Abstract: The co-channel interference of Orthogonal Frequency Division Multiple Access has been the research focus for cellular mobile communication system. This paper analyzes and derives the mathematic expression of the system interference with considering the delay of signal domain , and verify the Co-Channel Interference (CCI) influence on the system with vary relative delay variances. In view of the limitations for co-channel due to the asynchronous non-correlative interference and the Interference Rejection Combining (IRC) and the advantages of convolutional code with small time delay and high coding gain Coded-IRC algorithm is presented to suppress interference. The simulation results show that the CCI resulting from delay decreases the system bit error rate performance, and the Coded-IRC algorithm overcomes the limitations of the IRC and improves the system bit error rate performance.