Time tracking loops for a communication system utilizing a cyclic prefix
US8416733B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jun 28, 2010 |
| Grant date | Apr 9, 2013 |
| Priority date | — |
| Expiry date | May 12, 2031 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L27/2665
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
Techniques for performing time tracking in a communication system utilizing a cyclic prefix are described. In an aspect, a receiver may detect for large timing errors based on early and late received samples obtained with early and late FFT windows, respectively. The receiver may derive first and second channel impulse response (CIR) estimates based on the early and late received samples, respectively, determine an early channel energy based on the first CIR estimate, determine a late channel energy based on the second CIR estimate, compute an update amount based on the early and late channel energies, and update the FFT window position based on the update amount. In another aspect, the receiver may perform time tracking with an inner time tracking loop (TTL) and an outer TTL. The receiver may update the FFT window position in coarse steps with the outer TTL and in fine steps with the inner TTL.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.