Single-scan editor of bird echoes
US4963888A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Nov 3, 1988 |
| Grant date | Oct 16, 1990 |
| Priority date | — |
| Expiry date | Nov 3, 2008 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG01S13/534
- WIPO fieldMeasurement
- WIPO sectorInstruments
Abstract
A single-scan editor of bird echoes uses range rate to aid in identifying bird echoes. The range rate is preferably calculated from change in phase between one interpulse period to the next interpulse period and both unfiltered and MTI filtered signals are used for the calculation of change in phase. The unfiltered phase difference is used if the logarithm of the total power of the phase difference exceeds a predetermined threshold during at least one of the interpulse periods and if not, the MTI filtered phase difference is used if the total power of the MTI filtered signal exceeds a corresponding predetermined threshold. If neither threshold exceeds the corresponding threshold, no calculation is made. Due to the relationship between phase difference and range rate, several possible range rates correspond to most phase differences. Therefore, an occurrence of each of the possible range rates is counted over the course of a cycle. The cycle covered is shifted one interpulse period at a time and the largest number of occurrences of sets of range rates for all such cycles are stored during the detection of a target. These largest number of occurrences are totaled to produce a total c…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.