Nokia Bell Labs Publishes Research on Relay Broadcast Channel Capacity
Nokia Bell Labs has published research outlining capacity regions for relay broadcast channels. The publication presents new theoretical bounds and solutions for specific network configurations.
Nokia's research division, Nokia Bell Labs, released a detailed research paper titled "Rate Regions for Relay Broadcast Channels" on October 1, 2007. The publication delves into the theoretical capacity of partially cooperative relay broadcast channels (RBC).
The study examines a three-node network comprising one source and two destination nodes. It specifically analyzes the scenario where the first destination can act as a relay for the second destination. The paper establishes inner and outer bounds for the capacity region of discrete memoryless, partially cooperative RBCs.
When the relay function is disabled, the findings simplify to previously established inner bounds for broadcast channel capacity regions, which are at least as large as Marton's inner bound. The outer bound generalizes previous results by Marton and Gel'fand-Pinsker, accounting for both common and private message transmissions.
The research addresses four distinct classes of relay broadcast channels. Capacity regions are successfully determined for the partially cooperative RBC with degraded message sets, as well as for the semideterministic and orthogonal RBCs. Additionally, the paper presents the capacity region for a parallel relay broadcast channel with unmatched degraded subchannels, and for the case where the source node possesses only a private message for the second destination.