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The detection and characterisation of electromagnetic signals within a specific frequency range, known as spectrum sensing, plays a crucial role in Cognitive Radio Networks (CRNs). The CRNs aim to adapt their communication parameters to the surrounding radio environment, thereby improving the efficiency and utilisation of the available radio spectrum. Spectrum sensing is particularly important in device‐to‐device (D2D) communication when operating independently of the cellular network infrastructure. The Medium Access Control (MAC) protocol coordinates device communication and ensures interference‐free operation of the CRN coexisting with the primary cellular network. A spectrum sensing strategy at the MAC layer for cognitive D2D communication. The strategy focuses on reducing the overall sensing period allocated at the MAC layer by having each Cognitive D2D User (cD2DU) sense a smaller subset of available channels while maintaining the same sensing time for cellular user detection at the physical layer. To achieve this, the concept of concurrent groups of D2D devices is introduced in proximity, which are formed by using unique IDs of cD2DUs during the device discovery stage. Each concurrent group senses a specific portion of the cellular user band in a shorter time, resulting in a reduced overall sensing period. In addition to mitigating traffic congestion through data diversion from the cellular network, the proposed strategy facilitates the concurrent sensing of multiple channels by cD2DUs within the underutilised cellular user band. This leads to extended data transmission periods, increased network throughput, and effective offloading of the cellular network. The effectiveness of the proposed work is evaluated by considering factors, such as network throughput and transmission time. Simulation results confirm the effectiveness of the approach in improving spectrum utilisation and communication efficiency in multi‐channel Cognitive D2D Networks (cD2DNs). The focus is on spectrum sensing within Cognitive Radio Networks (CRNs) and its significance in device‐to‐device (D2D) communication. The authors present a novel spectrum sensing strategy at the Medium Access Control (MAC) layer specifically tailored for cognitive D2D communication. This strategy introduces the concept of concurrent groups, formed by unique IDs of cognitive D2D users, to reduce the overall sensing period in the cellular user band. By implementing this approach, the authors aim to enable simultaneous sensing of multiple channels by cognitive D2D users, leading to increased data transmission time and enhanced network throughput. The effectiveness of the proposed method is evaluated through simulations, demonstrating its potential in improving spectrum utilisation and communication efficiency in multi‐channel Cognitive D2D Networks (cD2DNs).

Heterogeneous networks (HetNets) refer to the communication network, consisting of different types of nodes connected through communication networks deploying diverse radio access technologies like LTE, Wi‐Fi, Zigbee, and Z‐wave, and using different communication protocols and operating frequencies. Vertical handover, is the process of switching a mobile device from one network type to another, such as from a cellular network to a Wi‐Fi network, and is critical for ensuring a seamless user experience and optimal network performance, within the handover process handover triggering estimation is one of the crucial step affecting the overall performance. A mathematical analysis is presented for the handover triggering estimation. The performance evaluation shows significant improvement in the probability of successful handover using the proposed handover triggering condition based on speed, distance, and different mobility models. The handover triggering condition is optimised based on the speed of the mobile node, handover completion time, and the coverage range of the current and the target networks of the HetNet node, with due consideration of the mobility model. Vertical handover, is the process of switching a mobile device from one network type to another, such as from a cellular network to a Wi‐Fi network, and is critical for ensuring a seamless user experience and optimal network performance, within the handover process handover triggering estimation is one of the crucial step affecting the overall performance. A mathematical analysis is presented for the handover triggering estimation. The handover triggering condition is optimised based on the speed of the mobile node, handover completion time, and the coverage range of the current and the target networks of the HetNet node, with due consideration of the mobility model.

The integration of cognitive radio and device-to-device (D2D) communication gives rise to Cognitive D2D (cD2D) communication, which offers numerous advantages, such as improved spectrum and energy efficiency, increased network throughput, and enhanced coverage. Although there are existing survey papers on cognitive networks and D2D communications, the topic of integrated cD2D communication has received limited attention. To bridge this gap in the literature, this paper presents a comprehensive survey of cD2D communication. We commence by introducing cD2D communication and highlighting the key research challenges in this field. Subsequently, we categorize the recent advancements in cD2D communications into eight major types of techniques and provide an in-depth review of the existing literature. Furthermore, we address several significant challenges associated with cD2D communications and discuss future applications that can benefit from this technology. Through our analysis, we aim to contribute to a deeper understanding of cD2D communication and provide insights into its potential for various domains.

: Improving our understanding of the association between medication errors and health information technology (health IT) usability has the potential to reduce errors and improve patient safety. We utilized patient safety event reports (PSEs) to investigate the contribution of usability challenges associated with the electronic medication administration record (eMAR) to medication errors.