# Location-Based Relay Selection in Full-Duplex Random Relay Networks
## 6 Conclusions  
We evaluated the performance of an FDRRN in terms of outage probability. We first derived the outage probability for the FDRRN and then identified the potential relay location that minimizes the outage probability. Based on these insights, we proposed a location-based relay selection scheme designed to reduce the selection complexity of FDRRNs. By demonstrating that the proposed algorithm can achieve performance comparable to that of the optimal solution, our work highlights the importance of considering location-dependent parameters, such as interference and path loss, in the design of efficient relay selection algorithms. Furthermore, this paper paves the way for several future works, including the investigation of multiple relay selection and selection diversity order in FDRRNs. Conceptualization, J.B. and T.K. ; methodology, J.B.; software, J.B.; validation, J.B. and T.K. ; formal analysis, J.B.; investigation, J.B. and T.K. ; visualization, J.B.; writing--original draft preparation, J.B.; writing--review and editing, T.K. ; funding acquisition, T.K. All authors have read and agreed to the published version of the manuscript. Figure 8: The achievable spectral efficiency of an FDRRN as a function of the density of the candidate relay nodes for the proposed, _max-min_, and optimal relay selection algorithms. Figure 7: The outage probability of an FDRRN as a function of the density of the candidate relay nodes for different SIR thresholds, \(\tau\). **Funding:** This work was supported by an Institute of Information Communications Technology Planning Evaluation (IITP) grant, funded by the Korean Government (MSIT) (No. RS-2024-00397789, Development and Standardization of 6G Radio Transmission Standard Technology). **Data Availability Statement:** The raw data supporting the conclusions of this article will be made available by the authors on request. **Conflicts of Interest:** Author [PERSON] was employed by the company SK Telecom Co., Ltd. The remaining authors declare that the re-search was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. * [PERSON] et al. (2023) [PERSON]; [PERSON]; [PERSON]; [PERSON]; [PERSON] Best relay selection strategy in cooperative spectrum sharing framework with mobile-based end user. _Appl. Sci._**2023**, _13_, 8127. [CrossRef]
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