Study Of Microwave Filter Tuning And Intelligent Tuning Platform

With the rapidly development of modern wireless communications, Microwave Filter has been improved a lot as the frequency-selected element to release the spectrum resources. According to the application of powerful microwave EDA simulation software tools and introducing of novel materials and technologies, design of microwave filters becomes easier and faster than it is in the past. But there is still a important section restrict the R&D period, which we call filter tuning, especially in production of massive quantities of civil used communication equipments, traditional tuning operated by experienced workers seems out of date.In this paper, the author listed some already used filter diagnosis and tuning methods, analyzed their principle and formula derivation, gave tuning step and strategy respectively. Also the author contrast the precision of parameter extracted according to some examples of schematic equivalent schematics and measured response curves and proposed mixed method of reflection phase and group delay to tune either cascaded or cross coupled filters.Finally, the paper described the intelligent microwave filter tuning platform which integrated above methods into Matlab GUI and linked to Agilent 8719ES vector network analyzer by Agilent 82357A USB/GPIB adapter, and also gave an example that is about a 6 degree cross coupled filter designed himself.