A Highly Consistent and High-speed Physical Layer Key Generation Scheme

There are some problems that the bit error rate is high but generation rate is low in existing physical layer secret key generation schemes, so we propose a highly consistent and high-speed secret key generation scheme in this paper. This scheme not only can achieve high consistency and high generation rate, but also can ensure randomness of secret key. First, the scheme conducts channel pre-detection to calculate weighted vectors to smooth the noise. Then, a modified level crossing algorithm is proposed to improve key consistency greatly. Furthermore, we put forward cyclic interleaving quantization method that can linearly improve key generation rate and enhance randomness of secret key. Simulation results show that the scheme can achieve zero bit disagreement, and key generation rate can reach at least 495% when SNR is 20 dB.