Improved Generation Efficiency for Key Extracting From Wireless Channels
Physical layer secret key can be extracted from wireless fading channels based on Channel Quantization with Guardband (CQG). In this paper, the authors analyze the performance of the CQG protocol. Analytical closed-form expressions of Bit Error Rate (BER) and key generation efficiency are derived for the CQG protocol. In order to further improve the key generation efficiency, they concatenate the CQG protocol with reconciliation. Then, they present an upper bound of key generation efficiency, which can be maximized by careful selecting the guardband region and LDPC code rates.