A method for dividing ratio equalization of power dividing/combining circuits used in a power amplifier

Most power amplifiers with several FETs in parallel utilize a two-way power dividing/combining circuit of asymmetric structure. The asymmetric structure provides unequal power dividing/combining characteristics. In this paper the power dividing/combining ratio as a function of the structure is calculated by using the method of moments and is verified by experiments. The relation between unequal power dividing/combining characteristics and the equal phase plane of current flow is also shown. Finally, a method of equalizing the power dividing/combining ratio by making branch line impedances unequal is presented. © 1999 Scripta Technica, Electron Comm Jpn Pt 2, 82(7): 16–22, 1999