layth mohammed ali shakir shakir

Enhancing the capacity of wireless communications systems is necessary to manage growing networks. Thus, this work presents an analytical model for describing the deterioration in orbital angular momentum (OAM). The proposed model is based on a uniform circular array, which can be applied in OAM generation to obtain the desired beam properties. First, the side-lobe problem in OAM applications is examined and resolved by optimizing the beam synthetization. Then, comparisons between the two window techniques are used to evaluate their impacts. Finally, the effects of selecting the optimal window technique and width on the solutions are investigated. Numerical results and the comparisons between derived formulas and those obtained via full-wave numerical simulations are shown.

Graphene nanosheets were fabricated on a metal (Al) substrate by using a chemical spray method. Annealing process has been applied to reducing the concentration of carbon and to increase the sheet hardness. Surface morphology measured by metallurgical microscope Device Corporation, X 1600. Thermal camera was used to measure the performance of coated heat sink. The temperature was measured from the two sides, one from heat sink side, and the other one is from power transistor side. The results showed that the temperature of the transistor was decreased by about 4.3 °C in the case of heat sink coating with 80 μm layer thickness while decreased by 6.9 °C in the case of the heat sink coating with 120 μm layer thickness.

This work is intended to deliver an intelligent traffic system using radio frequency identification (RFID) technology. It designed and implemented in a way where fines are autonomously registered. In addition, a mobile app was built to assist traffic officers managing their field works. Low cost equipment’s have been used such as RFID technology, passive tags, processing unit (personal computer), and a connection system. First stage is represented by collecting data using the RFID, where it reads any identified tag that attached with vehicles. Next, a certain data are transmitted to the server using internet network communication system. The server is responsible for processing these data according to a pre-defined rules. Finally, police officers can use the mobile app to perform several tasks according the processed data such as monitoring a specific car, register a new car ID and others.