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. 07, 2015
Filed:
Aug. 20, 2013
Applicant:
Tektronix, Inc., Beaverton, OR (US);
Inventors:
Daniel G. Baker, Beaverton, OR (US);
Lakshmanan Gopishankar, Portland, OR (US);
George W. Tusing, Portland, OR (US);
Assignee:
Tektronix, Inc., Beaverton, OR (US);
Primary Examiner:
Int. Cl.
CPC ...
H04L 5/12 (2006.01); H04B 17/00 (2006.01); H04N 17/02 (2006.01); H04L 27/38 (2006.01);
U.S. Cl.
CPC ...
H04B 17/006 (2013.01); H04N 17/02 (2013.01); H04L 27/38 (2013.01);
Abstract
Described are systems and methods of estimating a Signal-to-Noise (S/N) ratio of an input channel carrying a QAM signal. A Modulation Error Ratio (MER) is calculated for the input QAM signal, but uses only the centermost error values of a constellation of the input QAM signal in generating this modified MER. The modified MER accurately represents the S/N ratio of the input channel carrying the QAM signal. In this way the S/N ratio may be accurately determined using only the received I and Q components of the modulated QAM input signal itself.