Frequency offset estimation method for OFDM-IM system
US11140009B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 30, 2018 |
| Grant date | Oct 5, 2021 |
| Priority date | — |
| Expiry date | Oct 30, 2038 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04L2027/0026
- WIPO fieldDigital communication
- WIPO sectorElectrical engineering
Abstract
The invention provides a frequency offset estimation method for an OFDM-IM system. The method includes: S1. performing preliminary frequency offset compensation on a received signal subjected to non-uniform frequency offset by using a two-step method of: (1) resampling and down conversion; and (2) unified compensation for residual frequency offset ε, wherein in the step (2), a sum of energy of null sub-carriers is used as a cost function, an initial estimation value of ε is obtained by one-dimensional search, and the preliminary compensation is performed; S2. estimating positions of non-activated sub-carriers in the OFDM-IM system by using the signal subjected to the preliminary compensation; and S3. assigning certain weights to the estimated sub-carriers, adding energy of the estimated sub-carriers into the cost function according to different weights, obtaining a final estimation value of ε by the one-dimensional search performed on ε, and performing secondary compensation.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.