Method and apparatus for multipath delay estimation in direct sequence spread spectrum communication systems
US6839378B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 12, 1998 |
| Grant date | Jan 4, 2005 |
| Priority date | — |
| Expiry date | Sep 15, 2020 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04B1/7113
- WIPO fieldTelecommunications
- WIPO sectorElectrical engineering
Abstract
Multipath delay estimation of a direct sequence spread spectrum (DS-SS) signal transmitted in a multipath fading channel is accomplished by measuring the envelope of the signal to determine a new delay estimate. Delay estimates are also obtained in ray strength order, by subtracting out the influence of the stronger rays on the weaker ones. This subtraction approach can be performed iteratively, allowing further refinement of the delay estimates. Delay estimates can also be determined by minimizing the mean square error (MSE) between a measured correlation function and a modeled correlation function. The minimum mean square error (MMSE) approach can performed iteratively, to further refine the delay estimates. Maximum likelihood (ML) delay estimates can also be obtained by exploiting side information regarding the transmit and receive pulse shapes.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.