# Interference Mitigation Strategies in Beyond 5G Wireless Systems: A Review
## 1 Introduction
B5G is expected to increase traffic capacity and network quality by 100\(\times\)[29]. In the 35 GHz ultra-high frequency band, technology can transmit data at a speed greater than 1 Gbps, and the longest transmission distance can be around 2 km. Compared to 4G, B5G has thousands of times higher mobile data and 10 to 100 times the number of connected devices. Moreover, it has more battery power, and lower latency [30; 31]. By employing emerging technologies such as SCs, mm-Wave, and massive multiple-input multiple-output (m-MIMO), it is expected that B5G cellular networks accommodate network load (NL) increment. Capacity gain can also be accomplished by the use of device-to-device (D2D) communication with spatial and frequency reuse (FR) [32; 33; 34]. There are many challenges in implementing B5G networks including security and privacy management, channel access control management, load balancing (LB), quality of service (QoS) management, handoff management, and interference management (IM) [35; 36; 37]. Among these challenges, IM is particularly critical due to the high user density, FR, and heterogeneous architecture of B5G networks. Interference degrades signal quality, reduces network capacity, and negatively impacts QoS. To maintain reliable and efficient communication, it is essential to understand the sources of interference and apply mitigation strategies tailored to different B5G components. \begin{table}
\begin{tabular}{c c c c} \hline \hline
**Network Type** & \begin{tabular}{c} **Theoretical** \\ **Download Speeds** \\ \end{tabular} & \
\begin{tabular}{c} **Average Download** \\ **Speeds** \\ \end{tabular} &
\begin{tabular}{c} **Peak Download** \\ **Speeds** \\ \end{tabular} \\ \hline B5G & 50–100+ Gb/s & \(\sim\)1–5 Gb/s & 10–20 Gb/s \\
5G & 10–50 Gb/s & 130–240 Mb/s & 599 Mb/s \\
4G & 300 Mb/s & 32.5 Mb/s & 90 Mb/s \\
3G & 42 Mb/s & 8 Mb/s & \(\sim\)20 Mb/s \\ \hline \hline \end{tabular}
\end{table} 
Table 1: Data speeds for 3G, 4G, and B5G. Although the B5G network architecture includes emerging components such as satellite communication and unmanned aerial vehicle (UAV) systems, this review primarily focuses on IM within traditional terrestrial B5G structures, including D2D, HetNets, inter-cell interference (ICI), and artificial intelligence (AI)-based frameworks. which are widely deployed and standardized by third-generation partnership project (3 GPP). Information theory seeks to describe the ability of any wireless network, i.e., the maximum possible collection of rates for effective communication [38]. The research community has turned its focus towards interference-limited networks, starting from the capability characterization of noise-limited networks. Interference is known to be the final contact barrier that has to be resolved [39]. Figure 2, shows a detailed view of possible sources of interference in a B5G cellular network, including satellites, aircraft, and ground-based elements that connect through different communication links [1]. In the B5G network, there are two kinds of interference; ICI that takes place between different cells, such as micro-cells and SCs. Here, mitigation of the interference requires using some techniques like coordinated multipoint (CoMP), power control (POC), and scheduling to ensure communications link performance. Another type is called intra-cell interference which takes place between devices within the same cell. Minimizing this type of interference is done using orthogonal resource allocation (RA) for data transmission [40; 41; 42]. In multi-tier and heterogeneous B5G cellular networks, the management of radio resources and interference would be a key research issue. In this context, conventional IM and radio resource strategies such as LB, POC, and channel allocation may not be successful  
Figure 2: Layered architecture of potential interference sources in a B5G network, including satellite, airborne, and terrestrial components. and a new look at the problem of IM will be needed.