Cold-Test Characterization of Metamaterial-Assisted Side Coupled Cavity

In this article, a new S-band metamaterial-assisted side coupled cavity (MSCC) structure is proposed for high-power microwave (HPM) applications. The electromagnetic features of the proposed MSCC and conventional side coupled cavity (SCC) are investigated. The dispersion curve and average interaction impedance of the two models have been compared to ascertain the advantages of MSCC over SCC. For the
$\pi $
/2 mode resonant frequency, the radial dimension of MSCC is 17 mm, whereas the radial dimension of the conventional SCC is 39 mm. The average interaction impedance of the proposed MSCC is
$\sim 200\,\Omega $
, while it is
$\sim 110\,\Omega $
for the SCC. The proposed MSCC offers high average interaction impedance and compact size compared to SCC. The transmission properties of the fabricated MSCC have been measured with the help of Anritsu MS2037C VNA Master. The measured reflection coefficient confirms the operation of MSCC at 2.89 GHz. The measured and simulated values of reflection and transmission coefficients are in good agreement. The proposed structure is designed to be used as a modulation cavity in one of the prominent HPM sources, i.e., Reltron oscillator.