2012/05/18 by Changho Suh, Suh, Changho, Naveen Goela +3
Computer Science · Engineering · #Cooperative Communication and Network Coding #Error Correcting Code Techniques #FOS: Computer and information sciences #Information Theory (cs.IT) #Wireless Communication Security Techniques
paper · pdf · doi:10.48550/arxiv.1205.4168
openalex publication_date 2012/05/18 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
We characterize the capacity region to within log2(M-1) bits/s/Hz for the M-transmitter K-receiver Gaussian multicast channel with feedback where each receiver wishes to decode every message from the M transmitters. Extending Cover-Leung's achievable scheme intended for (M,K)=(2,1), we show that this generalized scheme achieves the cutset-based outer bound within log2(M-1) bits per transmitter for all channel parameters. In contrast to the capacity in the non-feedback case, the feedback capacity improves upon the naive intersection of the feedback capacities of K individual multiple access channels. We find that feedback provides unbounded multiplicative gain at high signal-to-noise ratios as was shown in the Gaussian interference channel. To complement the results, we establish the exact feedback capacity of the Avestimehr-Diggavi-Tse (ADT) deterministic model, from which we make the observation that feedback can also be beneficial for function computation.