This research puts forward a design regarding a novel compact bi-directional UWB (1.9–10.6 GHz) tapered slot patch antenna that has dual band-notches characteristics within 3.4–3.9 GHz applicable for WiMax application and 5-6 GHz applicable for WLAN (IEEE 802.11a and HIPERLAN/2 systems). A parasitic quasi-trapezoidal shape single split ring resonator SRR is positioned to secure the first WiMax band-notch to minimize the electromagnetic interference occurring in WiMax band. A single circular complementary split-ring resonator (CSRR) is etched to secure the second band-notch. Simulated and measured results showed a good match, thereby signifying that the proposed antenna is an optimum candidate for UWB communication applications along with the guide lines design to employ the notch bands in the preferred frequency regions.

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In future multi-hop wireless networks like 5G and B5G, efficient large-scale video sharing and data dissemination are expected to rely heavily on multicast routing and Cognitive Radio (CR) technology. While multicast routing is efficient when the network always has access to the spectrum, the dynamic nature of Primary User (PU) activities, heterogeneous spectrum across the CR Network (CRN), and PU access priority make it challenging to implement efficient multicast routing protocols in CRNs. This paper proposes a hierarchical multicast routing mechanism for multi-hop CRNs that exploits the Shortest Path Tree (SPT) and Minimum Spanning Tree (MST) concepts. The proposed multicast routing mechanism consists of tree construction and channel assignment algorithms. The tree-construction algorithm models the network topology as a multicast tree rooted at the CR source and spanning all the CR nodes. Based on the constructed tree, the channel assignment algorithm employs the Probability Of Success (POS) metric to assign channels to the various layers defined by the constructed SPT or MST, ensuring that the most reliable channel is used for the multi-hop multicast transmissions. Simulation experiments are conducted to evaluate the mechanism’s effectiveness, revealing significant improvements in throughput and Packet Delivery Rate (PDR) compared to state-of-the-art protocols under different network conditions. The simulations also show that the SPT-based mechanism outperforms the MST-based mechanism in terms of throughput but has a higher tree construction complexity.