Analysis And Research Of Broadband Series Feed Network Of Waveguide In X Band

In recent years, waveguide device is a popular topic in microwave field as its characteristics of hard structure , low insertion loss , high power-capacity. Rectangular waveguide couplers are applied widely in feed network of radar, measure systems and signal detection because of their special performance.The two factors which affect the performance of series feed network, are coupling of units and their capability. There are many kinds of coupling units, such as rectangular waveguide broad-wall and narrow-wall holes coupling, transverse and vertical slots coupling, cross-aperture coupling. However, as we know, there is no published article about multi-slot couplers. In this thesis the theory of normal couplers are analyzed firstly. The simulation of multi-slot coupler in X-band is done. The full wave analysis method of finite-difference time-domain is used to analyze the effect of the slots parameters to couplers performance. The S parameter of coupler is got and a cross-waveguide multi-slot coupler which has the function of tight coupling, high directivity is designed. Further multi-port network cascaded theory is applied to simulate the cascaded network formed by several couplers to save computer resource and calculation time. And the scattering matrixes of several cascaded networks are got.Calculation results and test data of cross-waveguide multi-slot couplers are in good agreement. And fifteen ports series feed network in this thesis is shown. The method and the results mentioned have been applied to radar feed network. And the parameters we get have good directive function to engineering.