz

Power splitters/combiners have been investigated for applications in microwave and millimeter wave frequencies with the use of distributed amplifiers instead of a single high power source. Waveguide power dividers and combiners have been studied in standing wave and traveling wave modes, because of their high efficiencies [R. Bashirullah et al., IEEE Trans. Microwave Theory Tech., July 2000 and X. Jiang et al., IEEE Trans. Microwave Theory Tech., Jan. 2003]. Standing wave power splitters/combiners are efficient but have limited bandwidth. In order to realize reasonable bandwidth in such a system, the array has to be divided into many sub-arrays, thereby resulting in a complicated feed network. Traveling wave arrays provide a greater return loss bandwidth with a small sacrifice in efficiency because of the power dissipated in the load. Traveling wave antenna arrays suffer from beam squint with frequency. In power splitters/combiners, there is no such limitation.