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In a heterogeneous wireless network, handover techniques are designed to facilitate anywhere/anytime service continuity for mobile users. Consistent best-possible access to a network with widely varying network characteristics requires seamless mobility management techniques. Hence, the vertical handover process imposes important technical challenges. Handover decisions are triggered for continuous connectivity of mobile terminals. However, bad network selection and overload conditions in the chosen network can cause fallout in the form of handover failure. In order to maintain the required Quality of Service during the handover process, decision algorithms should incorporate intelligent techniques. In this paper, a new and efficient vertical handover mechanism is implemented using a dynamic programming method from the operation research discipline. This dynamic programming approach, which is integrated with the Technique to Order Preference by Similarity to Ideal Solution (TOPSIS) method, provides the mobile user with the best handover decisions. Moreover, in this proposed handover algorithm a deterministic approach which divides the network into zones is incorporated into the network server in order to derive an optimal solution. The study revealed that this method is found to achieve better performance and QoS support to users and greatly reduce the handover failures when compared to the traditional TOPSIS method. The decision arrived at the zone gateway using this operational research analytical method (known as the dynamic programming knapsack approach together with Technique to Order Preference by Similarity to Ideal Solution) yields remarkably better results in terms of the network performance measures such as throughput and delay.

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Summary This study presents the design of a multiband monopole antenna using the metamaterial (MTM) loading technique for embedded automotive Internet‐of‐Things (IoT) communications. The proposed antenna consists of a simple microstrip line monopole loaded with a novel E‐slotted MTM. The unit cell MTM consists of a central transmission line loaded with parasitic patches that are deployed with “E”‐shaped slots. The MTM is symmetrically loaded to either side of the monopole antenna to achieve miniaturization through frequency reduction and to realize multiple resonances. The proposed monopole antenna has a footprint of 10 × 30 mm2 and operates at 2.45, 3.3, and 3.8 GHz suitable for Industrial Scientific and Medical applications (ISM), Wireless Fidelity (WiFi), and Worldwide Interoperability for Microwave Access (WiMAX) applications that are exploited in IoT communications. The prototype antenna is fabricated, and the simulation results are validated using experimental measurements. The prototype antenna offers the measured impedance bandwidth of 6%, 7%, and 10% at the said frequencies. The measured gain of the antenna is greater than 3.2 dBi, and the simulated efficiency is close to 86% throughout the operating bandwidth. The performance of the proposed antenna in the vicinity of the vehicle is tested, and the results are presented.

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