In this paper a new method is proposed to perform the N-Radon orthogonal frequency division multiplexing (OFDM), which are equivalent to 4-quadrature amplitude modulation (QAM), 16-QAM, 64-QAM, 256-QAM, ... etc. in spectral efficiency. This non conventional method is proposed in order to reduce the constellation energy and increase spectral efficiency. The proposed method gives a significant improvement in Bit Error Rate performance, and keeps bandwidth efficiency and spectrum shape as good as conventional Fast Fourier Transform based OFDM. The new structure was tested and compared with conventional OFDM for Additive White Gaussian Noise, flat, and multi-path selective fading channels. Simulation tests were generated for different channels parameters values including multi-path gains vector, multi-path delay time vector, and maximum Doppler shift. © 2009 Springer Science+Business Media, LLC.
In this research, an investigation for the compatibility of the IRI-2016 and ASAPS international models was conducted to evaluate their accuracy in predicting the ionospheric critical frequency parameter (foF2) for the years 2009 and 2014 that represent the minimum and maximum years of solar cycle 24. The calculations of the monthly average foF2 values were performed for three different selected stations distributed over the mid-latitude region. These stations are Athens - Greece (23.7o E, 37.9 o N), El Arenosillo - Spain (-6.78 o E, 37.09 o N), and Je Ju - South Korea (124.53 o E, 33.6 o N). The calculated v
... Show MoreThis paper details the process of designing, analysing, manufacturing, and testing an integrated solid-state hydrogen storage system. Analysis is performed to optimise flow distribution and pressure drop through the channels, and experimental investigations compare the effects of profile shape on the overall power output from the fuel cell. The storing of hydrogen is given much attention in the selection of a storage medium, and the effect of a cooling system to reduce the recharging time of the hydrogen storage vessel. The PTFE seal performed excellently, holding pressure over 60 bar, despite requiring changing each time the cell is opened. The assembly of the vessel was simple and straightforward, and there was no indication of pressure
... Show MoreThe Adaptive Optics technique has been developed to obtain the correction of atmospheric seeing. The purpose of this study is to use the MATLAB program to investigate the performance of an AO system with the most recent AO simulation tools, Objected-Oriented Matlab Adaptive Optics (OOMAO). This was achieved by studying the variables that impact image quality correction, such as observation wavelength bands, atmospheric parameters, telescope parameters, deformable mirror parameters, wavefront sensor parameters, and noise parameters. The results presented a detailed analysis of the factors that influence the image correction process as well as the impact of the AO components on that process
In this work, the theoretical study for designing of dielectric mirrors of high reflectance in the visible region of electromagnetic spectrum between wavelength of 400-700 nm is presented, and searching on the performance properties of the design, like there reflectance as a function to the wavelength, as beam incident in a normal form, for the materials of neglected absorbance, and scattering, in the form of thin film deposition, which are deposited on glass substrate, and by using matrix system in the study, which are used as computer simulation in MATLAB code. The materials which are used in this study are represented by ( AlAs ), (TiO2 ),( SiC ), and (Si3N4 ), which used in the designing mirrors alter
... Show MoreIt is often needed to have circuits that can display the decimal representation of a binary number and specifically in this paper on a 7-segment display. In this paper a circuit that can display the decimal equivalent of an n-bit binary number is designed and it’s behavior is described using Verilog Hardware Descriptive Language (HDL).
This HDL program is then used to configure an FPGA to implement the designed circuit.
Laser is a powerful device that has a wide range of applications in fields ranging from materials science and manufacturing to medicine and fibre optic communications. One remarkable
The Internet of Things (IoT) technology and smart systems are playing a major role in the advanced developments in the world that take place nowadays, especially in multiple privilege systems. There are many smart systems used in daily human life to serve them and facilitate their tasks, such as alarm systems that work to prevent unwanted events or face detection and recognition systems. The main idea of this work is to capture live video using a connected Pi camera, save it, and unlock the electric strike door in several ways; either automatically by displaying a live video connected via USB webcam using a deep learning algorithm of facial recognition and OpenCV or by RFID technology, as well as by detecting abnormal entrance wit
... Show More