<span class="s22">In this paper, we proposed a hexagonal shaped </span><span class="s22">microstrip</span><span class="s22"> ultra-wideband (UWB) antenna integrated with dual band applications. The antenna design consists of a hexagonal shape patch with two folded Capacitive Loaded Line Resonators (CLLRs) on the left edge of the patch antenna. This hexagonal structure is used to implement UWB applications (3.1-10.6 GHz). A rectangular ground</span><span class="s22">,</span><span class="s22"> and two CLLR are also used on t</span><span class="s22">he bottom of antenna to obtain</span><span class="s22"> the extra dual resonant frequency at 2.4 GHz and 9.1 GHz for </span><span class="s22">B</span><span class="s22">luetooth and radar applications respectively. The proposed design is implemented using FR4 epoxy substrate. The relative permittivity of the substrate is 4</span><span class="s22">.4. The overall size of designing</span><span class="s22"> antenna is 26 × 30 mm2 with 1.6 mm as thickness and fed by standard feed line of 50 Ω </span><span class="s22">microstrip</span><span class="s22">. The results obtained from the simulation indicate that the designed antenna attains a good bandwidth from 1.1 GHz – 10.69 GHz with VSWR &lt; 2 and return loss &lt; -10 </span><span class="s22">dB.</span><span class="s22"> The proposed geometry is s</span><span class="s22">imulated  by using the </span><span class="s22">Ansoft</span><span class="s22"> HFSS </span><span class="s22">simulator working on the principle of FEM and results are also analyzed.</span>

With increasing transmission of sensitive information over the dispersed IoTs, security of sensitive patient’s contents is becoming more challenging and has been enthusiastic area of research since last decades. Evolution in the concealment of data was reflected in the medical field specifically on medical images. Hide information technology in the image is called steganography. The objective of this study is the preservation of privacy and confidentiality of data in uncertain surroundings during multimedia exchange joining two IoT hops. For attacker hindrance and, provision of data confidentiality, a resilient multilevel security perspective depending on information hiding and cryptography is suggested. The existing schemes have limitations related to the equilibrium trade-off amid two variables (medical image quality and security). In addition, the direct embedment of the secret data into the images and further subtraction of an encrypted data from it often enables the intruders to easily detect and extract the hidden information. Based on these factors, we proposed a multilevel security based on 3 th random iterations with chosen a procedure was implemented using Henon function to stop against cybercrimes challenges. The patient information is going through the preparation stage (different steps) before the embedding algorithm in order to increase the security. Superior results achieved with this study in term of imperceptibility and security the reason is to choose the right method in the right place. Satisfying results, gained when benchmarking our results with existing one in literature through the same criteria.

Wireless Fidelity (Wi-Fi) network is created on the IEEE 802.11 standard. Connections for local devices in homes and business arenas are provided by Wi-Fi units. With the growing demand as well as penetration of wireless services, the wireless networks users now assume Quality of Service (QoS) besides performances comparable to what is accessible from secure networks. In this paper, OPNET Modeler is used as module and for the simulation of a fiber optic-based Wi-Fi network within a fixed local area network. The aim of this paper is to evaluate their Quality of service (QoS) performances in terms of Wi-Fi voice-packet delay and End-to-End for both Wi-Fi base fiber and Wi-Fi base line. Many scenarios, with same Physical and MAC parameters, have many subnet networks are implementing with fiber optics baseline in addition to Wi-Fi baseline, were created in the network OPNET simulation tool for obtaining the results. The results of simulation reveal that base line demonstrated more delay than base fiber.

The use of optical-OFDM systems is mainly restricted by their limited dynamic range as a result of a high peak to average power ratio (PAPR) and nonlinear distortion (NLD). Radio-over-Fiber (RoF) systems are mainly deployed for light modulation and mm-wave signals transmission over fiber links. This paper evaluated the performance of RoF links with respect to their external modulation in a bid to highlight the challenges attributable to the various optical system components. The Mach-Zehnder Modulator (MZM) have been used in external modulation; it is a tested modulation scheme for quadrature amplitude modulation QAM (a vector modulation format) where signal subcarriers are generated using an OFDM scheme. Simulation results based on Optisystem 13 software exposes that the receiver performance of the optimum system for achieving has a better Bit Error Rate (BER) and three longest distance as 10, 50, 100 km for 16 QAM-OFDM-RoF system are reached by using optimum receiver launch power.

Partial discharge (PD) is a major problem in high voltage (HV) insulation that it can lead to electrical degradation and ultimate failure of the insulation materials. Recent research found that with the use of nanoparticles, the correct combination of nanofiller with resin will enhance the electrical, mechanical and thermal properties of HV insulation. Boron nitride (BN) is a ceramic dielectric material, with high electrical breakdown strength and high thermal conductivity. This research investigated the effects of BN nanofiller on the PD characteristics of epoxy resin, using CIGRE Method II electrode configuration. The PD number, PD charge magnitude, and average of PD charge during the ageing time under HV stress were investigated. Moreover, the degraded surfaces of the tested samples were examined using optical microscopy techniques before and after PD stress. The results revealed that higher BN nanofiller percentage will decrease the PD magnitude, PD number and the PD charge. As a consequence, the degraded area caused by the PD activities decreases as the amount of the BN nanofiller increases.