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Hier finden Sie wissenschaftliche Publikationen aus den FraunhoferInstituten. Efficient channel estimation schemes for MIMO OFDM systems with NULL subcarriers
 Institute of Electrical and Electronics Engineers IEEE; IEEE Vehicular Technology Society VTS: IEEE 68th Vehicular Technology Conference, VTC 2008Fall. Proceedings. Vol.2 : Calgary, Canada, 21  24 September 2008 Piscataway/NJ: IEEE, 2008 ISBN: 9781424417216 ISBN: 9781424417223 ISBN: 142441721X S.659663 
 Vehicular Technology Conference (VTC Fall) <68, 2008, Calgary> 

 Englisch 
 Konferenzbeitrag 
 Fraunhofer HHI () 
 channel estimation; computational complexity; mimo communication; ofdm modulation 
Abstract
In this paper, channel estimation schemes as well as low crestfactor preamble construction are presented for practical MIMO OFDM systems with NULL subcarriers. In the presence of NULL subcarriers, the performance of the channel estimator in [1] degrades considerably. Therefore, Maximumlikelihood (ML) channel estimators were proposed for MIMO OFDM systems with NULL subcarriers [2], [3]. However, they have relatively high computational complexity. Thus, more efficient schemes are proposed in our paper, with regard to two different cases of NULL subcarrier usages: only DC subcarrier is null or both DC and high frequency subcarriers are null. Simulation results show that the new schemes achieve performances near the optimum error bound.