Research on microstrip multiway unequal power divider/combiner

In the paper, a type of TEM mode multichannel power divider/combiner and modified design suited for its wide frequency band working are presented. Each branch of it is composed of three-section or six-section quarter-wavelength transmission lines of unequal characteristic impedance values and an isolating resistor. All these branch isolating resistors are in the form of a star connected to a common point. The advantages of the new design are: (i) all the ports satisfy the matching conditions, (ii) the branch output power has arbitrary amplitude ratio and identical transmission phase; each of the branch ports' impedances can take different values, (iii) high isolation at the branch output ports, (iv) suitable for the realisation of the microstrip plane structure. The simple experiment of the three-way divider with the working frequency range of 0.7-1.0 GHz, amplitude ratios being separately -6.5 dB, -4.8 dB and -3.5 dB, proves that the new design is practicable.