An enhanced security mechanism through blockchain for E-polling/counting process using IoT devices

Wireless Networks - One of the biggest challenges in political mayhem is visible during the election process where no stone is kept unturned in order to gain the power. Further, due to poll...     

Design of band-notched antenna with DG-CEBG

Ultra-wideband (UWB) disc monopole antenna with crescent shaped slot for double band-notched features is presented. Planned antenna discards worldwide interoperability for microwave access (WiMAX) band (3.3–3.6 GHz) and wireless local area network (WLAN) band (5–6 GHz). Defected ground compact electromagnetic band gap (DG-CEBG) designs are used to accomplish band notches in WiMAX and WLAN bands. Defected ground planes are utilised to achieve compactness in electromagnetic band gap (EBG) structures. The proposed WiMAX and WLAN DG-CEBG designs show a compactness of around 46% and 50%, respectively, over mushroom EBG structures. Parametric analyses of DG-CEBG design factors are carried out to control the notched frequencies. Stepwise notch transition from upper to lower frequencies is presented with incremental inductance augmentation. The proposed antenna is made-up on low-cost FR-4 substrate of complete extents as (42 × 50 × 1.6) mm³.Fabricated sample antenna shows excellent consistency in simulated and measured outcomes.     

Ultra-Wideband Compact Circularly Polarized Antenna

In this research work, a circularly polarized (CP) monopole antenna is designed for Ultra-Wideband (UWB) applications. The CP UWB antenna is be made up of a reformed ring patch and ground plane. The slots and stubs are inserted in the ground to achieve CP in the UWB antenna. This antenna attained an Axial Ratio Bandwidth (ARBW) of 5 GHz (4.0–9.0 GHz) that lies in the UWB frequency range that is from 3.1 to 10.6 GHz. The designed antenna has a radiation efficiency of around 80% for the complete UWB frequency range. The CP UWB antenna is designed and fabricated using the FR4 with a compact size of 32?×?30?×?1.6 mm³ and with a peak gain of 6.8 dBi. Tested results are in good resembles with simulated ones.

     

Design and Development of an Efficient EBG Structures Based Band Notched UWB Circular Monopole Antenna

Band notched circular monopole antennas for ultra-wide band applications are proposed in this paper. The proposed antennas in this paper can reject worldwide interoperability for microwave access WiMAX band (3.3–3.8 GHz) and wireless local area network WLAN band (5–6 GHz). Antennas utilises mushroom-type electromagnetic band gap (EBG) structures and I-slot embedded edge located via (ELV) EBG structures to achieve band-notched designs. The advantages of band notched designs using EBG structures like notch-frequency tuning, dual-notch antenna designs and stable radiation pattern are also verified. Various antenna designs with slot in EBG structures, variations in placement of EBG structures, number of EBG structures and ELV type EBG structures are simulated. About 30% reduction in size of EBG structures is obtained if conventional mushroom type EBG is replaced by proposed I-slot embedded ELV-EBG structure. Fabricated and measured results are in good agreement with simulated ones.

     

Scalable and Robust ANN Based Cooperative Spectrum Sensing for Cognitive Radio Networks

Cognitive radio network (CRN) supports dynamic spectrum access addressing spectrum scarcity issue experienced by today’s wireless communication network. Sensing is an important task and cooperative spectrum sensing is used for improving detection performance of spectrum. The sensing information from individual secondary users is sent to fusion center to infer a common global decision regarding primary user’s presence. Various fusion schemes for decision making are proposed in the literature but they lack scalability and robustness. We have introduced artificial neural network (ANN) at fusion center thereby achieving significant improvement in detection performance and reduction in false alarm rate as compared to conventional schemes. The proposed ANN scheme is found capable to deal with scalability of CRN with consistent performance. Further, SNR of individual Secondary user is taken into consideration in decision making at fusion center. Moreover the proposed scheme is tested against security attack (malicious users) and inadvertent errors occurring at SUs are found to be robust.