A Novel Circular TE01-Mode Bend for Ultra-High-Power Applications

Abstract

Future Linear Colliders and Accelerators require rf systems and components that are capable of handling hundreds of megawatts power levels at x-band frequencies and higher. Standard rf components that have been in use for a long time such as waveguide bends, directional couplers and hybrids, can not be used because of peak field considerations. Indeed, one has to reinvent most of these components taking into account the constraints imposed by ultra-high-power operation. Here, we present a new design for circular waveguides bends propagating the low-loss TE₀₁ mode. The bend has smooth walls and low field levels. We present a simple synthesis process for designing such a device. The general philosophy of this technique can be applied to other components as well. We describe the detailed design of the bend and compare our design with finite element simulations and experimental data. The bend has very low ohmic losses, and the TE₀₁ mode is transmitted with virtually perfect mode purity.