| US 7,483,800 B2 | ||
| Peak detection and clutter reduction for a microwave sensor | ||
| Jonathan Geisheimer, Neyruz (Switzerland); and Thomas Holst, Villars-sur-Glâne (Switzerland) | ||
| Assigned to Radatec, Inc., Londonderry, N.H. (US) | ||
| Filed on Jun. 01, 2007, as Appl. No. 11/809,499. | ||
| Claims priority of provisional application 60/810105, filed on Jun. 01, 2006. | ||
| Prior Publication US 2008/0195338 A1, Aug. 14, 2008 | ||
| Int. Cl. G01R 23/16 (2006.01) | ||
| U.S. Cl. 702—77 [702/71; 702/73; 702/75; 702/76; 702/85; 702/87; 702/88] | 2 Claims |
| 1. A method for completing a blade measurement for rotating blades within a casing of a turbine engine, comprising the steps
of:
transmitting microwave energy via an antenna within the casing of the turbine engine;
collecting in-phase and quadrature data associated with the microwave energy reflected by the blades and the casing;
performing a complex Fast Fourier Transform (FFT) on the in-phase and quadrature data to generate positive frequency components
and negative frequency components;
separating the positive negative frequency components from the negative frequency components;
performing an inverse FFT on each of the positive frequency components and the negative frequency components to generate complex
time domain data associated with approaching and recessing velocity components;
converting the complex time domain data to magnitude and phase values, the magnitude values comprising approaching and recessing
magnitude values and the phase values comprising approaching and recessing phase values;
identifying each crossing of the magnitude values with a predetermined threshold to define a blade region associated with
a location for one of the blades proximate to the antenna;
for the blade region, identifying a zero point velocity as the point where one of the approaching phase values equals one
of the recessing phase values, the zero point velocity representing a location of the blade directly beneath the antenna;
and
processing blade data using the zero point velocity as an index.
|