A low-complexity KL expansion-based channel estimator for OFDM systems
Yükleniyor...
Dosyalar
Tarih
2005-04-05
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Springer International Publishing
Erişim Hakkı
info:eu-repo/semantics/openAccess
Özet
This paper first proposes a computationally efficient, pilot-aided linear minimum mean square error (MMSE) batch channel estimation algorithm for OFDM systems in unknown wireless fading channels. The proposed approach employs a convenient representation of the discrete multipath fading channel based on the Karhunen-Loeve (KL) orthogonal expansion and finds MMSE estimates of the uncorrelated KL series expansion coefficients. Based on such an expansion, no matrix inversion is required in the proposed MMSE estimator. Moreover, optimal rank reduction is achieved by exploiting the optimal truncation property of the KL expansion resulting in a smaller computational load on the estimation algorithm. The performance of the proposed approach is studied through analytical and experimental results. We then consider the stochastic Cramér-Rao bound and derive the closed-form expression for the random KL coefficients and consequently exploit the performance of the MMSE channel estimator based on the evaluation of minimum Bayesian MSE. We also analyze the effect of a modelling mismatch on the estimator performance. To further reduce the complexity, we extend the batch linear MMSE to the sequential linear MMSE estimator. With the fast convergence property and the simple structure, the sequential linear MMSE estimator provides an attractive alternative to the implementation of channel estimator.
Açıklama
Anahtar Kelimeler
Channel estimation, MMSE estimation, OFDM systems
Kaynak
Eurasip Journal on Wireless Communications and Networking
WoS Q Değeri
Scopus Q Değeri
Q1
Cilt
2005
Sayı
2
Künye
Şenol, H., Çırpan, H. A. & Panayırcı, E. (2005). A low-complexity KL expansion-based channel estimator for OFDM systems. EURASIP Journal on Wireless Communications and Networking, 2005(2), 163-174. doi:10.1155/WCN.2005.163
