SAW devices in wireless communication systems

This paper discusses SAW applications in wireless communication systems. Recent developments in SAW resonator technology have made it possible to design and economically manufacture devices with very low insertion losses. One-port resonators with insertion losses of 1 to 2 dB and chip sizes similar to the former higher loss units are receiving widespread acceptance in the wireless marketplace. Closely related are very low loss SAW coupled resonators with losses of from 1 to 3 dB that are finding applications in simple oscillators and as narrowband filters. A resonator-based device that takes advantage of this low insertion loss is the proximity-coupled filter used primarily in narrowband IF applications. Finally, the single phase unidirectional transducer (SPUDT) low loss SAW transversal filter technology has advanced steadily in recent years