Comparison of two methods of time-interval measurement based on SAWF and SAWDDL

In this paper, we demonstrate our work details on two methods of time-interval measurement based on SAWF (Surface Acoustic Wave Filter) and SAWDDL (Surface Acoustic Wave Dispersive Delay Line) and compare which one is easy and precise to be implemented. The two methods are based on the fact that transversal SAW components can be used as the time interpolator to reach precise time interval measurement which is much shorter than the sampling period. We have done an experiment using SAWF as the time interpolator in time-interval measurement with low frequency sampling clock which can be implemented easily on hardware platform and the result shows that the time interval measurement is about 2ps precision and stability.