Secret key generation based on signal power allocation optimisation

With the rapid development of wireless communication, the use of the inherent features of wireless channels to enhance and supplement existing security mechanisms has attracted widespread attention. In this work, a key generation scheme based on power allocation optimisation is proposed. The subchannel state information obtained from channel probing is employed to allocate signal power. Furthermore, an improved channel probing process is designed to implement the optimisation scheme of power allocation. Theoretical analysis and simulation results show that this optimisation scheme can obtain higher key capacity, and the superiority is more prominent when the signal-to-noise ratio is low. Besides, the key bits mismatch rate of the proposed optimisation scheme is decreased and the corresponding key generation rate is higher compared with the benchmark.