# Interference Challenges and Management in B5G Network Design: A Comprehensive Review
## 4 Interference in B5G Networks
### Device-to-Device (D2D)
#### 4.2.5 Related Work in D2D  
Power allocation strategies  
In [98], the side-lobe interference reduced vertex coloring (SIRVC) algorithm-based resource allocation for concurrent mm-wave D2D transmission was proposed. The resource allocation decreases interference and enhances the throughput by scheduling all the flows in a minimum number of time slots. The proposed algorithm was compared with the conventional vertex coloring (VC) algorithm and the time division multiple access (TDMA) method under the same condition. It was noted that the proposed algorithm outperforms conventional TDMA and conventional VC algorithms. The simulation results stated that the throughput per time slot of the proposed algorithm improved significantly by around 12.5%. Moreover, the interference due to the side-lobe was found to have an evident bad effect on the performance of the network. Furthermore, the results indicated that the throughput per time slot increases if the side-lobe interference is controlled by choosing an appropriate threshold. Nonetheless, the impact of the ICI, which affects the system throughput, was not considered in this study. In [99], the authors proposed a model integrating a Gaussian directional antenna with a two-ray channel, creating an mm-wave D2D network that minimizes transmission power according to device allocation and beamwidth selection. A distributed structure is used to associate these devices while also utilizing the particle swarm optimization (PSO) technique to determine the most effective beamwidth to transmit and/or receive. Simulation results stated that, in comparison to existing interference management scenarios that disregard devices' transmission power, the proposed scenario was able to efficiently minimize transmission power and interference as well as maximize the sum rate of the system resulting in better performance. Nevertheless, the different heights of transmitters that have a large influence on the D2D power optimization were not taken into consideration. In [100], the interference management (IM) and RA problems of D2D communications underlying HetNet was investigated. To minimize the interference and dead-zone obstacles, the downlink/uplink decoupling user association (DL/UL-DUA) procedure was considered which quantifies its ability on IM and network-wide D2D performance improvements. UL fractional frequency reuse (FFR) schemes adaptively determine where the sub-band-bandwidths (SB-BWs) are located depending on the density of UE, the density of e-node-B (eNB), and the on/off switching frequencies of the SCs. The simulation results showed that the proposed scenario considerably minimizes the number of CUEs in an outage. The CBM gave an accurate performance to the comprehensive solution with significantly decreased running time. Nevertheless, the impact of intra-cell interference was ignored in centralized systems since it was assumed that eNBs distribute RBs of an allocated SB orthogonally. This causes system throughput degradation. Spectrum allocation strategies  
In [2], a new PPP technique that depends on stochastic geometry to model the SINR, ergodic capacity, outage probability, and probability of success for the D2D-enabled cooperative cellular network was implemented. The proposed technique included a wide variety of interference by considering a multiple-hope high-density D2D-enabled cooperative cellular network in which the signal is conveyed from the BS to D2D bypassing three network hops: BS to RN, an RN to a CU, and CU to D2D user (DU). In addition, the FD mode and decode-and-forward (DF) protocol were utilized by RNs. Finally, the performance of the proposed approach was compared with the grid model and traditional multi-antenna ultra-dense network (MA-UDN) approaches. The simulation results stated that the proposed approach outperforms the grid model and traditional multi-antenna ultra-dense network (MA-UDN) approaches.