| With the increasingly rapid development of modern electronic communicationtechnology, the spectrum resource which can be utilized is more and more limited. Thusthe microwave filter should have better performances, and should be smaller, lighter andcheaper as well. The cross coupling microwave filter is the best choice to meet theserequirements. There exists more than one path between input and output ports, and therealso exists mutual coupling between the paths. Because the transmission zeros can beachieved on the right half of complex plane, and the entire microwave filter phasecharacters can be improved by adjusting the position of transmission zeros.Compared to the traditional microwave filters, cross-coupled filter has morecomplex theories, and it is more difficult to design, so it is necessary to introducecomputer-aided design in the design process to shorten the design cycle and reducedesign costs, facilitate the final adjustment.The main task of this paper is to explore how effective to use computer-aideddesign to complete design and optimization of the microwave cross-coupled filter. Inthis paper, we first discussed several filter function, and focused on the basic theory ofgeneralized Chebyshev function. Later, we presented the working principle of severalelectromagnetic simulation software, such as HFSS, CST, Ansoft Designer. Secondly,we illuminated the synthesis theories and techniques of microwave cross-coupling filter,and focused on how to extract the coupling coefficients and external quality factor, theoptimization techniques of coupling matrix is also discussed. Finally, we detailedintroduced how to use Ansoft Designer to complete the design and optimization ofschematic, and how to use HFSS and CST to complete the design and optimization ofthe generalized Chebyshev cross-coupled filter. The final simulation results and thetest results are verified the correctness of our works. |
