Channel Key Extraction Scheme Using Asymmetric Intelligent Reflecting Surface Transformation

Abstract

In physical layer secret key generation (PLSKG), the threshold-based quantization scheme is usually used to convert the channel detection value into the initial key bits. However, the data near the threshold is easily disturbed by noise fluctuation, which will lead to an increase in the key disagreement rate(KDR). We proposed an IRS-assisted key generation scheme, which uses the asymmetric change of IRS to ameliorate the downlink channel environment, to reduce the key inconsistency after quantization. Monte Carlo simulation and numerical results showed that our proposed scheme is feasible.