Power Line carrier Communication (PLC) technology is widely used in electric power data acquisition system, most of them adopt Orthogonal Frequency Division Multiplexing (OFDM, Orthogonal Frequency Division Multiplexing) technology, and the asynchronous pulse noise and periodic impulse noise in the power line have a great influence on the performance of OFDM power system, especially the greatest influence on the reliability of the system, due to the bit error rate of the system. Aiming at this problem, this paper uses OFDM signal sparse time-domain, eliminates impulse noise on the sending signal in the receiving terminal, and reduces the the calculation amount of the receiver, which improves the reliability of the system. The simulation results show that the proposed equalizing scheme eliminates the influence of impulse noise effectively and reduces the bit error rate.