# Inter-Beam Co-Channel Downlink and Uplink Interference for 5G New Radio in mm-Wave Bands +
## 6 Conclusions  
This paper is devoted to assessing the limitations that exist in multi-beam antenna systems. Here, the SIR is the primary metric that is used to evaluate the level of interference between the intra-cell beams. The presented procedure for assessing this parameter is based on the PAS analysis, which is determined by simulation tests. By using the channel transmission characteristics (i.e., TDL or PDP) to create the geometric MPM structure, the results of assessing the received power are closely related to the different propagation environment type. Using the MPM allows mapping the impact of the antenna beam radiation patterns on the PAS. The presented methodology allows evaluating changes in the PAS as a function of antenna beam shape and parameters such as the maximum radiation direction, main and side-lobes beamwidths. Additionally, the ability to evaluate the SIR under both LOS and NLOS conditions justifies using this method in the network planning process of energy and spectral management of 5G system with the multi-beam antenna systems. In the multipath propagation environment, in most cases to evaluate fluctuations in the received signal level, the Rician and Rayleigh distributions are used for LOS and NLOS conditions, respectively. The SIR assessment is the basis for determining the parameters of these characteristics. Due to the association of the SIR with the propagation properties of the environment, it is justified to use the presented SIR assessment methodology in the 5G network planning. The ability to adapt the developed model to any environment, weather conditions, and multi-beam antenna system distinguishes this SIR determination method from among the methods used so far. The comparison of the mean results for the proposed methodology with a similar approach based on the 3 GPP statistical model shows that the same optimal directions for the adjacent gNodeB beams might be determined faster based on the MPM approach. A more detailed comparison of the two solutions with regard to the interference level assessment in the 3.5 GHz band will be presented in the authors' next work [49]. In the future, we also plan to conduct empirical research for selected scenarios that will allow us to verify the approach presented in this paper.  
Conceptualization, J.M.K. and C.Z.; methodology, K.B., J.M.K., and C.Z.; software, K.B. and J.M.K.; validation, K.B. and J.M.K.; formal analysis, C.Z.; investigation, K.B. and J.M.K.; resources, K.B. and J.M.K.; data curation, K.B. and J.M.K.; writing--original draft preparation, K.B., J.M.K., C.Z., and L.N.; writing--review and editing, K.B., J.M.K., C.Z., and L.N.; visualization, J.M.K.; supervision, C.Z.; project administration, J.M.K. and C.Z.; funding acquisition, J.M.K. All authors have read and agreed to the published version of the manuscript.  
**Funding:** This research was funded by the POLISH MINISTRY OF DEFENSE, grant number GBMON/13-996/2018/WAT on \"Basic research in sensor technology field using innovative data processing methods\" and grant number UGB/22-730/2020/WAT on \"Impact of various propagation conditions on effectiveness of wireless communication and electronic warfare systems\".  
**Institutional Review Board Statement:** Not applicable.  
**Informed Consent Statement:** Not applicable.  
**Data Availability Statement:** The data presented in this study are available on request from the corresponding author. The data are not publicly available due to project restrictions.  
**Acknowledgments:** The authors would like to express their great appreciation to the _Sensors_ journal Editors and anonymous Reviewers for their valuable suggestions, which have improved the manuscript quality.  
**Conflicts of Interest:** The authors declare no conflict of interest.