Visible light communication of an access credential in an access control system

An electronic locking device for multi-channel wireless communications and responsive to a light-emitting diode (LED) of a smart device so as to unlock an entry point in response to receiving, through a first communication channel, authentication information conveyed from the LED to the electronic locking device, the electronic locking device comprising:

• a wireless communication circuitry configured to provide a second communication channel, different from the first communication channel, to exchange access control information, the access control information including stored authentication and audit trail information for respectively, updating and reviewing user access of the electronic locking device;
• a memory for storing the access control information made available to the electronic locking device through the wireless communication circuitry;
• a photodetector arranged to confront a user holding the smart device so as to receive, through the first communication channel, an optical signal emitted as a sequence of user-perceptible flashes of light by a touchscreen or a camera flash including the LED, the sequence of user-perceptible flashes of light comprising a first flash of light having a first wavelength in a visible light spectrum and a second flash of light having a second wavelength in the visible light spectrum, the second wavelength being different than the first wavelength, whereby the difference between the first wavelength and the second wavelength results in a corresponding difference in output of the photodetector, and thereby produce, from the user-perceptible flashes of light, an electrical signal corresponding to the optical signal, the optical and electrical signals each representing the received authentication information;
• and
• electrical circuitry that, in response to the electrical signal, determines from it the received authentication information and compares it to the access control information stored in the memory operatively associated with the electrical circuitry so as to unlock the entry point in response to the received authentication information corresponding to the stored authentication information thereby permitting access to the user holding the smart device.