In order to address the exponential growth of data traffic, the concept of device-to-device (D2D) communication has been introduced in fifth generation (5G). The seamless handover to the finest available access network is very essential in furnishing high quality of experience (QoE) to the devices involved in D2D communication. An intelligent, fast and reliable vertical handover (VHO) decision scheme is required for D2D to achieve seamless mobility and uninterrupted service. To address these issues, a two-stage fuzzy logic-based VHO scheme is proposed in this work. Here, fuzzy logic-based handover requirement analysis (HRA) is carried out in stage 1 based on received signal strength (RSS), data rate (DR) and latency (LA). This stage minimizes the unnecessary handovers. In stage 2, fuzzy-analytic hierarchy process (Fuzzy-AHP), fuzzy-technique for order preference by similarity to ideal solutions (Fuzzy-TOPSIS) are used in ranking and selecting the target access network. Through simulations, it has been proved that the proposed scheme offers improved performance than the classical and fuzzy-based multi-attribute decision-making (MADM) schemes. The proposed scheme offers 3.45$\%$, 7.33$\%$, 13.51$\%$, 40$\%$ minimum improvement in data rate, handover decision delay, handover blocking probability and number of handovers executed over the classical MADM schemes considered.

为了解决数据流量的指数增长，第五代（5G）中引入了设备到设备（D2D）通信的概念。无缝切换到最好的可用接入网络对于为D2D通信中涉及的设备提供高质量的体验（QoE）至关重要。D2D需要一种智能，快速且可靠的垂直切换（VHO）决策方案，以实现无缝的移动性和不间断的服务。为了解决这些问题，本文提出了一种基于模糊逻辑的两阶段VHO方案。在此，基于接收信号强度（RSS），数据速率（DR）和等待时间（LA）在阶段1中执行基于模糊逻辑的切换要求分析（HRA）。此阶段将不必要的切换减到最少。在第2阶段，模糊分析层次过程（Fuzzy-AHP），通过与理想解决方案（Fuzzy-TOPSIS）相似的顺序偏好的模糊技术被用于对目标访问网络进行排名和选择。通过仿真，证明了该方案比经典的和基于模糊的多属性决策（MADM）方案具有更高的性能。拟议方案提供3.45$％$，7.33$％$，13.51$％$，40$％$ 在考虑的经典MADM方案上，数据速率，切换决策延迟，切换阻塞概率和执行的切换次数的最小改进。