Carrier Frequency Offset Estimation and Compensation Technique Based on Pilot Tones for OFDM Wireless Communication Systems

Orthogonal Frequency Division Multiplexing (OFDM) technology provides many benefits to wireless communication systems. However, the orthogonality of OFDM's subcarriers may be broken due to Carrier Frequency Offset (CFO) which causes a reduction in system efficiency. In this paper, a pilot-based CFO estimation and compensation algorithm is proposed to address the CFO issue in OFDM wireless communication systems. Pilot tones are inserted into the OFDM subcarriers on transmitters and then removed to estimate the CFO on receivers. The estimated CFO will be compensated in the time domain. The OFDM systems are simulated over the Rayleigh channel with different modulation levels and a different number of pilot tones. We find that the bit error rate (BER) of the OFDM systems applying our proposed method is dramatically improved by low modulation order and is not affected by the number of inserted pilots. As a result, our technique can save the resources for the OFDM systems. Moreover, the proposed solution outperforms the existing ones for CFO estimation and compensation.