Cross-correlator circuit
US4097801A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 15, 1977 |
| Grant date | Jun 27, 1978 |
| Priority date | — |
| Expiry date | Mar 15, 1997 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG04F10/00
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
In a system for measuring the time delay existing between two pattern related random signals of similar but not identical modulated characteristics, utilizing the techniques of cross correlation, two analogue input signals are digitally quantized into binary form according to signal polarity. The first or leading quantized signal is delayed by a series of sequential time intervals or sampling periods to provide a time controlled sequence of delayed leading-signals at equal intervals. These delayed leading-signals are compared by a multiplication technique with the quantized second or lagging-signal, the occurrence when the signals correspond being summed in a series of overflow counters. The rate of filling of the responsive counters is proportional to the respective degree of correspondence and leads to one counter overflowing first, being indicative of the most probable time delay between the two signals. A variable frequency oscillator is used to control the sampling period so that overflow takes place most often in a selected one of the series of counters. To improve the time delay resolution, and to utilize higher frequency components of the signals, once a definite indication…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.