An efficient method of designing dual- and wide-band power dividers with arbitrary power division
Capability of microstrip nonuniform transmission lines (MNTLs) for construction of dual-band and broadband unequal Wilkinson power dividers with arbitrary-way, arbitrary frequency band operations, and arbitrary power divisions is evaluated. Also, the MNTL transformers are introduced for dual-band/broadband matching of the unequal output impedances of the MNTL power divider with arbitrary output terminal impedances. The strip width of MNTLs is considered variable and is written as a truncated Fourier series expansion. To show the validity of the design procedure, three experimental MNTL Wilkinson power dividers, which are dual-band two- and three-way power dividers with different power divisions working at 1 and 3.4 GHz and one broadband equal power divider working from 0.4 to 1.8 GHz, have been designed and fabricated. In the first ones with power division of 1.5, outputs isolation and ports matching of less than ?30 dB are achieved. Next, an extended recombinant structure is presented for achieving three-way MNTL power dividers with dual-band operation. The measured isolation between outputs and ports matching are better than 30 dB and measured forward transmissions are between ?4.87 and ?5.45 in two passbands of the divider. Also, for the proposed broadband divider, the measured isolation between the outputs is better than 13 dB in 127% desired bandwidth.  2012 Wiley Periodicals, Inc. Int J RF and Microwave CAE, 2013.
power divider arbitrary power division microstrip nonuniform transmission line dual-band