Method for determining echo distance using autocorrelation in time of flight ranging systems
US6856576B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Sep 29, 2003 |
| Grant date | Feb 15, 2005 |
| Priority date | — |
| Expiry date | Sep 29, 2023 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S367/908
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A method and system for echo processing a receive signal using autocorrelation. A receive signal is sampled, digitized and high-pass filtered. A correlation signal is created by adding the filtered signal to a copy of the filtered signal shifted by a time unit. A set of correlation signals is created by repeating the process for a range of time units corresponding to a set of sequential sample points. Each correlation signal has a correlation indicator evidencing the strength of the correlation. The correlation signal having the highest correlation strength is identified, and the time shift used to create it is identified as the time of flight of the echo pulse. The echo distance is then calculated based upon the time of flight and the speed of propagation of the echo in the environment. The correlation indicator may the maximum peak value of the correlation signal.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.