A multi-user transmission precoding design method in visible light communication

Abstract

The invention discloses a multi-user sending precoding design method in visible light communication, and belongs to the field of wireless optical communication. According to the method, the nonlinearity and illumination requirements of the LED are comprehensively considered, and a multi-user sending precoding algorithm under optical constraint is established, so that multi-user interference can besuppressed while the expected indoor illumination level is kept, and the method is more suitable for being applied to a multi-user visible light communication system. According to the method, optimalsending precoding conforming to actual constraints is formulated, the purpose of maximizing the minimum signal-to-interference-plus-noise ratio between users is achieved, and compared with a traditional zero-forcing algorithm based on pseudo-inverse, the method has obvious performance gain; furthermore, due to the fact that the multi-user precoding sending design problem in visible light communication is quasi-convex, the optimal solution of the precoding sending matrix can be effectively obtained through the dichotomy, meanwhile, the direct current bias voltage needed by the expected dimminglevel is obtained, and the dimming control function is achieved.

Description

Technical field [0001] The invention relates to a multi-user transmission precoding design method in visible light communication, and belongs to the field of wireless optical communication. Background technique [0002] LED-based visible light communication can operate in an unlicensed spectrum, and has the advantages of high-level information security, low cost, and high data rate, so it has become the research direction of many scholars at home and abroad. The use of visible light communication can not only realize functions such as data broadcasting, indoor positioning and intelligent traffic control, but also suitable for wireless transmission in special environments such as underwater and inside aircraft. Compared with traditional communication, it has higher directivity and confidentiality. Sex. [0003] In LED visible light communication, installing multiple LED sources can not only provide sufficient lighting to the outside world, but also provide wireless services to mult...

AI Technical Summary

Problems solved by technology

When using a general modulation with a non-zero mean, it will lead to complex optical power constraints and a design objective function that is more difficult to handle than the special case of zero-mean modulation; so in order to solve the problem of LED visible light communication, it is necessary to ensure the level of illumination while mitigating many Mutual interference between users, the present invention proposes a multi-user transmission precoding design method in visible light communication and its application

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