Shaping of the conductor or any of the other parts of the patch radiators plays important role in changing the working parameters of this type of antennas. In this work Annular, shape has been introduced on the conductor patch. Different dimensions have been introduced on the annular geometry and with a help of a simulation package obtained results are dependable on for application in microwave frequency ranging from 2.5 GHz to 5 GHz. Encouraging values of Bandwidth have been obtained with reasonable output of return loss

This paper presents the design and simulation of a microstrip array patch antenna operating at 28 GHz for 5G communication with a maximum reflection coefficient of -17 dB, a very wide bandwidth of 1.5 GHz and a high gain of 6.84 dB. A Roger RT5880, which has a dielectric constant of 2.2 and a height of 0.2 mm has been used as a transmission line with an inset feed. Antenna dimensions were calculated and simulated results have been performed and analyzed using CST Microwave Studio Package. Moreover, linear array with 3x1 and 5x1, to provide better gain to reach 13 dB and reducing the mutual effect, was developed using decoupling simple slab techniques.

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.