The invention discloses a
physical layer key distribution method based on random beams and edge calculation. The method comprises the following steps of S1, setting a protection area, S2,
conducting channel estimation: enabling Bob to send a channel
estimation sequence to Alice, enabling Alice to estimate
uplink channel information according to the received information, and transposing the uplinkchannel information to obtain downlink channel information, S3, generating random beams: enabling Alice to generate random beams according to the downlink channel information, S4,
processing and sending a key symbol: enabling Alice to send a key symbol s(n) to Bob, S5, receiving signals: enabling Bob and Eve to receive signals sent by Alice, S6, conducting key
estimation: enabling Bob to estimatethe key symbol under the condition of neglecting a
white noise vector nA to obtain estimated key information, and S7, when n is equal to 1, 2,... L, repeatedly executing the steps S3 to S6 until the Bob obtains the key with L symbol lengths. The distribution of the
physical layer key can be realized through two times of communication interaction, and the time
delay and complexity caused by
key sharing are reduced.