Radio Frequency Power Division Filter Network Synthesis Method And Its Application

With the continuous advance of communication systems in recent years,the design requirements for RF front-end systems have become more and more stringent.As a multi-functional device with filtering and power division at the same time,the filtering power divider(FPD)has the advantages of miniaturization,low cost and high integration,and has received extensive attention in recent years.The synthesis method for FPD network is an important theoretical basis for the circuits design.It can not only concisely reflect the topological structure,but also accurately predict the network response.However,the current power division filter network synthesis method is still mainly through the indirect conversion on the basis of the traditional two-port filter network synthesis,which cannot effectively solve the problem of synthesis for the feature integrated and mixed topology FPD network,which seriously restricts the highperformance and miniaturized FPD synthesis and design.In this dissertation,the newly defined multi-functional integrated FPD synthesis technology,the advanced theory of generating and controlling transmission zero flexibly,and its application schemes are explored based on the traditional coupling matrix synthesis theory.The main work and contribution of this dissertation are included as follow:1.A new type of FPD synthesis method with multi-feature integrated such as phase shift and impedance matching is established.Based on the generalized FPD network characteristic scattering polynomial,an additional ideal phase shift is introduced,and derived to the admittance parameter under arbitrary terminal impedance.On the other hand,by introducing non-resonating nodes at the source and load terminals,the ideal phase response can be obtained,and the corresponding admittance parameters are given through the circuit analysis of the multi-port FPD low-pass prototype.Then,combining the admittance parameters of the two to obtain the calculation formula of the coupling coefficient,the coupling matrix extraction of the feature integrated FPD is realized.2.A new type of mixed topology of FPD synthesis method is presented.Combining the mixed design of the cross-coupling and the pole extraction unit,it can effectively compensate for the defects that the cross-coupling structure is difficult to tune and the pole extraction unit can only generalize pure imaginary transmission zeros,improving the overall performance of the FPD network.Then,the improved quantum particle swarm algorithm(QPSO)is used to approximate the minimum value of the objective value function,and the coupling matrix of the arbitrary mixed topology FPD network is extracted to improve the overall efficiency and design flexibility.3.Take the above-mentioned new FPD synthesis method as the theoretical guide,and combine the script file of the graphical user interface(GUI)to complete the design of the FPD synthesis software.In addition,using the coupling elements information given by the synthesis method,combined with the denormalization calculation formula,determine the structure and size of the physical circuit,realize the modeling simulation and processing test of the circuits,and complete the prototype design of the FPD in the industrial application frequency,which Verifying the significance of the proposed synthesis method for guiding the application of engineering design.The study of synthesis method of FPD in this thesis simplifies the design process of the FPD,improves the flexibility of topology selection,modeling,simulation,and optimization time,which reveals potentially practical applications in engineering.