Optical wireless communication device and method applied to turbid media

Abstract

The invention discloses an optical wireless communication device and method applied to turbid media. The device comprises a mode-locked laser, a laser beam expander, a diaphragm, a beam splitter prism, a liquid crystal spatial light modulator, a telescope, a high-speed photodiode, a digital acquisition module and a computer, wherein the laser beam expander, the diaphragm, the beam splitter prism and the liquid crystal spatial light modulator are sequentially placed on the center axis of the output end of the mode-locked laser, and all optical centers are matched; the optical axes of the liquid crystal spatial light modulator and the telescope are crossed with each other; the high-speed photodiode is placed on a rear focal plane of the telescope; the signal output end of the high-speed photodiode is connected with the analog input end of the digital acquisition module by a coaxial cable, and the output end of the digital acquisition module is connected with a network port of the computer and uploads a data acquisition result. The method and the device can effectively inhibit the influence of turbid media on optical wireless communication, and realize communication with low bit error rate.

Description

Technical field [0001] The present invention belongs to wireless optical communication technology, in particular to an optical wireless communication device and method applied in chaotic media. Background technique [0002] Optical wireless communication, including free space optical-communication (FSO) and visible light communication (VLC), has the advantages of wide spectrum, high transmission rate, no spectrum certification, anti-electromagnetic interference, strong confidentiality, and easy deployment. It has been widely used and concerned in the military and commercial fields. At present, optical wireless communication is mainly a point-to-point transmission mode, that is, the transmitting end is transmitted by a single-port photoelectric conversion module to transmit an encoded optical pulse, and the receiving end barrel detector obtains the pulse through the telescope system, and decodes it through the back-end computing module. Communication. The transmission quality of...

AI Technical Summary

Problems solved by technology

For chaotic media (for example: bad weather, sea water, etc.), the number of ballistic photons and serpentine photons is very small. Will be interrupted (bit error rate is too high)

Researchers have proposed a variety of ways to reduce these effects, including aperture averaging (AndrewsLC. J]. Optics communications. 2005, 248 (4): 359-374.), error correction coding (Chatzidiamantis ND, Karagiannidis GK, Uysal M. Generalized maximum-likelihood sequence detection for photon-counting freespace optical systems [J]. 3385.) and orbital angular momentum method (AlzubiJA, AlzubiOA, ChenTM. ForwardErrorCorrectionBasedOnAlgebraic-GeometricTheory[M]. Springer, 2014.), but these methods are mainly aimed at reducing the bit error rate for weak channel interference, and the implementation cost is high. It is not conducive to the practical application of wireless communication

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