Mode purity estimation of the gyrotron RF beam

In this paper, the implementation of a phase retrieval algorithm for determining the phase profile of gyrotron output beams from measured intensity patterns at different planes is described along with a novel mode estimation technique based on a surface matching algorithm. A simulated Gaussian beam at different planes is considered as input of the phase retrieval algorithm. The proposed mode estimation technique supports the accurate mode estimation of different linearly polarized modes present in gyrotron output RF beam.