Analyzing the effect of the Front-end circuit for the FBAR sensor

The FBAR sensor can be affected severely by its front-end circuit, especially the phase noise; however, it has rarely been discussed up to now. Herein, we analyze the influence of phase noise in the front-end circuit on an FBAR humidity sensor. A frequency shift detecting system was designed combined with the theoretical calculation and Advanced Design System (ADS) simulation. The available range of frequency shift is seriously influenced by...