Compact dual-band power divider with highly selective bandpass response

A compact and high selectivity microstrip dual-band power divider (PD) with Chebyshev bandpass response is proposed in this paper. By using the coupled-resonator technique, both the size reduction and filtering characteristic can be achieved. The dual-band response is realized by introducing multiple coupling routes between input and output ports. Moreover, the two passbands can be well controlled by varying the coupling strengths between adjacent resonators. Thus, greater design flexibility for the dual-band filtering PD can be obtained. For demonstration, a dual-band 4th-order Chebyshev filtering PD with a compact size of 0.47λ
_g
by 0.21λ
_g
has been designed and fabricated. Furthermore, a good output isolation of greater than 25 dB is achieved.