Design of a 10 GHz TE01–TE11 mode converter using new structure coaxial–parallel method

In a cyclotron system, the output mode is typically the TE0n mode. However, this mode cannot be transmitted over long distances and energy is easily dissipated. It is usually converted to Gaussian mode HE11 through mode conversion for long-distance transmission and application. For circular waveguide TE01-TE11 mode converters, the usual method is to use trigonometric function curves or iterative methods, but these two methods cannot effectively ensure that the input and output are on the same horizontal line. In some specific circumstances, the effectiveness of using these methods will be restricted. The coaxial-parallel mode converter can be effectively designed by researching a new B-spline curve method. Combined with coupled wave equation theory and B-spline curve theory, a working frequency of 10 GHz can be obtained through program design and calculation. For a mode converter with a waveguide radius of 25 mm, the simulation calculation has a conversion efficiency of 99.485%, with the input and output strictly aligned along the same horizontal line.