Necessary and Sufficient Condition for Gaussian Feedback Capacity to Increase
نویسنده
چکیده
The problem considered in this paper is whether the capacity of a discrete time Gaussian channel is increased by feedback or not. It is well known that the capacity of a white Gaussian channel under the average power constraint is not changed by feedback. In the previous paper [7] we gave some sufficient conditions under which the capacity of a non-white Gaussian channel is increased by feedback. In this paper we give the necessary condition under which the capacity of a non-white Gaussian channel with blockwise white noise is increased by feedback.
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