Improving the performance of ALOHA system utilizing coded multi-user detection

In this paper, a novel slotted ALOHA receiver, named coded ALOHA, is proposed, in which the multi-user detection is utilized under the condition of no spreading spectrum and interleavers are introduced as user's unique feature to separate the users. In the meantime, the utilization, the ratio of throughput and bandwidth expansion, and delay are used to evaluate the system performance. A comparison between CSMA, CDMA ALOHA with MD and the novel receiver is made and detailed theoretical analysis and computer simulation for these three kinds of receivers show that the novel receiver significantly improves the performance in term of delay and throughput. The utilization for coded ALOHA can reach 1.3 when SNR is 7.0 dB, highly greater than standard slotted ALOHA, 0.368, and CSMA, about 0.86.