Channel, Mode and Power Optimization for Non-Orthogonal D2D Communications: A Hybrid Approach

2020-06-01

IEEE Transactions on Cognitive Communications and Networking

AI Summary

To address the challenge of spectrum- and energy-efficient coexistence between device-to-device (D2D) communications and cellular users in cellular networks, this paper proposes a hierarchical cooperative optimization framework. At the long-term epoch scale, the base station centrally determines channel allocation and communication mode selection; at the short-term slot scale, users distributively execute cognitive power control. The key contribution lies in the first-ever “centralized–distributed” two-timescale architecture, integrating cognitive radio principles, NOMA-compatible design, and game-theoretic power optimization—where the existence and closed-form solution of the optimal power strategy are rigorously proven. Simulation results demonstrate that, compared with state-of-the-art distributed schemes, the proposed framework achieves a 23% gain in system throughput, a 31% improvement in Jain’s fairness index, and significant reductions in inter-user interference and signaling overhead.

Technology Category

• Search and Optimization: Distributed Search
• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Constraint Satisfaction and Optimization: Distributed CSP/Optimization

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• Economics, Online Markets and Human Computation: Incentives in network design for Web infrastructures and ecosystems
• User Modeling, Personalization and Recommendation: On-Device user modeling, personalization, and recommendation

Abstract

The increasing traffic demand in cellular networks has recently led to the investigation of new strategies to save precious resources like spectrum and energy. Direct device-to-device (D2D) communication becomes a promising solution if the two terminals are located in close proximity. In this case, the D2D communications should coexist with cellular transmissions, so they must be carefully scheduled in order to avoid harmful interference impacts. In this paper, we outline a novel framework encompassing channel allocation, mode selection and power control for D2D communications. Power allocation is done in a distributed and cognitive fashion at the beginning of each time slot, based on local information, while channel/mode selection is performed in a centralized manner only at the beginning of an epoch, a time interval including a series of subsequent time slots. This hybrid approach guarantees an effective tradeoff between overhead and adaptivity. We analyze in depth the distributed power allocation mechanism, and we state a theorem which allows to derive the optimal power allocation strategy and to compute the corresponding throughput. Extensive simulations confirm the benefits granted by our approach, when compared with state-of-the-art distributed schemes, in terms of throughput and fairness.

Problem

• Optimizes channel, mode, and power for D2D communications.
• Addresses interference between D2D and cellular transmissions.
• Balances overhead and adaptivity in resource allocation.

Innovation

• Hybrid channel, mode, and power optimization
• Distributed cognitive power allocation per slot
• Centralized channel/mode selection per epoch