1 research outputs found
Multiple Access Analog Fountain Codes
In this paper, we propose a novel rateless multiple access scheme based on
the recently proposed capacity-approaching analog fountain code (AFC). We show
that the multiple access process will create an equivalent analog fountain
code, referred to as the multiple access analog fountain code (MA-AFC), at the
destination. Thus, the standard belief propagation (BP) decoder can be
effectively used to jointly decode all the users. We further analyse the
asymptotic performance of the BP decoder by using a density evolution approach
and show that the average log-likelihood ratio (LLR) of each user's information
symbol is proportional to its transmit signal to noise ratio (SNR), when all
the users utilize the same AFC code. Simulation results show that the proposed
scheme can approach the sum-rate capacity of the Gaussian multiple access
channel in a wide range of signal to noise ratios.Comment: To appear in IEEE International Symposium on Information Theory
(ISIT), Honolulu, HI, USA, 201