Abstract—Orthogonal frequency division multiplexing (OFDM) is sensitive to carrier frequency offset (CFO).This CFO mainly occurs because of the frequency mismatch in the transmitter and the receiver. As a result, the orthogonality between the subcarriers are destroyed causing not only the inter carrier interference (ICI) in a sub carrier but also a phase rotation in the received complex signal. Due to the phase rotation of the received data the receiver decode the data incorrectly. Several methods like self cancellation, modified self cancellation, pulse shaping, maximum Likelihood offset detection are developed to overcome the ICI problem. Self cancellation techniques are based on algorithms making use of symmetry and conjugate properties of the sub-carriers [1, 2]. But none of these methods ensure the reduction of phase rotation problem. In this paper we have proposed a self cancellation method which uses for sub carriers for a particular data transmission to reduce the Phase Rotation of the received signal. We have compared the phase rotation of the received signal with respect to the Carrier Frequency Offset (CFO) of our proposed scheme with the ICI Self Cancellation Schemes. From our simulation, we find that our proposed scheme provides less rotation to the received data for a particular CFO than any other schemes.
Index Terms—OFDM, Inter carrier interference, phase rotation error, carrier frequency offset
The authors are with the North South University, Dhaka, Bangladesh (e-mail: mrahman@northsouth.edu, preyomdey@yahoo.com, u_rabbi@yahoo.com).
Cite: Miftahur Rahman, Preyom Kanti Dey, and M. F. Rabbi Ur Rashid, "Improved ICI Self Cancellation Scheme for Phase Rotation Error Reduction in OFDM System," International Journal of Information and Electronics Engineering vol. 2, no. 2, pp. 210-212, 2012.