Study on Rectangular Waveguide Grating Slow-Wave Structure with Cosine-Shaped Grooves

Recently, a new need for high-frequency, high-power sources has been emerging for advanced radar and communication needs, with frequencies in the band between 100 and 300 GHz and peak powers as high as several hundreds of kilowatts, and with bandwidth of up to 10%. After investigation of the interaction mechanisms of different slow-wave structures, the rectangular waveguide grating SWS has attracted the scholar´s interest due to some of its peculiarities: the scalability to smaller dimensions and shorter wavelengths, high precession of manufacturing and assembling, super thermal conductivity and low loss, which make it worth consideration, especially at millimeter-wave frequency-band. From the investigation of the different structures, such as V-type, cosine-type, dovetail-type, etc., the cosine-shaped groove SWS has the weakest dispersion and the widest bandwidth. In this paper, this type of structure was analyzed.