Random Access and Source-Channel Coding Error Exponents for Multiple Access Channels

A new universal coding/decoding scheme for random access with collision detection is given in the case of two senders. The result is used to give an achievable joint source-channel coding error exponent for multiple access channels in the case of independent sources. This exponent is improved in a modified model that admits error free 0 rate communication between the senders.Comment: This paper is submitted to IEEE transactions on information theory. It was presented in part at ISIT2013 (IEEE International Symposium on Information Theory, Istanbul