Iterative channel estimation approach for space-time/frequency coded OFDM systems with transmitter diversity
Yükleniyor...
Dosyalar
Tarih
2004-06
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Assoc Elettrotecnica Ed Elettronica Italiana
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
Focusing on transmit diversity orthogonal frequency division multiplexing (OFDM) transmission through frequency selective channels, this paper pursues novel iterative channel estimation approaches for both space-frequency OFDM (SF-OFDM) and space-time OFDM (ST-OFDM) systems. Relying on the unifying signal model for SF-OFDM and ST-OFDM transmitter diversity systems, we develop computationally efficient, maximum a posteriori (MAP) channel estimation algorithms according to the MAP criterion. The algorithms require a convenient representation of the discrete multipath fading channel based on the Karhunen-Loeve (KL) orthogonal expansion and estimates the complex channel parameters of each subcarriers iteratively using the expectation-maximisation (EM) method. In order to explore the performance, the closed-form expression for the average symbol error rate (SER) probability is derived for the maximum ratio combiner (MRC). Furthermore, to benchmark performance of the MAP channel estimator, the modified Cramer-Rao bound of channel estimates is also derived. Finally, we provide simulation results studying the influence of delay spread, propagation parameters and modelling mismatch on the performance of channel estimation techniques. Simulation results confirm our theoretical analysis and illustrate that the proposed algorithms are capable of tracking fast fading and improving overall performance.
Açıklama
Anahtar Kelimeler
Maximum-likelihood, Fading channels, Expansion, Channel estimation, Orthogonal frequency division multiplexing, Channel estimator, Bandwidth, Broadband networks, Computer simulation, Decoding, Fast Fourier transforms, Matrix algebra, Probability, Wireless telecommunication systems, Iterative channel estimation, Maximum ratio combiner (MRC), Single-carrier modulation, Space-time block code (STBC)
Kaynak
European Transactions on Telecommunications
WoS Q Değeri
Q2
Scopus Q Değeri
N/A
Cilt
15
Sayı
3
Künye
Çırpan, H. A., Panayırcı, E. & Doğan, H. (2004). Iterative channel estimation approach for space‐time/frequency coded OFDM systems with transmitter diversity. European Transactions on Telecommunications, 15(3), 235-248. doi:10.1002/ett.969
