Non-stationary dither code generation and detection
US6965634B1 · kind B1 · utility
Assignee
Inventor
Key dates
| Filing date | Nov 13, 2000 |
| Grant date | Nov 15, 2005 |
| Priority date | — |
| Expiry date | Apr 5, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/70735
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
A detector receives a signal and detects from it a long code composed from shorter codes, where the shorter codes are dithered according to a non-repeating dither pattern. The received signal is correlated with a reference code, the correlation sums are ranked, and short codes detected from the ranked sums. Because of a high jamming to signal (J/S) ratio, all the transmitted short codes may not be detected. A dither matching algorithm determines an interval between the detected codes and matches it with a previously stored dither pattern. If there is a strong match, the correlation sums and respective receive times are stored in a hypothesis data structure. If enough subsequent correlation pair have similar matches to exceed a threshold, the match is declared correct and the results are output. The time difference between received and matched pairs can be a measure of a pseudorange between transmitter and receiver.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.