Aiming at the characteristics of wireless optical communication,a laser digital communication method based on baseband frequency hopping is proposed.The principles of single-fundamental and variable fundamental frequency modulation were analyzed.Frame structure of signals and implementation of ASK encoding and decoding in baseband frequency hopping laser communication were studied.Technical implementation of frequency hopping communication and control based on FPGA was discussed.In addition,the FPGA system was simulated and modulation and transmission experiments of variable fundamental frequency laser communication were carried out.The results show that the security of information transmission can be guaranteed by using variable fundamental frequency ASK modulation and encoding,and communication control and character data transmission in the visual range can be realized,which provides a new technical approach for the application of atmospheric laser communication.