A system, method, apparatus, and means for generating timing information in a wireless communication network comprises detecting, at a mobile unit, accurate timing information, wherein the mobile unit is in a cell area serviced by a base station. Accordingly, even if the surface sloshes and the water level L0 fluctuates up and down, the water level L0 is smoothed by the filter. Furthermore, the first layer and the second layer each have a thickness of at most 100 \u03bcm, and at least one of the first backing and the second backing comprises a first elastic polymer.