Performance Analysis of Holographic MIMO Based Integrated Sensing and Communications

2024-01-25

IEEE Transactions on Communications

AI Summary

Conventional MIMO integrated sensing and communication (ISAC) and frequency-division holographic schemes suffer from performance bottlenecks in jointly optimizing communication and sensing under dynamic, spatially correlated channels. Method: This paper proposes a unified modeling framework for holographic MIMO ISAC (HISAC), jointly characterizing uplink/downlink communication channels with spatial correlation and spherical-wave sensing channels. It establishes dual-paradigm design—sensing-centric and communication-centric—and derives closed-form theoretical bounds on sensing rate, communication rate, and outage probability. A novel rate-region analysis method based on uplink interference cancellation ordering is introduced. Contribution/Results: The work reveals the coupling mechanism between high-SNR slope and diversity order in joint performance. Theory and simulations demonstrate that HISAC significantly outperforms conventional MIMO-ISAC and frequency-division holographic approaches in joint sensing–communication performance, validating both Pareto-optimal trade-offs and time-sharing strategies.

Technology Category

• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Search and Optimization: Mixed Discrete/Continuous Search
• Intelligent Robots: Multimodal Perception & Sensor Fusion

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Novel mobile and WoT systems, and system-of-systems
• Security and Privacy: Large-scale security measurements
• Semantics and Knowledge: Methods to enhance, augment, integrate or synergize semantic models such as knowledge graphs and LLMs

Abstract

A holographic multiple-input multiple-output (MIMO)-based integrated sensing and communications (ISAC) framework is proposed for both downlink and uplink scenarios. The spatial correlation is incorporated into the communication channel modeling, while a spherical wave-based model is used to characterize the sensing link. By considering both instantaneous and statistical channel state information, closed-form expressions are derived for sensing rates (SRs), communication rates (CRs), and outage probabilities under various ISAC designs. This enables an investigation into the theoretical performance limits of the proposed holographic MIMO-based ISAC (HISAC) framework. Further insights are gained by examining the high signal-to-noise ratio (SNR) slopes and diversity orders. Specifically: i) for the downlink case, a sensing-centric (S-C) design and a communications-centric (C-C) design are investigated using different beamforming strategies, and a Pareto optimal design is proposed to characterize the attainable SR-CR region; ii) for the uplink case, the S-C design and the C-C design differ in the interference cancellation order between the communication and sensing signals, with the rate region obtained through a time-sharing strategy. Numerical results are provided to demonstrate that HISAC systems outperform both conventional MIMO-based ISAC systems and holographic MIMO-based frequency-division sensing and communications systems, underscoring the superior performance of the HISAC framework.

Problem

• Holographic MIMO
• Simultaneous Communication and Sensing
• Signal Strength Variation

Innovation

• Holographic MIMO
• Integrated Sensing and Communication
• Optimized Signal Transmission