Exploiting Spatial Multiplexing Based on Pixel Antennas: An Antenna Coding Approach

2025-12-05

AI Summary

To address the limited spatial multiplexing capability of conventional MIMO systems, this paper proposes a beam-domain antenna coding scheme based on pixel antennas. By dynamically controlling the RF switch states within pixel units, the radiation pattern is flexibly reconfigurable. We introduce, for the first time, a collaborative architecture comprising an “antenna encoder” and a “pattern encoder” to exploit additional degrees of freedom in the beam domain. Integrating reconfigurable radiating unit design, beam-domain MIMO modeling, and optimized pattern coding algorithms, the approach significantly enhances spatial multiplexing gain. Simulation results under a 4×4 configuration demonstrate a maximum spectral efficiency improvement of 12 bit/s/Hz—or equivalently, a 90% reduction in transmit power—achieving simultaneous capacity enhancement and energy efficiency optimization.

Technology Category

• Cognitive Modeling & Cognitive Systems: Neural Spike Coding
• Search and Optimization: Sampling/Simulation-based Search
• Computer Vision: Multi-modal Vision

Application Category

• User Modeling, Personalization and Recommendation: On-Device user modeling, personalization, and recommendation
• Systems and Infrastructure for Web, Mobile and WoT: Energy management for devices in mobile Web and WoT environments
• Search and Retrieval-Augmented AI: Efficiency and scalability of Web search engines

Abstract

An antenna coding approach for exploiting the spatial multiplexing capability of pixel antennas is proposed. This approach can leverage additional degrees of freedom in the beamspace domain to transmit more information streams. Pixel antennas are a general reconfigurable antenna design where a radiating structure with arbitrary shape and size can be discretized into sub-wavelength elements called pixels which are connected by radio frequency switches. By controlling the switch states, the pixel antenna topology can be flexibly adjusted so that the resulting radiation pattern can be reconfigured for beamspace spatial multiplexing. In this work, we introduce the antenna coder and pattern coder for pixel antennas, provide a multiple-input multiple-output (MIMO) communication system model with antenna coding in the beamspace domain, and derive the spectral efficiency. Utilizing the antenna coder, the radiation pattern of the pixel antenna is analyzed and efficient optimization algorithms are provided for antenna coding design. Numerical simulation results show that the proposed technique using pixel antennas can enhance spectral efficiency of 4-by-4 MIMO by up to 12 bits/s/Hz or equivalently reduce the required transmit power by up to 90% when compared to conventional MIMO, demonstrating the effectiveness of the antenna coding technique in spectral efficiency enhancement and its promise for future sixth generation (6G) wireless communication.

Problem

• Proposes antenna coding for spatial multiplexing with pixel antennas
• Enhances spectral efficiency and reduces power in MIMO systems
• Optimizes reconfigurable radiation patterns for 6G wireless communication

Innovation

• Pixel antennas enable reconfigurable radiation patterns via RF switches
• Antenna coding exploits beamspace degrees of freedom for multiplexing
• Spectral efficiency enhanced by 12 bits/s/Hz in 4x4 MIMO systems