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Orthogonal Frequency Division Multiplexing (OFDM) is a promising technology for combating the frequency selective fading, multipath propagation, and narrowband interference in power line communication. However, OFDM systems are extremely sensitive to synchronization deviation. Slight synchronization deviation can affect the performance of OFDM systems. This paper presents a design and implementation synchronization algorithm based on constant amplitude zero auto-correlation (CAZAC) for power line communication. Matlab simulation prove that, with less computation, the proposed algorithm can complete symbol timing synchronization and frequency offset synchronization well and the performance of OFDM synchronization in power line communication is significantly improved. I. INTRODUCTION With the development of smart grid, power line communication technology has become one of the important techniques for smart grid construction. In order to improve transmission rate and reliability of the power line communication system, appropriate modulation and demodulation scheme should be used in power line communication. Orthogonal Frequency Division Multiplexing (OFDM)is an efficient modulation and multi-carrier transmission technology, and it has many advantages, such as high spectrum efficiency, excellent resistance to multipath propagation and fading ability, At the same time, it can also be effective against frequency selective fading, multipath propagation and noises in power line communication(PLC). OFDM systems not only sensitive to frequency offset and symbol timing error but also exceptionally strict orthogonality of sub-carriers. The orthogonality will be destroyed by small frequency offset; then the inter-channel interference (ICI) is introduced in the system that will cause the performance of OFDM systems sharp deterioration [1][2].The frequency offset is divided into integer frequency offset (IFO) and fractional frequency offset (FFO) by sub-carrier interval [3]. The fractional part will cause ICI, and the influence of integer part is reflected in the cyclic shift of output subcarrier [4].The data phase will be rotated when timing error exist in OFDM system, as a result, the inter-symbol interference (ISI) will be introduced. Therefore, accurate timing and frequency offset estimation are key issues in OFDM systems.

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