Electromagnetic wave intrinsic orbital angular momentum covert communication system and method

The invention provides an electromagnetic wave intrinsic orbital angular momentum covert communication system and method, and relates to the technical field of communication. The method comprises the step of improving a communication mode of a signal transmitting subsystem end and a signal receiving subsystem end in the covert communication system. For a signal emission subsystem in a covert communication system, the method comprises the following steps: acquiring an encryption key and a main channel radio frequency signal; wherein the main channel radio frequency signal is a representation form of encrypted data obtained after user data is encrypted by using the encryption key; performing keying modulation according to the encryption key, and generating electromagnetic wave quantum state orbital angular momentum keying data corresponding to the encryption key; generating electromagnetic wave quantum state orbital angular momentum vortex microwave quantum according to the electromagnetic wave quantum state or