A general method is proposed to reduce noise by combining signals. Different measurements of the same physical quantity often exhibit different noise levels in different frequency ranges. Hence, a single high-fidelity signal can be constructed by combining the low-noise parts of the signals in Fourier space. We demonstrate this method by reducing noise in the measured bead-to-bead distance in an optical tweezers setup.

Rev. Sci. Instrum.

Mashaghi, A., Vach, P. J., & Tans, S. (2011). Noise reduction by signal combination in Fourier space applied to drift correction in optical tweezers. Rev. Sci. Instrum., 82(11). doi:10.1063/1.3658825