Abstract: HSDPA is the solution to the high speed downlink packet services in UMTS. The max C/I scheduling is one of its scheduling algorithms. Two different scheduling algorithms, thorough max C/I and retransmission priority max C/I, were simulated, andthe relation curve of the maximum number of retransmission and FER was obtained. When the maximum number of retransmission is low the performance of thorough max C/I is better than retransmission priority max C/I, and when maximum number of retransmissionis high the performance of retransmission priority max C/I is better than thorough max C/I. The cause of the simulation results was also analyzed.

Key words: max C/I scheduling algorithm, high speed downlink packet access, maximum number of retransmission