Equivocation limits in Gaussian additive channels
Abstract
Equivocation in a Gaussian additive channel is defined as H(X/X + Z(subt)) or as the conditional entropy of X entry and X + Z (subt) exit of the channel. Equivocation is obviously a function of t power of additive Gaussian interference Z(subt). The upper and lower limits of equivocation as the function of interference power t are investigated. The lower limit passes the concavity of entropy power in the function of additional interference power. This limit has numerous uses in information theory: it permits establishment of the optimality of two extreme points of the general Gaussian interference channel. The upper limit is a consequence of the inequality of Shannon entropy power. This limit establishes the fact that the very rapid increase in equivocation is logarithmic.
- Publication:
-
NASA STI/Recon Technical Report N
- Pub Date:
- July 1983
- Bibcode:
- 1983STIN...8513137C
- Keywords:
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- Communication;
- Concavity;
- Gauss Equation;
- Information Theory;
- Convolution Integrals;
- Entropy (Statistics);
- Vectors (Mathematics);
- Communications and Radar