Equation based TCP-friendly rate control （TFRC） protocol has been proposed to support video streaming applications In order to improve TFRC performance in wireless channels, the link level automatic repeat request （ARQ） scheme is usually deployed. However, ARQ cannot ensure strict delay guarantees, especially over multihop links. This paper introduces a theoretical model to deduce an equation for packet size adjustment in transport layer to minimize retransmission delay by taking into consideration the causative reasons inducing retransmission in link layer. An enhanced TFRC （ETFRC） scheme is proposed integrating TFRC with variable packet size policy. Simulation results demonstrate that higher goodput, lower packet loss rate （PLR）, lower frame transmission delay and jitter with good fairness can be achieved by our proposed mechanism.