OPTIMUM BINARY SIGNAL DETECTIONS FOR ERROR PROBABILITY AND MUTUAL INFORMATION

摘要

Optimizing a signal detection process to minimize the error probability or to maximize the mutual information is one of the most interesting subject to implement super-reliable communication systems, quantum computers, etc. The optimum detection operators which are the mathematical description of the optimum signal detection process have been derived for some signal quantum states in the case of the error probability. However, in the case of the maximum mutual information, the derivation of the optimum detection operators have been much difficult.rnRecently, one of authors proposed new algorithm to derive the optimum detection operators for both cases, where it is revealed for the binary pure state signal that both the optimum detection operators are identical while the conditions to be optimum are different. In this paper, we extend the investigation to the binary mixed state signals. It will be shown that both the optimum detection processes for the error probability and the mutual information are different except for some cases.