TY - GEN
T1 - Decision feedback turbo equalization for OFDM over doubly selective channels
AU - Barhumi, Imad
PY - 2012/12/1
Y1 - 2012/12/1
N2 - In this paper we propose soft decision feedback equalization for OFDM transmission over doubly selective channels which is used for turbo equalization. The doubly selective channel is approximated using the basis expansion model (BEM). The decision feedback equalizer is obtained and updated for every sub-carrier that results in a per-tone decision feedback equalizer (DFE). Using the Gaussian approximation, expressions for the a posteriori log likelihood ratio (LLR) and the extrinsic LLR are derived for QPSK modulation. The channel BEM coefficients are used to design the feed forward and feedback filters, which are used to equalize the underlying channel simulated according to the BEM as well as according to Jakes' channel models. Numerical results for the bit error rate performance assuming the BEM and Jakes' channel models are shown to confirm our findings.
AB - In this paper we propose soft decision feedback equalization for OFDM transmission over doubly selective channels which is used for turbo equalization. The doubly selective channel is approximated using the basis expansion model (BEM). The decision feedback equalizer is obtained and updated for every sub-carrier that results in a per-tone decision feedback equalizer (DFE). Using the Gaussian approximation, expressions for the a posteriori log likelihood ratio (LLR) and the extrinsic LLR are derived for QPSK modulation. The channel BEM coefficients are used to design the feed forward and feedback filters, which are used to equalize the underlying channel simulated according to the BEM as well as according to Jakes' channel models. Numerical results for the bit error rate performance assuming the BEM and Jakes' channel models are shown to confirm our findings.
KW - Doubly Selective Channels
KW - ICI
KW - OFDM
KW - Soft-Output DFE
KW - Turbo Equalization
UR - http://www.scopus.com/inward/record.url?scp=84877667112&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84877667112&partnerID=8YFLogxK
U2 - 10.1109/GLOCOM.2012.6503709
DO - 10.1109/GLOCOM.2012.6503709
M3 - Conference contribution
AN - SCOPUS:84877667112
SN - 9781467309219
T3 - GLOBECOM - IEEE Global Telecommunications Conference
SP - 3801
EP - 3806
BT - 2012 IEEE Global Communications Conference, GLOBECOM 2012
T2 - 2012 IEEE Global Communications Conference, GLOBECOM 2012
Y2 - 3 December 2012 through 7 December 2012
ER -