Optical MIMO Communication Based on Joint Control of Base Station and OPA-Type OIRS

As a new type of optical communication device, the optical intelligent reflecting surface (OIRS) can reflect, shape and split optical signals in real time, and is expected to expand the application scenarios of optical wireless communication. However, in the existing research, a single OIRS cannot support optical multiple input multiple output (MIMO) communication since OIRS performs the same modulation on all incident light. In this article, we propose an optical MIMO communication system based on joint control of base station and optical phased array (OPA)-type OIRS. The communication system utilizes the OPA-type OIRS's characteristic of superimposing the input optical phase and the OIRS's phase to implement a joint beam control scheme of the base station and the OIRS, thereby realizing optical MIMO communication with a single OIRS. Considering the OIRS's physical model, pointing error, atmospheric turbulence and attenuation, our work establishes the mathematical model of the optical MIMO communication system, and derives the closed-form expression of the probability density function (PDF) of the channel fading, asymptotic outage probability and bit error rate (BER) for the first time. Experiments and simulations are built to verify the feasibility and accuracy of our system model and theoretical derivation, which proves that our results are consistent with the actual system.