Asymmetric Stream Allocation and Linear Decodability in MIMO Coded Caching

2026-03-06

AI Summary

This work proposes a MIMO coded caching transmission and scheduling framework that supports asymmetric stream allocation, overcoming the limitations of conventional symmetric approaches which restrict the optimization of linear decodability and degrees of freedom (DoF) across all signal-to-noise ratio regimes. By establishing a user-specific stream allocation–based criterion for linear decodability, the framework breaks the symmetry constraint and expands the feasible DoF region. Integrating bit-level coded caching, linear receiver design, and a heuristic scheduling algorithm, the proposed scheme achieves significantly improved DoF performance while maintaining low decoding complexity, outperforming traditional symmetric strategies.

Technology Category

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

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Data management and stream processing for Web, mobile and wireless applications
• 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

Coded caching (CC) can transform cache memory at network devices into an active communication resource. Prior studies have shown that CC can significantly enhance the achievable Degrees of Freedom (DoF) in multi-input multi-output (MIMO) systems. To fully exploit MIMO-CC gains across all SNR regimes and enable practical linear receivers, flexible scheduling is required. Existing DoF analysis, scheduling, and linear receiver design, however, largely assume symmetric stream allocations across users. This paper extends the authors'recent work on DoF and linear decodability analysis for MIMO-CC systems by deriving a simple criterion, based on per-user stream allocation, that guarantees linear decodability for both symmetric and non-symmetric bit-level CC schemes. Building on this, we propose a heuristic MIMO-CC delivery and scheduling framework that enables asymmetric stream allocation while adhering to linear decodability, thereby expanding the feasibility region of achievable DoF compared to symmetric-constrained designs.

Problem

• MIMO
• coded caching
• asymmetric stream allocation
• linear decodability
• Degrees of Freedom

Innovation

• asymmetric stream allocation
• linear decodability
• MIMO coded caching
• Degrees of Freedom
• scheduling framework