Evaluation of an achievable rate region for the broadcast channel

Ahwc-The problem of transmission of separate messages to each of two receivers over a general binary-input broadcast channel is investigated. A new approach to a class of information-t problems is developed and applied to obtain boonds on the cardinalitiea of aoxiliary random variables. These bounds permit the calculation of two different regions of achievable rate pairs which are derived from the Cover-van der Meulen region 5% of achievable rate triples. Numerical evaluation of these regions of rate pairs for two examples demonstrates that the region ‘3, can be enlarged. Tbis enlargement is accomplii by making % internally consistent, as tbe true capacity region most be. The results display complex interactions between common and separate ioformation in broadcast problems.