Hier finden Sie wissenschaftliche Publikationen aus den Fraunhofer-Instituten.

On the impact of mobility on the channel estimation in WiMax OFDMA-uplink

: Sezgin, A.; Jung, P.; Schellmann, M.; Halbauer, H.; Muenzner, R.


Institute of Electrical and Electronics Engineers -IEEE-:
IEEE 17th International Symposium on Personal, Indoor and Mobile Radio Communications, PIMRC 2006. Proceedings : 11-14 September 2006, Finlandia Hall, Helsinki, Finland
Piscataway, NJ: IEEE, 2006
ISBN: 1-4244-0329-4
5 S.
International Symposium on Personal, Indoor and Mobile Radio Communications (PIMRC) <17, 2006, Helsinki>
Fraunhofer HHI ()
broadband networks; channel estimation; frequency division multiple access; Gaussian processes; markov processes; mean square error methods; radio links; radiofrequency interference; wimax

The demand for wireless broadband access systems supporting mobility of the individual users has dramatically increased in recent years. To this end, we analyze the impact of user-mobility in the uplink of an OFDMA system on the performance of pilot-aided channel estimation. We analyze the mean square error (MSE) performance of two pilot-aided channel estimation schemes, the simple Gauss-Markov estimator and the optimal LMMSE estimator. We derive closed-form expressions for the MSE taking into account the impact of intercarrier-interference and time-variations of the channel. Different pilot allocation strategies are analyzed and their performances are compared. Finally, the results are illustrated by numerical simulations based on the WiMax 802.16e specifications.