This paper extends linear-complexity concatenated coding schemes to fountain communication over the discrete-time memoryless channel. Achievable fountain error exponents for one-level and multi-level concatenated fountain codes are derived. Several important properties of the concatenated coding schemes in multi-user fountain communication scenarios are demonstrated.

A new channel coding approach was proposed by Luo and Ephremides for random multiple-access communication over the discrete-time memoryless channel. The coding approach allows users to choose their communication rates independently without sharing the rate information among each other or with the receiver. The receiver will either decode the messages or report a collision depending on whether reliable message recovery is possible. It was shown that, asymptotically as the codeword length goes to infinity, the set of communication rates supporting reliable message recovery can be characterized by an achievable region which equals Shannon's information rate region without a convex hull operation. In this paper, we derive achievable bounds on error probabilities, including the decoding error probability and the collision miss detection probability, of random multiple-access systems with a finite codeword length. Achievable error exponents are obtained by taking the codeword length to infinity.

Random access communication is used in practical systems to deliver bursty short messages. Because users only transmit occasionally, it is often difficult for the receiver to keep track of the time varying wireless channel states. Under this motivation, we develop channel coding theorems for random multiple access communication over compound channels with finite codeword length. Error performance bound and asymptotic error probability scaling laws are derived. We found that the results also help in deriving error performance bounds for the random multiple access system where the receiver is only interested in decoding messages from a user subset.

In, a new channel coding approach was proposed for random multiple access communication over the discrete-time memoryless channel. The coding approach allows users to choose their communication rates distributively without sharing the rate information with each other and the receiver. The receiver makes decoding and collision report decisions depending on whether reliable message recovery is possible. It was shown that, asymptotically as codeword length goes to infinity, the set of communication rates supporting reliable message recovery can be characterized by an achievable region which equals Shannon's information rate region without a convex hull operation. In this paper, we derive stronger versions of the coding theorems in by characterizing how system error probability, defined as the maximum of decoding error probability and collision miss detection probability, approaches zero with respect to the codeword length.

This paper investigates fountain communication over discrete-time memoryless channels. Fountain error exponent achievable by linear complexity concatenated fountain codes is derived.