Analysis on Bilateral Metal-Grating With Different Groove Depth for Cerenkov Amplifier

The dispersion equation of nonstaggered bilateral metal-grating periodic slow-wave structure inside a parallel plate is derived. Under the condition that the groove widths of the upper and lower sides are equal with each other, R_n has been replaced by R, where R_n is the reflection coefficient of the nth harmonic wave. The validity of this process on Rn has been proved by rigorous derivation. Using the iterative technique, the dispersion relation of the bilateral grating structure in asymmetric structure is solved. The numerical results show that the second higher mode of this structure is more suitable for the beam-wave interaction and by adjusting the degree of asymmetry, some high-frequency performances of this mode can be effectively improved.