A novel power divider with ultra-wideband harmonics suppression based on double-sided parallel spoof surface plasmon polaritons transmission line

A novel wideband power divider with ultra-wideband suppression of harmonics is proposed in this paper. The power divider is composed of double-sided parallel spoof surface plasmon polaritons transmission line (DSP-SSPP-TL) with periodical grooved bow-tie cells. The cut-off frequency of DSP-SSPP-TL can be flexibly adjusted by changing the parameters of bow-tie cells. To demonstrate that, dispersion relations of the bow-tie cells with different parameters are simulated, and three DSP-SSPP-TL counterparts are experimented. Then, a power divider centered at 3.31 GHz (f(0)) is designed, fabricated, and measured. Experimental results indicate that the 10-dB return loss bandwidth of the proposed power divider is about 146% from 0.9 to 5.73 GHz, and the upper stopband is extended up to 40 GHz (12.1 f(0)) with the suppression level above 32 dB. Moreover, ultra-wideband isolation between two output ports of the proposed power divider could be achieved by employing two lumped resistors between two DSP-SSPP-TLs.