Blind Symbol-Timing and Frequency-Offset Estimation in OFDM Systems With Real Data Symbols
| Autor: | M. Tanda |
|---|---|
| Přispěvatelé: | Tanda, Mario |
| Rok vydání: | 2004 |
| Předmět: |
Estimation theory
Orthogonal frequency-division multiplexing Estimator Cyclic prefix Complex normal distribution symbols.namesake Electronic engineering symbols Frequency offset Electrical and Electronic Engineering Gaussian process Algorithm Multipath propagation Computer Science::Information Theory Mathematics |
| Zdroj: | IEEE Transactions on Communications. 52:1609-1612 |
| ISSN: | 0090-6778 |
| DOI: | 10.1109/tcomm.2004.836438 |
| Popis: | In this letter, the problem of blind symbol-timing and frequency-offset estimation in orthogonal frequency-division multiplexing (OFDM) systems with real data symbols is considered. Maximum-likelihood (ML) estimators for the parameters of interest have been derived by modeling the OFDM signal as a proper complex Gaussian random process. However, when data symbols belong to a real constellation, the received signal becomes an improper complex random process, and hence, previously mentioned estimators, termed cyclic prefix (CP) estimators, are not ML estimators. In this letter, minimum mean-squared error estimators exploiting the conjugate-symmetry property exhibited by the OFDM signal with real data symbols, termed MSR estimators, that greatly outperform CP estimators in additive noise channels, are derived. Moreover, a modified MSR symbol-timing estimator that can assure satisfactory performance in multipath fading channels is proposed. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
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