Feedback-controlled compensation of parameter fluctuations of mobile radio SAW IF channel filters

Surface Acoustic Wave (SAW) filters with high sidelobe suppression, steep passband skirts and small chip sizes are key components for channel selection in modern mobile communication systems. These filters are fabricated on highly stable quartz substrates with precise photolithographic techniques. However, unavoidable fabrication tolerances, temperature drift and aging require some design reserve for achieving a specific filter characteristic. We report on a new receiver design which overcomes these drawbacks and does not demand a design reserve, thus improving the filter performance drastically. As an essential part of this receiver we developed a new SAW device.<
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