This paper addresses cochannel interference (CCI) in mobile networks. So enhancements of network performance by decreasing CCI are assessed using four diverse interference reduction techniques. These techniques signify traditional sectored fractional frequency reuse (FFR), sectored FFR with beamforming (BF), relay‐assisted (R‐A) sectored FFR, and R‐A sectored FFR with BF technique. Additionally, each BF cooperative technique applies the vertical BF, three‐dimensional (3D) BF, and horizontal BF. Consequently, sectored FFR with BF contains three cases. These cases indicate sectored FFR applies horizontal BF, sectored FFR deploys vertical BF, and sectored FFR uses 3D BF. Furthermore, there are three different arrangements of applying BF in R‐A sectored FFR with BF. These arrangements signify that relay station (RS) employs BF only, base station (BS) uses BF only, and both RS and BS apply BF. Therefore, each arrangement consists of three different cases according to the applied BF technique. Consequently, nine dissimilar cases are considered. Also, a comparison of all cases in different techniques is introduced to enhance the network performance. Analytical treatments are conducted. As a result, closed‐form expressions (CFEs) for worst cases cell‐center user's (CCU's) signal‐to‐interference ratio (SIR), cell‐edge user's (CEU's) SIR, and inner radius (IR) are implemented. These closed forms are used to complete the comparison of all techniques using numerous performance evaluation metrics. The results show, that as unpredicted, the performance of R‐A sectored FFR is close to that of R‐A sectored FFR BF in low SIR threshold and high path‐loss exponent (PLE) ranges. Therefore, R‐A sectored FFR is preferred to be used from the perspectives of network cost and power consumption. Furthermore, vertical BF shows performance close to that of 3D BF in low PLE range. Consequently, using vertical BF is preferable with regard to the energy preservation and network budget. Moreover, it is noticed that BS that applies BF arrangement outperforms other arrangements when vertical or horizontal BF technique is applied. Additionally, the arrangement of both RS and BS that apply BF is superior to the other arrangements when 3D BF is used. But, as expected, it does worse than the others if the other BF techniques are applied. The work results achieve much higher CEU SIR enhancement. Therefore, the probability of outage is decreased. Then, rate of served users by the network is heightened. Accordingly, the total network cost is reduced. So this study advances the network performance while maintaining lower network cost.

中文翻译：

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不同协作蜂窝网络的分析与比较

本文讨论了移动网络中的同信道干扰（CCI）。因此，使用四种不同的干扰减少技术来评估通过降低CCI来增强网络性能。这些技术表示传统的扇形分数频率复用（FFR），带波束成形的扇形FFR（BF），中继辅助（R‐A）扇形FFR和带BF技术的R‐A扇形FFR。此外，每种BF合作技术都应用垂直BF，三维（3D）BF和水平BF。因此，带有BF的扇形FFR包含三种情况。这些情况表明扇形FFR应用水平BF，扇形FFR部署垂直BF，扇形FFR使用3D BF。此外，在带有BF的R-A扇区FFR中有三种不同的应用BF的安排。这些安排表示中继站（RS）仅使用BF，基站（BS）仅使用BF，而RS和BS均使用BF。因此，根据所应用的BF技术，每种排列都包括三种不同的情况。因此，考虑了九种不同的情况。此外，还引入了对不同技术中所有情况的比较，以增强网络性能。进行分析处理。结果，实现了针对最坏情况的像元中心用户（CCU）信号干扰比（SIR），像元边缘用户（CEU）SIR和内半径（IR）的闭式表达式（CFE）。这些封闭的表格用于使用众多性能评估指标来完成所有技术的比较。结果表明，出乎意料的是，在低SIR阈值和高路径损耗指数（PLE）范围内，R-A扇区FFR的性能接近R-A扇区FFR BF。因此，从网络成本和功耗的角度来看，最好使用R-A扇区FFR。此外，垂直BF在低PLE范围内的性能接近3D BF。因此，就节能和电网预算而言，最好使用垂直BF。此外，注意到，当应用垂直或水平BF技术时，应用BF布置的BS优于其他布置。另外，当使用3D BF时，应用BF的RS和BS两者的布置都优于其他布置。但是，正如预期的那样，如果应用其他高炉技术，效果会比其他方法差。工作结果实现了更高的CEU SIR增强。因此，减少了停机的可能性。然后，提高了网络服务用户的比率。因此，降低了总网络成本。因此，本研究在保持较低网络成本的同时提高了网络性能。