Non-coded rateless multiple access

We present a novel random multiple access scheme called non-coded rateless multiple access (NC-RMA), in which each user keeps on sending its non-coded data packet with a predetermined probability at each time slot, until the receiver retrieves the data packet from a potentially infinite number of possibly collided packets. From a systematic point of view, the channel output resembles a special distributive rateless code with a binomial degree distribution, thus could be decoded in a similar way as for general rateless codes, making the channel access highly flexible and fully decentralized. Considering the superposition operation conducted by the channel, a modified iterative multi-user detection algorithm is proposed, and its high efficiency in noisy channel is analyzed by Extrinsic Information Transfer (EXIT) theory. Simulation results show that, the proposed scheme has much better performance than conventional random access schemes.