In this paper, we first investigate the performance of the 3G WCDMA wireless channel, and we find a special character, that sometimes a sudden link blockage/ congestion happens and causes heavy throughput drops during a certain time in the given 3G channel. After getting the basic characteristics and information about the performance, a novel transmission control scheme is proposed based on the Gilbert wireless error model by analysis of the characteristics which we notice of the wireless channel. The proposed scheme takes into consideration of the link blockage/sudden congestion which last for a short time in the 3G networks, the packet loss rate, and congestion level to increase packet successful delivery rate, reduce congestion and to improve the overall performance in the 3G networks by a adjustable rate control mechanism. Extensive simulation results demonstrate that the proposed scheme is effective in rate control and in decreasing the congestion level.