High Performance In Power Frequency Hopping Filter

In wireless communications, the use of frequency-hopping military communications technology is one of the most important means of interference,and if the system which uses the appropriate center frequency bringing rapid change,the fast tracking forms of frequency hopping-filter system will be significantly improved the antijamming performance.Therefore frequency hopping communication is the main manner in modern military communication, become a research focus. This FH filter with small size, fast time, points and more narrow-band low-loss and the mid-power characteristics,it have a greater value in the frequency hopping communications. In this paper, frequency hopping filter as the research, including the resonant frequency of cavity filter calculation, design of cavity size, calculation and design in a fixed cavity load array of switched-capacitor, with the active circuit and the combination of passive circuit methods, the use of novel structure way, through the design simulation and optimization, to achieve mid-power in high-performance compact frequency hopping filter. Summarizes the design of such filters to study the details summarized as follows:The main hopping filter insertion loss and power of elements; were: frequency hopping filter cavity unloaded quality factor Qu analysis ,switching power and insertion loss analysis, insertion loss of load RF capacitance, insertion loss of dielectric substrate analysis.Describes the general coupled resonator filter design theory. Coupling matrix is derived using the coupling coefficient formula, and the adjacent resonator coupling coefficient extraction, as well as input and output external quality factor extraction. This as a theoretical basis, design and implementation of frequency hopping filter bandwidth and input and output VSWR.Describes the function of frequency hopping filter design nd implementation to proposed passive and active circuits using the method of combining the active switched-capacitor load to passive resonator, in order to achieve the function of frequency hopping filter. Introduced the use of three-dimensional electromagnetic simulation software HFSS, Planar circuit simulation software ADS such as excellent simulation platform, more detailed analysis of the resonant frequency hopping filter rod length, the coupling window position and size respectively, the coupling between the resonant frequency.Combined with specific technical requirements given frequency hopping filter cavity part and switched-capacitor part of the design example, and the corresponding simulation curve and some test results. And gives some of hopping filter principles and the specific digital circuits methods .