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Graphene, which consists of one atomic slide made from the Carbon, and it utilized in various of the implementations like the chemical, the thermal, the mechanical, and the electrical. In this research article, a high gain plasmonic antenna array is proposed for the utilizations of the terahertz (THz) regime on the basis of the graphene material. Also, the surface plasmon polariton (SPP) waves phenomena which emerged at THz in graphene are demonstrated the suggested antenna is composed of (4*6) graphene patches and a graphene Nano ribbon feeder to excite the patches deposed on the lumina layer. The simulated antenna was designed and investigated via the utilizing of the CST software. The obtained outcomes show that the antenna operation frequency bands covered a large band at the 2.6-10, 2.28-2.5, 1.87-2.14, and 1.4-1.6 THz with an S11 ≤ -10 dB and an expedient antenna gain in the operating frequency ranges.

In wireless localization systems, the performance enhancement of location estimation is an important goal. In recent years, different positioning systems using an ultra‐wide band (UWB) technology have been created, and always an evaluation metric to test such systems is needed for ensuring a suitable system for a specified application. Also, a non‐line‐of‐sight (NLOS) identification and mitigation method is needed usually when utilizing the UWB technology. The mean‐square‐error (MSE) and geometric dilution of precision (GDOP) evaluation metrics are widely implemented as standard for choosing a perfect system. In a harsh environment, a novel algorithm of indoor positioning (IP) system is presented using the UWB technology without implementing any NLOS identification and mitigation technique and the localization accuracy is evaluated online. The UWB is used to communicate a mobile station (M) with n anchor nodes distributed randomly and clustered by utilizing a combination method to create different groups, and then a conventional linearized least square (LLS) method is utilized by each group for locating M. A weighted GDOP metric is implemented online to assess the positioning accuracy of each group. Then, the group having the lowest positioning error among other groups is selected to relocate M using a proposed LLS, named modified LLS, for the selected group to enhance the positioning accuracy. The created system outperforms different IP systems in the market for the last decade in terms of time, complexity, and accuracy. The created IP system has a positioning error around 25 cm2 of MSE in a hard environment, which is less than those of different IP systems created recently in the market.

Image registration plays a significant role in the medical image processing field. This paper proposes a development on the accuracy and performance of the Speeded-Up Robust Surf (SURF) algorithm to create Extended Field of View (EFoV) Ultrasound (US) images through applying different matching measures. These measures include Euclidean distance, cityblock distance, variation, and correlation in the matching stage that was built in the SURF algorithm. The US image registration (fusion) was implemented depending on the control points obtained from the used matching measures. The matched points with higher frequency algorithm were proposed in this work to perform and enhance the EFoV for the US images, since the maximum accurate matching points would have been selected. The resulted fused images of these applied methods were evaluated subjectively and objectively. The objective assessment was conducted by calculating the execution time, peak signal to noise ratio (PSNR), and signal to noise ratio (SNR) of the registered images and the reference image which was fused manually by a physician. The results showed that the cityblock distance has the best result since it has the highest PSNR and SNR in addition to the lowest execution time.

The main positioning accuracy metrics that could be used to evaluate an indoor or outdoor positioning system are mean square error (MSE) and geometric dilution of positioning (GDOP). The aforementioned conventional metrics have some limitations such as the math complexity of their expression, and the need for the real value of the target position or the true distance between the target and anchor nodes, which means, in live status, these metrics cannot assess the positioning system and dynamically adjust it. In this study, we present a novel positioning accuracy evaluation metric named weighted position (WP) that could be used to evaluate the system online. The created metric neither needs for the real value of the target position nor the real distances between the target and anchor nodes. It is based only on the measured distances and was experimentally evaluated based on the comparison between it and the MSE built-in Matlab function using Matlab simulation, and real experiment using Ultra-wideband (UWB) technology as a communication means between the target and anchor nodes. The behavior of the WP metric perfectly follows the behavior of the MSE function. It will help in creating and modifying a positioning system online until obtaining an accuracy that satisfies the user requirement.

In recent years, indoor positioning system (IPS) plays a very important role in several environments such as hospitals, airports, males, Etc. It is used to locate mobile stations such as human and robots inside buildings. Some of IPSs applications are: locating an elder or child needed for an urgent help in hospitals, emergency situations such as locating firefighters inside building on fire or policemen fitting terrorists inside building by a commander to help for expedite evacuation in case one of them need for help. In indoor positioning applications, the accuracy should be high as can as possible, in another word; the error should be less than 1 meter. The indoor environment is the major challenging to obtain such accuracy. In this paper, we present a novel algorithm to identify the line of sight (LOS) and non-line of sight (NLOS) channels and improve the positioning accuracy using ultra-wideband (UWB) technology implementing DW1000 devices.In recent years, indoor positioning system (IPS) plays a very important role in several environments such as hospitals, airports, males, Etc. It is used to locate mobile stations such as human and robots inside buildings. Some of IPSs applications are: locating an elder or child needed for an urgent help in hospitals, emergency situations such as locating firefighters inside building on fire or policemen fitting terrorists inside building by a commander to help for expedite evacuation in case one of them need for help. In indoor positioning applications, the accuracy should be high as can as possible, in another word; the error should be less than 1 meter. The indoor environment is the major challenging to obtain such accuracy. In this paper, we present a novel algorithm to identify the line of sight (LOS) and non-line of sight (NLOS) channels and improve the positioning accuracy using ultra-wideband (UWB) technology implementing DW1000 devices.