We introduce various measures of forward classical communication for bipartite quantum channels. Since a point-to-point channel is a special case of a bipartite channel, the measures reduce to measures of classical communication for point-to-point channels. As it turns out, these reduced measures have been reported in prior work of Wang et al. on bounding the classical capacity of a quantum channel. As applications, we show that the measures are upper bounds on the forward classical capacity of a bipartite channel. The reduced measures are upper bounds on the classical capacity of a point-to-point quantum channel assisted by a classical feedback channel. Some of the various measures can be computed by semi-definite programming.
翻译:我们为两边量子频道引入了多种前方古典通信措施。由于点对点频道是两边频道的一个特例,因此这些措施减少为点对点频道的古典通信措施。事实证明,王等人先前在限制量子频道的古典能力的工作中报告了这些减少措施。作为应用,我们表明这些措施是双边频道前方古典能力的上限。减少措施是由古典反馈渠道协助的点对点量频道古典能力的上限。有些措施可以通过半定式程序计算。