# Low Power FPGA Implementation of a Smart Building Free Space Optical Communication System
Figure 1: Wireless Optical Communications Classifications. Data from Ref. [5]. FSO systems have a vast range of applications, such as outdoor wireless networks, LAN segmental small networks, optical fiber connections backup networks, backhauling, and military communications [13]. Unlike fiber-optical installations that despite being one of the most reliable networks have the most expensive cost, FSO is a much simpler network that requires only two optical transceivers for a full-duplex link, with the proper choice of optical source used to transmit the signal [14]. With the optimum kind of modulation depending on data rate needs and the type of territory the system is installed in, a fully-functioning low-cost communication spot is obtained [9; 10; 15; 16]. Apart from the competitive side, RF communications happen to require complementary FSO transceiver links that can reinforce the quality of service for remotely located users and increase the overall network capacity. Another example of outdoor FSO links is presented in [17]. To eliminate the direct LOS drawback of alignment and setup angle immobility problems multi-FSO transceivers can be tiled up to ensure the maximum spatial expansion and optimized performance for outdoor FSO links. Designing a high-rate and resource-efficient network infrastructure for 5G and beyond has received a lot of interest and turned into an extremely viral research topic. Another hybrid example is represented in [18], where Coexisting RF networks are integrated with optical-fiber networks and OWC systems to create an ultra-high coverage possibility for macro capacities that can handle the exponentially rising number of devices in the fifth generation evolution and IoT era. Neural networks and deep learning techniques were adaptively applied to rapidly detect the fault locations and optimize the performance of these hybrid networks. When it comes to prototyping methodically reciprocating systems and state-of-the-art alternatives, this is where system-on-chip (SOC) technology takes place. The vast need for executing multiple and highly diverting instructions calls for hugely integrated platforms specialized in various processing techniques and distinct architectures, including microcontrollers, digital signal processors, and reliable GPUs [19]. In recent years, the FPGA development pace has come up with a lot of chip families designers can pick from depending on the specifications required for the purposed application [19]. The key parameter of choosing the right processing aider is the milestone of the desired application. Compatibility of the processor used with the design specifications and future modification is crucial for picking the right tool. It is difficult to find the right hardware accelerator for a given application. There are many different types of digital signal processors (DSPs), FPGAs, and graphical processing units (GPUs), and the technical distinctions between them make it hard to compare them. Although they have different built-in architectures and software interfaces, they are capable of providing design platforms. The trade-offs between one type and another are the metric of comparison. Table 2 shows the pros and cons of using different processors.