Suppression of carrier frequency offset and phase noise in adaptive bit loading OFDM system

Introduce adaptive bit loading technique into orthogonal frequency division multiplexing (OFDM) system can highly improve system performance in frequency selective fading channel. However, similar with ordinary OFDM system, this system is very sensitive to carrier frequency offset (CFO) and phase noise. When CFO and phase noise exist, common phase error (CPE) as well as inter carrier interference (ICI) will be generated to disturb the received signal and system performance will be seriously degraded. In this paper, we analyze the interferences caused by CFO and phase noise in adaptive bit loading OFDM system when the channel condition is frequency selective fading channel. Then the suppression method based on block type pilots is introduced to overcome the interferences simultaneously. From the simulation results, it can be seen that CFO and phase noise will cause serious system performance degradation. But after we perform the suppression processing, system performance can be significantly improved.

[1]  Hsiao-Chun Wu,et al.  Joint phase/amplitude estimation and symbol detection for wireless ICI self-cancellation coded OFDM systems , 2004, IEEE Transactions on Broadcasting.

[2]  Sven-Gustav Häggman,et al.  Intercarrier interference self-cancellation scheme for OFDM mobile communication systems , 2001, IEEE Trans. Commun..

[3]  Ana García Armada,et al.  Understanding the effects of phase noise in orthogonal frequency division multiplexing (OFDM) , 2001, IEEE Trans. Broadcast..

[4]  G.B. Giannakis,et al.  Blind carrier frequency offset estimation for OFDMA-based wireless networks , 2004, IEEE MILCOM 2004. Military Communications Conference, 2004..

[5]  Luciano Tomba,et al.  On the effect of Wiener phase noise in OFDM systems , 1998, IEEE Trans. Commun..

[6]  Jun Wu,et al.  A joint estimation algorithm of symbol timing and carrier offset in OFDM systems , 2001, IEEE VTS 53rd Vehicular Technology Conference, Spring 2001. Proceedings (Cat. No.01CH37202).

[7]  Ana García Armada,et al.  Phase noise and sub-carrier spacing effects on the performance of an OFDM communication system , 1998, IEEE Communications Letters.

[8]  Robert F. H. Fischer,et al.  A new loading algorithm for discrete multitone transmission , 1996, Proceedings of GLOBECOM'96. 1996 IEEE Global Telecommunications Conference.