FPGA-Oriented Design and Efficient Implementation of a Geometrically Tunable Multiscroll Conservative Chaotic System Without Equilibrium Points

Abstract

Although multiscroll conservative chaotic systems exhibit rich dynamical characteristics and hold great potential for secure communications, existing designs generally suffer from limited controllability and low hardware implementation efficiency. To address these challenges, this article proposes a novel 4-D multiscroll conservative chaotic system based on a nonlinear feedback structure constructed using the floor function. This original approach simplifies the system’s logical structure, facilitating efficient hardware modeling while enabling flexible control over the number, amplitude, and spatial distribution of scrolls in 3-D space. The system’s high complexity and coexisting behaviors are validated through dynamical analyses, including equilibrium point analysis, Poincaré sections, and Lyapunov exponents (LEs). To achieve efficient deployment of the chaotic system on field-programmable gate array (FPGA) platforms, this article first simplifies the hardware implementation logic of the feedback structure through the design of an algorithmic model based on bitwise operations. Subsequently, precise control of the system’s module signals is achieved through a finite state machine (FSM) design. The results of the resource comparison analysis indicate that the proposed model achieves a high throughput of 10.08 Gbps while consuming only 1051 look-up tables (LUTs). The lower energy efficiency is 0.0264 mW/Mbps. Hardware-software co-simulation and oscilloscope visual output confirm the numerical precision and hardware feasibility of the proposed system. Finally, this system is integrated with the ZUC stream cipher to construct a novel encryption core, enabling asynchronous ciphertext transmission as well as encryption and decryption functions, thereby demonstrating its potential for secure hardware applications.