The degrees of freedom (DoFs) of the $K$ -user Gaussian interference channel determine the asymptotic growth of the maximal sum rate as a function of the signal-to-noise ratio. Subject to a very general sufficient condition on the cross-channel gains, we give a formula for the DoFs of the scalar interference channel as a function of the deterministic channel matrix, which involves maximization of a sum of information dimensions over $K$ scalar input distributions. Known special cases are recovered, and even generalized in certain cases with unified proofs.
All Science Journal Classification (ASJC) codes
- Information Systems
- Computer Science Applications
- Library and Information Sciences
- Multiuser information theory
- Shannon theory
- degrees of freedom
- high-SNR channels.
- information dimension
- interference channel
- sumset entropy inequalities