基于MIMO-OFDM的室内可见光通信降噪研究

Research on noise reduction of indoor visible light communication based on MIMO-OFDM

解决阴影效应和多径效应一直是研究可见光通信系统的关键。提出利用MIMO(Multi Input Multi Output)技术扩大通信过程中信号传输的信道容量,配合LED的高强度光线,实现室内光照的大面积覆盖和抗阴影能力。而OFDM(Orthogonal Frequency Division Multiplexing)的调制方式,它的循环前缀能够解决光信号在室内传播过程中引起的多径效应,降低码间干扰的强度,并提高频谱利用率,解决了LED芯片可调制宽带不足的问题。与传统的室内光通信相比,提出利用MIMO-OFDM的编码方式能够提高可见光通信系统在室内的通信水平,并且在保证光照强度的同时实现信号的高信噪比传输。

Solving the shadow effect and multipath effect has always been the key to the study of visible light communication systems. This paper proposes to use MIMO(Multi Input Multi Output) technology to expand the channel capacity of signal transmission in the communication process, and to cooperate with the high-intensity light of LED to achieve large-area coverage of indoor lighting and anti-shadow ability. The OFDM(Orthogonal Frequency Division Multiplexing) modulation method, its cyclic prefix can solve the multipath effect caused by the optical signal in the indoor propagation process, reduce the intensity of inter-symbol interference, and improve the spectrum utilization rate, which solves the problem that the LED chip can be modulated The problem of insufficient broadband. Compared with the traditional indoor optical communication, this paper proposes that the use of MIMO-OFDM coding method can improve the indoor communication level of the visible light communication system, and realize the high signal-to-noise ratio transmission of the signal while ensuring the light intensity.