A retransmission algorithm with dynamic linear combination based on network coding in wireless multicast networks

A retransmission algorithm with dynamic linear combination based on the network coding is proposed to meet the demands for decreasing the packets retransmission, to overcome the wireless channel fading, to build reliable wireless connection and to improve the efficiency of the bandwidth utilization in multicast networks. A dynamic linear combining coding algorithm (DLCCA) is used in the algorithm. Firstly, the transmitter in DLCCA sends original packets to users in the network. Then, the transmitter obtains the receiving status feedback from the users through control channel, and encodes the original packets that have not been correctly decoded by the users. Meanwhile, the encoding strategy is dynamically adjusted based on the network status so that the network throughput is improved. Furthermore, a coding algorithm with lower complexity is proposed, and the performance of the coding algorithm is analyzed. Theoretical result is obtained through analysis. Simulation results and comparisons with the transmission algorithm without network coding and the traditional XOR network coding algorithm show that the proposed algorithm greatly reduces 30% of packet retransmission, and the network throughput is increased.