On Superposition Coding Based Cooperative Diversity Schemes
Anil Kumar Goparaju, Shuangqing Wei, Youjian Liu · 2006
Abstract — We propose two-level superposition coding based relaying schemes in which optimal power and rate allocations are investigated. Instead of confining us with fixed decoding order, two-levels of signals are considered as virtual users in a two-user multiple access channel and we prove that in certain cases the optimal joint multiuser decoding is equivalent to an approach using successive interference cancellation in a fixed order. Numerical results are provided to show the improvements in power savings using our proposed strategies compared with fixed rate and single level coding approach. I.