To enhance the video transmission security of a physical layer over wireless optical communication, an optical switch configured in front of an arrayed waveguide grating (AWG) router is proposed for implementing reconfigurable wavelength hopping configuration over a wavelength division multiplexing network for protection against eavesdropping. In the practical experiment of an AWG/optical-switch-based random wavelength hopping scheme, a simulated pseudorandom noise generator algorithm was designed and embedded into a master–slave microprocessor (e.g., Arduino chips) to generate a time series of electrical signals for triggering an optical switch. The path of the optical switch was randomly varied to change the space transmission of the AWG router. Therefore, varying wavelengths were assigned as the carriers of authorized users to realize the AWG/optical-switch-based wavelength hopping scheme. An optical spectrum analyzer and an oscilloscope were used for monitoring measurement. The experimental results indicated that eavesdroppers cannot accurately interpret analog, digital, audio, and uncompressed high-definition multimedia interface signals of 10 MHz, 1 MHz, 3.125 MHz (encoded into 6.25 MHz), and 1.485 GHz, respectively. According to the experimental results, authorized and unauthorized users are characterized by a large difference in the retrieved energy signal, which ensures the safety and privacy of the proposed AWG/optical-switch-based reconfigurable wavelength hopping scheme over a wireless optical communication network.
A 5G C-RAN Optical Fronthaul Architecture for Hotspot Areas Using OFDM-Based Analog IFoF Waveforms