Abstract: This paper proposed an enhanced PCF named VPCF, VPCF improve the non-real time traffic transmission in contend period. Been polled in contention free period, stations piggyback the backoff timer’s values of the frames send in the coming contention period. By comparing the backoff timer’s values, point coordinator foresees and announces the collisions between stations. Stations that will collide with others use a mechanism named virtual collision mechanism (VCM) to avoid collisions. The performance of VPCF was investigated by simulations. Results showed that, in contention period, VPCF outperforms the PCF in terms of channel throughput efficiency and collision rate while does not impact the real-time traffic transmissions in contention free period.