## 1 Introduction
Fiber optics can guide light through a collimator, allowing signals to be transmitted over long distances in places without fiber optics, like space, land, and underwater [16; 17]. This helps simplify fiber-optic routing. As mentioned earlier, FSO systems can work with O-RAN technology in tests [18]. This shows that non-terrestrial networks are possible and highlights future applications. Previously, FSOs were often used as a backup for fiber optics [19]. However, to manage faster transmission, mobility, and lower maintenance costs, FSOs now play a key role [20; 21; 22], even though atmospheric turbulence, fog, bad weather, or building movement can disrupt it [23; 24; 25]. Solutions like power control, diversity techniques, beam steering, and adaptive modulation can help address these issues [26; 27; 28; 29]. Recent studies have shown that FSO communication can still be effective, even in tough weather conditions [30; 31]. Figure 1 illustrates the solution's primary goal: the server data center's network sent to the repeater building via the FSO link, overcoming the land barrier for use by the office network and beamforming application through the network switch. The mmW beamforming part is installed in the repeater building, mainly supporting the civic center and its outskirts to the suburban neighborhoods, such as household and shop networks. Where mmW beamforming is not effective, O-RAN RUs can be used as fronthaul terminals via fiber-optic links to supplement the coverage. Moreover, the RUs can be extended by fiber-optic links to reach farther distances, such as villages or remote locations where beamforming would be wasteful due to a small population. Historically, FSO communication has been integrated with radio frequency (RF) systems to enhance the capacity and coverage of traditional RF communication [32]. However, these integrations often entail limited beamforming capabilities and exclude O-RAN architectures. Furthermore, the RU antennas associated with O-RAN can be strategically positioned in alignment with network demands through the deployment of long-haul FSOs or optical fiber connections. This strategic placement contributes to improved coverage efficiency and optimizes overall cost-effectiveness. In this paper, it is emphasized that based on the 200 m FSO link as the backhaul and then processed by the O-RAN, it can undergo a fronthaul of up to 10 km to reach the RUs of the O-RAN and then through the customer premise equipment (CPE) or directly for users for 5G NR communication use. Conceptually, individual RUs of the O-RAN can be strategically positioned in the application area where mmW beamforming antennas cannot effectively cover, such as near the periphery of a sector. The 5G NR frequency band is n79. This exclusive frequency band can transmit data confidentially and is staggered from the proposed beamforming frequency of 28 GHz to avoid co-channel interference. Furthermore, mmW beamforming can optimize the phase of beamforming by RL with different beamforming steering angles for the best communication experience. Hence, conceptually, it is both cost-effective and feasible to complement the communication blindness of RL-based mmW beamforming with FSO link-based O-RAN RUs for future 5G/6G communication applications. The subsequent sections of this paper are organized as follows: Section 2 examines the architecture and experimental findings related to the incorporation of RL techniques into beamforming. Section 3 presents a discussion of the architectural considerations and experimental results concerning the application of FSOs within the context of the O-RAN system. Finally, Section 4 provides a conclusion to the paper.