Design of novel compact filtering power divider with high selectivity and wide stopband

In this paper, a dual-functional device with power divider and filtering is designed with high selectivity and wide stopband in a compact size. A filter is used to replace the quarter-wavelength line of the traditional power divider. The filter consists of two half-wavelength resonators with same fundamental frequency and different harmonics. Thus, the out-of-band rejection is enhanced. To verify the proposed idea, a filtering power divider with the operating frequencies of 2.4 GHz (f
0
) is designed. Good power division and bandpass responses are obtained. The total size of the circuit is 0.21⋋
g
× 0.33⋋
g
, the stopband can extend to 3.9f
0
under −20 dB, where ⋋
g
is the guided wavelength of 2.4 GHz.