Effects of Mutual Coupling on Degree of Freedom and Antenna Efficiency in Holographic MIMO Communications

Abstract

The holographic multiple-input-multiple-output (MIMO) communications refer to the MIMO systems built with ultra-dense antenna arrays, whose channel models and potential applications have attracted increasing attentions recently. When the spacing between adjacent array elements is larger than half wavelength, the effect of mutual coupling can generally be neglected in current antenna designs. However, in holographic MIMO communications, the influence of strong mutual coupling on antenna characteristics is inevitable, resulting in distorted radiation patterns and low radiation efficiencies. In this paper, starting from the analytical correlation and efficiency models, we investigate how the mutual coupling affects the capacity of a space-constrained MIMO system from the aspects of degree of freedom (DOF) and antenna efficiency. The involved fundamental concepts of correlation, DOF, efficiency and mutual coupling are crucial for both antenna and wireless-communication engineers when designing emerging MIMO communication systems.

References in corpus (5)

• Multi-User Holographic MIMO Surfaces: Channel Modeling and Spectral Efficiency Analysis
• Electromagnetic Effective Degree of Freedom of a MIMO System in Free Space
• Pattern-Division Multiplexing for Multi-User Continuous-Aperture MIMO
• Approaching the Fundamental Limit of Orbital Angular Momentum Multiplexing Through a Hologram Metasurface
• Capacity-Driven Low-Interference Fast Beam Synthesis for Next Generation Base Stations

Cited by in corpus (4)

• Densifying MIMO: Channel Modeling, Physical Constraints, and Performance Evaluation for Holographic Communications
• Breaking the Degrees-of-Freedom Limit of Holographic MIMO Communications: A 3-D Antenna Array Topology
• Electromagnetic Modeling and Capacity Analysis of Rydberg Atom-Based MIMO System
• Electromagnetic Normalization of Channel Matrix for Holographic MIMO Communications