The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Apr. 15, 2014
Filed:
Aug. 05, 2009
Wesley Philip Wong, Cambridge, MA (US);
Kenneth Anders Halvorsen, Natick, MA (US);
Wesley Philip Wong, Cambridge, MA (US);
Kenneth Anders Halvorsen, Natick, MA (US);
President and Fellows of Harvard College, Cambridge, MA (US);
Abstract
Methods, apparatus and systems for determining a power spectral density (PSD) of a signal, in which modulation of the signal is employed to facilitate determination of one or more PSD values over a wide range of frequencies. In some implementations, the signal may represent a wide-sense stationary random process. In one example, the signal is measured/sampled during a plurality of measurement windows, during which an intensity of the signal is modulated at one or more modulation frequencies. A variance of a set of quantities determined from the signal samples is calculated and used to determine respective values of the power spectral density (PSD) for the signal at the one or more modulation frequencies. The one or more modulation frequencies may be chosen in excess of the Nyquist frequency of the sampling process, such that the signal may be characterized for one or more frequencies above the Nyquist limit.