A narrow-band window using frequency dependant dielectric stacks

The use of dielectric stacks in radio frequency design is common. These stacks are often simplified to a volume average material to assist in the design process. This simplification, however, hides the frequency dependant nature of dielectric stacks. This paper illustrates the frequency dependence and highlights the cause and situations where it occurs. This frequency dependence is then exploited to design narrow-band window from a dielectric stack. This window has near total transmission and 0° phase delay at a particular frequency with high reflection outside the narrow-band transmission window.