基于链式耦合振荡环的轻量级真随机数发生器

张源; 应海炫; 高凯; 叶锦; 王爽; 张吉良

doi:10.11999/JEIT260377

基于链式耦合振荡环的轻量级真随机数发生器

doi: 10.11999/JEIT260377 cstr: 32379.14.JEIT260377

南京邮电大学集成电路科学与工程学院南京 210023

基金项目: 国家自然科学基金联合基金重点项目(U24A20289)

详细信息

作者简介:
张源：男，讲师，研究方向为硬件安全与集成电路设计

应海炫：男，本科生，研究方向为集成电路设计

高凯：男，博士生，研究方向为硬件安全

叶锦：男，博士生，研究方向为硬件安全

王爽：男，博士生，研究方向为硬件安全

张吉良：男，教授，研究方向为集成电路硬件安全

通讯作者:
张吉良　zhangjiliang@njupt.edu.cn

中图分类号: TN402
计量
- 文章访问数: 14
- HTML全文浏览量: 5
- PDF下载量: 1
- 被引次数: 0
出版历程
- 修回日期: 2026-06-04
- 录用日期: 2026-06-04
- 网络出版日期: 2026-06-08

A Lightweight True Random Number Generator Based on Chain-Coupled Oscillation Rings

College of Integrated Circuit Science and Engineering, Nanjing University of Posts and Telecommunications, Nanjing 210023, China

Funds: National Natural Science Foundation of China under Grant No. U24A20289

摘要

摘要: 真随机数发生器(TRNG)作为一种重要的硬件安全原语，通过提取物理随机变量产生无法预测的真随机序列，为安全系统构建硬件可信根。然而，为了提升TRNG的随机性，往往需要引入大量熵源，导致整体硬件开销较高。为解决这一问题，本文提出一种基于链式耦合振荡环的轻量级TRNG。首先，通过推导伽罗瓦振荡环的状态方程，分析不规则振荡机理，为熵源电路设计提供指导。然后，设计延迟反馈异或环，以此构建链式熵源电路，并进行不规则振荡行为建模。最后通过实验验证，所提出的TRNG通过了NIST SP 800-22和NIST SP 800-90B测试，在Xilinx Artix-7 FPGA上的吞吐量为200Mbps，且硬件开销仅为11个LUT和4个DFF，在资源受限的轻量级场景具有良好的应用前景。
- 真随机数发生器 /
- 耦合振荡环 /
- 不规则振荡 /
- 轻量级 /
- XXX
Abstract: Objective With the rapid growth of the Internet of Things, 5G/6G, and satellite Internet, resource-constrained devices increasingly require high-quality random numbers for key generation, authentication, masking, and other security functions. Although pseudo-random number generators are efficient, their outputs may be predictable once the seed or internal state is compromised. True random number generators (TRNGs) offer a hardware root of trust by extracting entropy from physical randomness, but many existing designs rely on multiple entropy sources or complex post-processing, leading to increased area and power consumption. To address this issue, this paper proposes a lightweight TRNG based on chain-coupled oscillation rings for high-quality randomness with very low FPGA overhead. Methods Starting from the state evolution of a Galois oscillation ring (GARO), this work demonstrates that ideal matched-delay conditions can result in periodic and predictable oscillation. However, in practical circuits, delay mismatch, jitter, and process variation disturb the ideal evolution and can be exploited as entropy sources. On this basis, a compact delay-feedback XOR ring is proposed to enhance state uncertainty, introduce feedback competition, and improve randomness through inter-stage delay differences. In addition, a second-order oscillation ring is incorporated to eliminate the all-zero stop state and provide continuous excitation. Multiple rings are then chain-coupled, enabling adjacent rings to mutually interfere with one another and thereby generate stronger irregular oscillations. The proposed design is modeled in MATLAB and implemented on a Xilinx Artix-7 FPGA. Finally, we evaluate its performance by NIST SP 800-22, NIST SP 800-90B, bias, autocorrelation, and voltage-temperature robustness tests. Results and Discussions Simulation confirms that the proposed structure avoids stable periodic locking and produces sustained irregular oscillation. Experimental results show that the TRNG passes all NIST SP 800-22 tests and achieves an average minimum entropy of 0.9936 in NIST SP 800-90B test, outperforming conventional RO and GARO-based TRNGs under similar conditions. The measured bias is only 0.0228%, and the autocorrelation remains well below the threshold, indicating excellent statistical independence. The design also maintains high entropy over temperatures from 0 °C to 80 °C and supply voltages from 0.9 V to 1.1 V. Implemented on Artix-7, our proposed TRNG achieves 200 Mbps throughput using only 11 LUTs and 4 DFFs, with 0.108 W power consumption. Conclusions This paper presents a lightweight chain-coupled oscillation-ring TRNG that exploits delay mismatch, phase disturbance, and feedback competition to generate high-quality physical randomness. The theoretical analysis clarifies how practical nonidealities transform ideal periodic oscillation into irregular oscillation, providing a design basis for compact oscillator-based entropy sources. By combining delay-feedback XOR rings with chain-coupled mutual disturbance and continuous excitation, the proposed design enhances entropy while avoiding excessive hardware overhead and complex post-processing. FPGA implementation and statistical evaluations verify high entropy, low bias, and high randomness under voltage and temperature variations. Therefore, the proposed TRNG achieves high randomness quality and high throughput while effectively reducing hardware overhead, making it suitable for resource-constrained security applications such as IoT terminals, lightweight cryptographic modules, and embedded authentication systems.
- True Random Number Generator /
- chain-coupled oscillation ring /
- irregular oscillation /
- lightweight entropy source /
- hardware security

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图 1 GARO电路结构

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图 2 延迟反馈异或环及其等效电路

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图 3 链式耦合振荡环TRNG结构图

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图 4 随机行为模型验证结果

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图 5 比特流图像(像素尺寸500 × 2000)

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图 6 自相关函数测试结果

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图 7 电压与温度测试结果

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表 1 NIST SP 800-22测试结果

NIST SP 800‐22	P-value	Prop
Frequency	0.122325	9/10
Block Frequency	0.122325	10/10
Cumulative Sums*	0.534146	9/10
Runs	0.534146	10/10
Longest Run	0.739918	10/10
Rank	0.534146	10/10
FFT	0.534146	10/10
Non-Overlapping Template*	0.350485	10/10
Overlapping Template	0.534146	10/10
Universal	0.739918	10/10
Approximate Entropy	0.122325	10/10
Random Excursions*	0.122325	4/4
Random Excursions Variant*	0.534146	4/4
Serial*	0.350485	10/10
Linear Complexity	0.350485	10/10

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表 2 NIST SP 800-90B测试结果

NIST SP 800-90B	p-max	h-min
MCV	0.501419	0.995911
Collision	0.535156	0.901968
Markov	3.5811E-39	0.997772
Compression	0.5	1
t-Tuple	0.52187	0.938238
LRS	0.527233	0.923488
MultiMCW	0.500626	0.998193
Lag Prediction	0.501736	0.995001
MultiMMC	0.501556	0.995517
LZ78Y	0.500495	0.998571

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表 3 TRNG综合性能对比

TRNG结构	硬件平台	吞吐量(Mbps)	功耗(W)	硬件开销	能效
文献[26]	Artix-7	80	—	866LUTs	—
文献[27]	Artix-7	100	0.119	38LUTs / 121DFF	66.34
文献[28]	Artix-7	1.25	0.023	152 LUTs / 16 DFFs	0.36
文献[29]	Artix-7	275.8	0.049	24 LUTs / 33 DFFs	234.52
文献[30]	Artix-7	620	0.068	23 LUTs / 14 DFFs / 4 MUXs	396.42
文献[31]	Artix-7	150	0.124	12 LUTs / 10 DFFs	100.80
本文	Artix-7	200	0.108	11 LUTs / 4 DFFs	168.35

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