Papers by Abdelhalim Zekry
2016 IEEE 43rd Photovoltaic Specialists Conference (PVSC), 2016
This paper aims to present the design and simulation of two proposed low cost solar cell structur... more This paper aims to present the design and simulation of two proposed low cost solar cell structures; namely, pn and npn. Both structures are based on commercially available low cost heavily doped silicon wafers. Their operation relies on the idea of vertical generation and lateral collection of the light generated carriers. A detailed qualitative analysis of both structures is given and verified using advanced TCAD tools. The comparison is analyzed firstly regarding the illuminated IV characteristics. The open circuit voltage (Voc), short circuit current density (Jsc), fill factor (F.F) and conversion efficiency (η) are calculated. Additionally, the optical performance is calculated and compared for both structures. The quantum efficiency, the spectral response and the absorption curve are compared. The presented results show that npn structure gives better electrical and optical performance than the pn one.
international journal of engineering trends and technology, 2015
Software Defined Radio (SDR) is a flexible radio architecture which can be configured to adapt va... more Software Defined Radio (SDR) is a flexible radio architecture which can be configured to adapt various waveforms, frequency bands, bandwidths, modes of operations and wireless standards such as Global System of Mobile communications (GSM) by altering the physical layer behavior through changes in its software. In this paper, The baseband section of GSM wireless receiver which includes Source Decoding, Channel Decoding, De-interleaver, Demodulation and Frequency De-hopping (FH) has been tested, simulated and designed for implementation using SDR. And the Bit Error Rates (BER) has been calculated for different modulation schemes namely, Binary Frequency Shift Keying (BFSK), Binary Phase Shift Keying (BPSK), and Quadrature Phase Shift Keying (QPSK), and Eight Phase Shift Keying (8PSK). These four models have been evaluated considering an additive white Gaussian noise channel (AWGN). Then the performance of the receiver has been analyzed by comparing the input and output waveforms with ...
Energies
In this work, we report on the effect of substituting the active intrinsic i-layer on a conventio... more In this work, we report on the effect of substituting the active intrinsic i-layer on a conventional pin structure of lead-free perovskite solar cell (PSC) by a homo p-n junction, keeping the thickness of the active layer constant. It is expected that when the active i-layer is substituted by a p-n homo junction, one can increase the collection efficiency of the photo-generated electrons and holes due to the built-in electric field of the homo junction. The impact of the technological and physical device parameters on the performance parameters of the solar cell have been worked out. It was found that p-side thickness must be wider than the n-side, while its acceptor concentration should be slightly lower than the donor concentration of the n-side to achieve maximum efficiency. In addition, different absorber types, namely, i-absorber, n-absorber and p-absorber, are compared to the proposed pn-absorber, showing a performance-boosting effect when using the latter. Moreover, the propo...
Ain Shams Engineering Journal
Journal of Computational Electronics
Journal of Communications
This work introduces an enhanced optical wireless Line of Sight (LOS) indoor localization system ... more This work introduces an enhanced optical wireless Line of Sight (LOS) indoor localization system based on Visible Light Communication (VLC) technology using Light-Emitting Diodes (LEDs) as optical sources. Although Received Signal Strength Indication (RSSI) localization algorithm is simple and needs no extra hardware to be installed, but its performance is poor at some received areas compared to Time Difference of Arrival (TDOA) technique. That is because RSSI technique depends on the received power strength which is degraded towards room corners. Therefore, the proposed system is a combination between RSSI and TDOA algorithms and the target position is estimated using RSSI only at places with acceptable received electrical power (1.04x10-8 W or between 6.53x10-9 to 9.92x10-9 W) while TDOA will be used at the other positions. Thus, this hybrid localization system will decrease the root mean-squared-error (RMSE) from 7.34cm using RSSI technique only on the whole received area to 5.81cm (using this hybrid system) and will save time. Some parameters that affect the performance of both RSSI and TDOA techniques are also included in this work in order to select the suitable values in the hybrid localization system. This work is evaluated by using MATLAB software version 2013. Index Terms-Light-emitting diode, line of sight, visible light communications, radio frequency, received signal strength indication, root mean-squared-error, time difference of arrival I.
International Journal of Communication Systems
Multimedia Tools and Applications
ABSTRACT The book introduces an overview about one of the third generation (3G) mobile networks, ... more ABSTRACT The book introduces an overview about one of the third generation (3G) mobile networks, known as Universal Mobile Telecommunications System (UMTS) networks, which consists of Universal Terrestrial Radio Access Network (UTRAN) and the Core Network (CN). The UTRAN has many interfaces, but the book focuses on the Uu interface which is between the User Equipment (UE) and the UTRAN. That interface is based on Wideband Code Division Multiple Accessing (WCDMA) system. The protocol architecture of UMTS is composed of two planes; the control plane and the user plane. The book is concerned on the control plane which has the Radio Resources Control (RRC) protocol to manage the control signal at the Uu interface between the UE and the Radio Network Controller. The main goal of the book is to design, implement and test the building blocks of Radio Resources Controller of the WCDMA system. Also, the book presents one of nuclear applications that is based on WCDMA. This application includes design, implementation and simulation of Radiation Monitoring network as a pilot prototype model.
2012 Seventh International Conference on Computer Engineering Systems, 2012
ABSTRACT Most Bluetooth implementations focus on architecture, routing protocols, encryption, and... more ABSTRACT Most Bluetooth implementations focus on architecture, routing protocols, encryption, and performance evaluation of the network. This paper provides a brief description of the Bluetooth standard including the physical layer. It focuses on developing MatLab/Simulink models for the Bluetooth transceivers utilizing different modulation schemes and the performance evaluation of these models. Different pulse shaping waveforms are utilized in our Matlab/Simulink Bluetooth models. The performance of our Bluetooth transceiver models with AWGN channel is evaluated by means of the BER.
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Papers by Abdelhalim Zekry