Coding for Memoryless Multiple-Access Channels

摘要

The main objectives of this research were (1) to derive bounds on the achievable rates of codes for a special multiple-access channel called the adder channel; (2) to find various techniques for constructing efficient codes for the adder channel; and (3) to find practical methods for encoding and decoding these codes. Some significant progress on constructing synchronizable m-user uniquely decodable codes was made. The following results were obtained: (1) a necessary and sufficient condition for a block to be statistically synchronizable; (2) a tighter lower bound on the achievable rates of two-user uniquely decodable codes with synchronism maintained between the two encoders and between the decoder and the encoders; (3) a lower bound on the achievable rates of the synchronizable two-user uniquely decodable codes; and (4) methods for constructing synchronizable two-user uniquely decodable codes.