Research On Ultraviolet Multi-channel Communication Technology

Ultraviolet communication (UVC) uses solar-blind ultraviolet (UV) light as the signal carrier and free space as the transmission medium. Compared with other types of wireless communication, UVC has the characteristics of small interference, good secrecy and non-line-of-sight communication which make UVC can be used in some special occasions. Therefore, UVC has great value of research.Research on UVC is still in its early stage with many key technical problems to be solved. Supported by National Natural Science Foundation of China,this paper mainly studies basic theory and experiment of UV channel model and UV MIMO communication systems. The mainly innovative work is as follows:(1) This paper proposes a multi-path based channel model which only needs to solve the parameters in the function and can give the channel impulse response and characteristics of channel delay. The proposed model has low computation complexity and easy to implement.(2) For the problem of low bit rate of UVC, the paper presents the scheme of ultraviolet MIMO technology, and carries out the off-line experiment. The experiment results show that the scheme can effectively double the bit rate.(3) In view of the problem of large path loss in UV channel, the paper proposes the scheme of modified Alamouti code based UV MIMO system and carries out both simulation and off-line experiment. Both the simulation and experiment results show that the modified Alamouti code based UV MIMO system can effectively reduce the bit error rate and improve the system performance.(4) To improve the performance of the system further, the paper combines the spread spectrum technology and the above modified Alamouti code based UV MIMO system, proposing a spread spectrum based MIMO system. And the simulation results show the spread spectrum based MIMO system can effectively reduce the bit error rate further.