# Intelligent Reflecting Surface Assisted Multi-User Robust Secret Key Generation for Low-Entropy Environments

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## Abstract

**:**

## 1. Introduction

## 2. System Model

## 3. Joint User Allocation and IRS Reflection Parameter Adjustment Scheme

Algorithm 1 Rank algorithm of IRS allocation for Bobs scheduling. |

Input:${R}_{B}^{(i,j)}$Output:pair$pair=\varnothing $ for loop = 1:N $(i,j)=\underset{i,j?[1,N]}{\mathrm{argmax}}({\mathrm{R}}_{B}^{(i,j)})$ ${\mathrm{R}}_{B}^{}={\mathrm{R}}_{B}^{}\backslash ({\mathrm{R}}_{B}^{(i,:)}\mathrm{U}{\mathrm{R}}_{B}^{(:,j)})$ $pair=pairU(i,j)$ % Pair relationship between IRS reflection matrix and Bob end |

## 4. Simulation and Numerical Results

## 5. Conclusions

## Author Contributions

## Funding

## Institutional Review Board Statement

## Informed Consent Statement

## Data Availability Statement

## Conflicts of Interest

## References

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**Figure 3.**Comparison of the IRS-random algorithm and IRS-rank algorithm on channel correlation. The ‘rank & discrete mode’ gives the performance line using our rank algorithm under the discrete IRS mode; ‘random & continuous mode’ gives the performance line using random algorithm under the ‘continuous IRS mode’.

**Figure 5.**Comparison of the IRS-random algorithm and IRS-rank algorithm on the key disagreement rate.

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**MDPI and ACS Style**

Gao, Y.; Guo, D.; Xiong, J.; Ma, D.
Intelligent Reflecting Surface Assisted Multi-User Robust Secret Key Generation for Low-Entropy Environments. *Entropy* **2021**, *23*, 1342.
https://doi.org/10.3390/e23101342

**AMA Style**

Gao Y, Guo D, Xiong J, Ma D.
Intelligent Reflecting Surface Assisted Multi-User Robust Secret Key Generation for Low-Entropy Environments. *Entropy*. 2021; 23(10):1342.
https://doi.org/10.3390/e23101342

**Chicago/Turabian Style**

Gao, Yuwei, Dengke Guo, Jun Xiong, and Dongtang Ma.
2021. "Intelligent Reflecting Surface Assisted Multi-User Robust Secret Key Generation for Low-Entropy Environments" *Entropy* 23, no. 10: 1342.
https://doi.org/10.3390/e23101342