## 1 Introduction
In FSO systems, focused and strong light beams are utilized to establish high-speed communication between two links, comprising distances from inter-chip to inter-satellite connections [16]. Studies [17; 18] have implemented an extremely fast pulse density modulation with extraordinarily effective spectrum characteristics by utilizing photodiodes. Multiple-input multiple-output (MIMO) techniques have been used as part of an advanced approach to enable high-speed data transmission across ultra-high-speed multi-channels [19; 20] in the context of the VLC and Li-Fi systems. As observed, systems using VLC, Li-Fi, and FSO technologies incorporate photodiodes as detectors, a choice that has some disadvantages, such as their suitability primarily for short-distance applications, increased susceptibility to the mobility effect, and challenges from outdoor environments, particularly when directing LED signals at photodiode receiver signals. With the OCC technique, an extended communication range of up to 200 m was demonstrated [21], which was achieved by using an image sensor instead of photodiodes. In a study conducted by [PERSON] et al. [22], the impact of different types of image sensors on an OCC system was discussed. In particular, the use of a global-shutter camera was investigated, revealing that the frame rate of the camera had an impact on the data rate of an OCC system, which is consistent with the principles of [PERSON]'s law. When using a rolling-shutter camera, in addition to the focal length and exposure duration of the camera, careful thought also should be given to the sampling rate, which depends on the rolling-shutter speed and the frame rate of the camera. The signal-to-noise ratio (SNR) becomes a crucial factor that requires consideration, particularly when sending data over long communication distances. Presently, Li-Fi technology is deployable within an outdoor environment, affording a communication range of 10 m through the utilization of a photodiode lens measuring 2 inches in diameter [23]. In the field of OCC techniques, the use of the MIMO technique has demonstrated effective operations and has successfully managed simultaneous connections involving both multiple light sources and cameras. However, it is noteworthy that the application of MIMO technology in the context of photodiodes faces limitations, making it infeasible to enable multiple connections. To address this limitation, the region of interest (RoI) signaling algorithm has emerged as a widely accepted approach capable of detectingmultiple light sources within the framework of an OCC system. In a study referenced as [24], a color intensity modulation MIMO scheme designed for data transmission by employing a global-shutter camera with a frame rate of 330 fps was introduced. Notably, owing to the use of color intensity modulation, the scheme is constrained to a maximum communication distance of 1.4 m, which is characterized by a high bit error rate (BER) of \(10^{-1}\). It is important to recognize that this scheme is only compatible with the relatively expensive and less prevalent global-shutter cameras. In addition, the use of colors as a means of data transmission in this scheme entails certain limitations, including a restricted communication distance and an increased BER compared to on-off keying (OOK) schemes. In another study, ref. [25], a MIMO technique based on an LED matrix coupled with a rolling-shutter mechanism was developed. Although this scheme successfully reduces flicker, it has some significant drawbacks. First, the communication range is only 1.4 m, and second, there is no rotational support. A rotational support is a crucial component that is required for implementing the OCC technique, which uses 2D codes in IoT systems. With a 2D codes scheme, the rotation support must be applied to ensure that the receiver side can decode the exact signal from the transmitter side with all camera angles.