No-drift™ BAW-SMR: Over-moded reflector for temperature compensation

As more LTE bands are squeezed into the crowded global RF spectrum interference becomes a major concern. Some cases require profoundly steep transitions from passband to the tightly packed neighboring bands. The most demanding high frequency LTE bands may only be served with high-performance BAW resonators that have been temperature compensated to have essentially zero temperature drift. There is a variety of known challenges associated with the traditional temperature compensation techniques applied to BAW devices. This work will address those challenges and present a novel no-drift BAW-SMR using over-moded acoustic reflector layers. A solution for Band 30 utilizing the over-moded reflector will be presented.