Simulation and Experimental Investigation on W-Band Suspended Ridged Loaded Microstrip Meander Line Slow Wave Structure

To improve the coupling impedance of the traditional suspended microstrip meander line (S-MML) slow wave structure (SWS), this article proposes the suspended ridged loaded microstrip meander line (SR-MML) SWS and conducts a comparative analysis of their performance. The high-frequency, transmission, and beam-wave interaction characteristics are investigated using CST software. Driven by the same input signal and electron beam, the SR-MML traveling wave tube (TWT) demonstrates higher output power, gain, and electronic efficiency than S-MML at 95 GHz. Furthermore, the SR-MML SWS, with a width of 35
$\mu $
m and a thickness of 3
$\mu $
m, can be fabricated on a quartz medium using lithography technology. The test of the assembled SR-MML circuit revealed an S
$_{11}$
of less than
$-$
12 dB across the 90–100 GHz range, and a transmission parameter S
$_{21}$
greater than
$-$
8 dB.