# Handover Management for D2D Communication in 5G Networks
## 4 Proposed Approach
### Choosing Handover Target
However, it would introduce fewer handovers and achieve the best performance in terms of transmission latency and average throughput. ## 6 Conclusions

In this paper, we have proposed a novel handover mechanism for D2D communications. First, a list of handover candidate eNBs is generated for each D2D pair based on both DUEs' movements and received signal conditions. With the introduction of \(D_{counter}\) and the utility function, we can then determine the best handover target for this D2D pair. The decision jointly considers their historical movements and the received signal conditions. Second, we take into account both DUEs' satisfaction in terms of their received signal conditions with respect to their original and target serving eNBs to decide whether or not to hand over them to the target eNB simultaneously. As in the result, in addition to reducing handovers and decreasing transmission latency, the better performance in terms of received signal quality for both DUEs is also achieved. According to the simulation results, the proposed DTDP method shows better performance than the conventional standard and D-A3 method in terms of the total number of handovers, average utility value, and satisfied ratio, both at the system level and user level. Although the DP method, which does not account for \(D_{counter}\), shows better performance in the average utility value and satisfied ratio, it incurs more handovers and lengthens transmission latency, which leads to lower throughput. Figure 9: Total number of handovers, utility, and average satisfied ratio for the first D2D pair in the system versus its moving speed. (**a**) Total number of handovers for the first D2D pair. (**b**) Utility for the first D2D pair. (**c**) Average satisfied ratio for the first D2D pair. **Author Contributions:** Conceptualization, W.K.L. and F.-S.C.; software, F.-S.C. and M.-H.S. ; validation, C.-S.S.; writing--original draft preparation, C.-Y.H. and C.-S.S.; writing--review and editing, W.K.L. and C.-S.S.; supervision, W.K.L. All authors have read and agreed to the published version of the manuscript. **Funding:** This research was funded by MOST of Taiwan, under the grant number 108-2221-E-110-017-. **Conflicts of Interest:** The authors declare no conflict of interest. ## References

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