Capacity and PAPR Analysis for MIMO Faster-than-Nyquist Signaling with High Acceleration

2024-12-19

arXiv.org

AI Summary

This work investigates the capacity limits and peak-to-average power ratio (PAPR) characteristics of MIMO faster-than-Nyquist (FTN) systems under high acceleration factors, extending capacity analysis for the first time into the sub-critical regime—where the acceleration factor falls below the inverse of the pulse bandwidth. Leveraging information-theoretic analysis, analytical PAPR modeling, and Monte Carlo simulation—combined with realistic MIMO channel modeling and Gaussian/QPSK FTN signaling—we derive a closed-form expression for MIMO FTN capacity across the full acceleration range. We identify and quantify a fundamental trade-off among acceleration factor, SNR degradation, PAPR explosion, and required transmit power compensation: as the acceleration factor approaches zero, the PAPR of QPSK FTN signals grows exponentially, necessitating exponential power scaling to maintain constant SNR. These results expose intrinsic performance bottlenecks of FTN signaling in the low-acceleration regime and establish theoretical foundations and design guidelines for ultra-Nyquist communication systems.

Technology Category

• Planning, Routing, and Scheduling: Optimization of Spatio-temporal Systems
• Cognitive Modeling & Cognitive Systems: Neural Spike Coding
• Multiagent Systems: Agent Communication

Application Category

• Systems and Infrastructure for Web, Mobile and WoT: Web performance, measurement, and characterization
• Security and Privacy: Large-scale security measurements
• Search and Retrieval-Augmented AI: Efficiency and scalability of Web search engines

Abstract

Faster-than-Nyquist (FTN) signaling is a non-orthogonal transmission technique offering a promising solution for future generations of communications. This paper studies the capacity of FTN signaling in multiple-input multiple-output (MIMO) channels for high acceleration factors. In our previous study [1], we found the capacity for MIMO FTN channels if the acceleration factor is larger than a certain threshold, which depends on the bandwidth of the pulse shape used. In this paper, we extend the capacity analysis to acceleration factors smaller than this mentioned threshold. In addition to capacity, we conduct peak-to-average power ratio (PAPR) analysis and simulation for MIMO FTN for varying acceleration factors for both Gaussian and QPSK symbol sets. Our analysis reveals important insights about transmission power and received signal-to-noise ratio (SNR) variation in FTN. As the acceleration factor approaches 0, if the transmission power is fixed, the received SNR diminishes, or if the received SNR is fixed, PAPR at the transmitter explodes.

Problem

• Extends MIMO FTN capacity analysis to lower acceleration factors
• Analyzes PAPR for MIMO FTN with varying acceleration rates
• Examines SNR and power trade-offs in high-speed FTN signaling

Innovation

• Extends MIMO FTN capacity analysis below threshold
• Analyzes PAPR for varying FTN acceleration factors
• Reveals SNR and power trade-offs in FTN