A new type of high efficiency Gaussian beam launcher

The corrugated pyramidal square horn with corrugations in the E-plane walls is investigated by means of Gaussian-Hermite beam mode analysis. The fractional power in the fundamental beam mode is about 98%. The near- and far-field radiation patterns are calculated by Gaussian-Hermite beam mode analysis. The latter is compared with the result obtained by conventional aperture field integration method, and good agreement is found. Finally, the accuracy of Gaussian beam mode analysis is discussed. The high fractional power in the fundamental beam mode of the horn indicates that it can be used as a high efficiency Gaussian beam launcher in quasi-optical systems.