Research Of High Power Microwave Mode Recognition Based On Far Radiation Field

In high power microwave producer, the microwave tube often has used the over-mode waveguide in order to enhance the power capacity and the efficiency. The high-current electron beam in the over-mode waveguide had driven the many kinds of microwave modes, it is very significant to study the high power microwave by measuring the microwave mode. According to the actual need, the paper has researched the high power microwave mode recognition methods.First, elaborate the circular wave guide and the caliber field radiation theory. Based on the orthogonal characteristic of waveguide mode, the orthogonal principle of the mode plane wave spectrum of open-end waveguide has been deduced in this paper. Making use of this orthogonal characteristic, elaborate a theoretical method to determine the mode contents of over-mode waveguide by means of calculating the integration which integrated function is the inner product of the plane wave spectrum (PWS) of any give mode and the one of open-end waveguide with over-mode. When considered the far field test, the sample plane cannot do infinitely great, the paper has analyzed the truncation error, and proposed the error correction method.Then, explain the basic theory of genetic algorithms. The genetic algorithms are one kind the search optimal solution biological modeling algorithm which devises based on the biological evolution principle.The main characteristic is the colony search strategy ant the individual information exchange in colony, the search does not rely on the gradient information. Especially, it is suitable for processing the complex and the non-linear problem which tradition search method can't solve. The genetic algorithms are used for high power microwave model inversion recognition, at the same time, the paper analyze the sufficiency function and the controlled variable.Finally, establish the simulation model of the test installation, carry on the numeric simulation experiments by using above two methods, the experimental results have indicated that the two methods can accurately determine the mode distribution in over-mode waveguide.