Method for determining the modes existing in a waveguide, and an arrangement for carrying out the method

摘要

The invention relates to a method for determining the modes of electromagnetic fields in a waveguide and their power component, by measuring in the remote field of the open waveguide, and an arrangement for carrying out the method. In order to identify the superimposition of modes in oversize cylindrical waveguides, the methods used until now were as follows: reflection method, mode coupler and field imaging. According to the invention, the complex amplitudes of the electrical field components E PHI and E theta of the image of the modes are measured and evaluated by means of four receiving sensors (3a, 3b, 3c, 3d) on an orthogonal measurement plane (x-y) which is located in the remote field of the waveguide (1). The advantages achieved using the invention are, in particular, that the complete mode spectrum and the power components of the individual modes within the total power can be determined. <IMAGE>