This research presents patch antenna design that enhances its performance to work in 5G band with: sufficient bandwidth, acceptable insertion loss level and effective gain value. A selective procedure for finding suitable patch height has been undertaken. Parallel to this a technique of inserting appropriate Rectangular back holes in substrate has been also made. A simulation program using recent version of the well-known HFSS has been used for obtaining best of results. Sufficient bandwidth values in the range of (27 - 29.39)GHz with return loss range( -15dB - -33dB) have been obtained with acceptable gain value.

The security of the communication channels has become a hot research topic for the 5G due to the tremendous advancements in wireless communications over the past two decades, including the recent emergence of the fifth generation (5G) in mobile wireless communications, which is anticipated to support extremely large user connections and exponentially increase the wireless services. This paper describes a new approach to the problem of interception of wireless communication channels between the legitimate users. Physical Layer Security PLS is new topic enhancing the secrecy performance of a Single-input-multiple-output (SIMO) system for wireless communication from one base-station equipped by single transmitting antenna to many users equipped by multiple receiving antennas each. The receiving beamforming techniques “with a perfect channel CSI is assumed”, such as Maximum Ratio Combining MRC and Equal Gain Combining EGC is utilized in order to achieve the perfect secure receiving for the legitimate users. A downlink transmission of Multiple-input-Single-output (MISO) has been designed ‘Basestation’ equipped by multiple transmitting antennas and users (legitimate and Eavesdropper) with single receiving antenna can focus the information signal in the direction of the intended/information user while minimizing the signal's quality as received by an eavesdropper. The technique of Artificial Noise AN is also researched in addition to beamforming. The secrecy rate performance measured as Bit-error-ratio BER vs SNR in SIMO system model implemented with the receiving beamforming schemes MRC and EGC suggested that the MRC is considered as an optimal receive beamforming diversity technique in order to achieve a best secrecy rate of transmitted signal and as it was compared to secrecy rate performance resulted from MISO system model

Yagi-Uda antennas are known to be difficult to design and optimize due to their sensitivity at high gain, and the inclusion of numerous parasitic elements. There are various patch antennas used for Wi-Fi and Wi-MAX applications, but with high gain and directionality are requirement. Generally number of directors is raised to increase gain of these antennas. But, here we present modified designs of Yagi-Uda antennas, in which the directivity, gain and bandwidth can be enhanced by different techniques. In this paper initially discuss a design of a conventional Yagi-Uda antenna with four uniform directors is undertaken and uniform spacing between them. Results show that, the proposed techniques would enhance the directivity, gain as well as bandwidth when compared with the first design of Conventional Yagi-uda antenna. Finally, it can be said that the proposed design is suitable for Wi-Fi and Wi-MAX antennas with opertating frequency range starting from 2.45 GHz.

The experiment was conducted to assess the sensitivity of potato yield to dif-ferent irrigation levels at different growth stages. Irrigation levels were determined as percentages (WI 100% as readily available water to the crop (RAW)), and for the rest of the treatments (WII 75%, WIII 50%), as they were applied separately to all four stages of crop growth i.e., vegetative (SI), tuber initiation (SII), tuber bulking SIII, and tuber matu-ration (SIV). The design of complete random sectors was adopted to perform the experi-ments. The results revealed that all the studied parameters: plant height (cm), vegetation plant weight (g), number of tubers per plant, tuber weight (g), tuber yield (ton/ha), and crop water productivity (kg/m3) varied among irrigation water levels at different stages of growth. It was found that the two stages, SII and SIII in potato crops, were more sensitive to deficit irrigation compared to other stages. According to the obtained results, in the case of water abundance conditions, the treatment WII SI can be applied to obtain the highest water crop productivity. In conditions of water scarcity, it becomes necessary to apply the treatment WIII SIII to obtain the highest crop water productivity.

The aim of this work was to establish a temperature of finish rolling stage of Nb/Ti microalloyed steel containing 0.06 wt.% C, 0.77 wt.% Mn, 0.039 wt.% Nb and 0.015 wt.% Ti, using physical simulation. Samples were subjected to laboratory simulation at a twist plastometer at high temperatures, i.e. between 825 and 950 °C. Five pass deformation and interpass times were selected in accordance with a processing parameters at five stand finishing hot strip mill. Restoration (recovery and/or recrystallization) behavior was evaluated by calculation of Fraction Softening (FS) and Area Softening Parameter (ASP) values. At 950 °C all individual pass stress-strain curves, FS and ASP show full recrystallization in all interpass intervals. On the other hand, with a decrease in temperature to the interval of 875-825 °C, the extent of restoration is decreasing, leading to recovery as a sole softening mechanism at 825 °C, which was confirmed by the stress-strain curve shape, and values of FS and ASP. It is assumed that, due to high supersaturation, strain-induced precipitation promoted pinning of grain and subgrain boundaries and suppressed recrystallization. Therefore, the critical temperature for finish rolling was estimated to be 825 °C.