Author : Rashi Sharma and Neeraj Shrivastava

Orthogonal frequency division multiplexing (OFDM) is a parallel transmission method, where single data stream is separated into a number of lower rate subcarriers, and each carrier is orthogonal to all other carriers. One of the main problems for OFDM system is Carrier frequency offset (CFO). OFDM is sensitive to CFO, which spoils the orthogonality between the sub-carriers, and cause Inter-carrier interference (ICI) in the OFDM, which corrupts the overall performance of OFDM and creates the frequency difference between the local oscillators of the transmitter and receiver, and the signals transmitted on each carrier are not independent of each other. In this paper, we introduce the analysis for calculating the Spectral Efficiency of OFDM systems with CFO. We further present the bit error rate (BER) performance of OFDM system with various CFOs under additive white gaussian noise (AWGN). This paper presents, the CFO in OFDM and the analysis for calculating the effect of the various CFOs on the performance of the OFDM system in term of BER under AWGN. Finally, in this paper, the results are sufficient to prove the Spectral Efficiency analysis and BER performance of OFDM system with various CFOs in AWGN channel.

Keywords: Orthogonal frequency division multiplexing (OFDM), Carrier frequency offset (CFO), Intercarrier interference (ICI), Spectral efficiency (SE), Bit error rate (BER), Signal-to-noise ratio (SNR), Additive white Gaussian noise (AWGN)

Article published in International Journal of Current Engineering and Technology, Vol.5, No.6 (Dec-2015)