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Questions related from Abdelhalim abdelnaby Zekry
To the colleagues who are interested in multi level power inverters, i would like that they see this paper on the stepped sinewave inverter which is published on the journal of solar cells in...
12 February 2015 3,841 4 View
The channel capacity decreases with distance from the base station as a consequence of the the decreasing the signal to noise ratio in LTE systems. At the cell boundary, normally Bpsk modulation...
26 December 2014 1,769 9 View
In multiple input multiple output wireless communication systems the different paths of the signals from the transmitter antennas to the receivers must be independent to separate these signals at...
09 December 2014 3,188 8 View
It is estimated that the energy consumption of the communication and information equipment is about five percent of the the global energy consumption which amounts to 20000 Twh.This needs power...
06 May 2014 2,001 33 View
In the information technology new generations of computers especially the PCs are produced. This is also valid in the communication technology which is changing in high rate from the first...
20 March 2014 2,027 6 View
The organic semiconductors are gaining land in electronics. They are characterized by lower temperature processing and thin film structures. We can find now commercial organic semiconductor...
18 February 2014 877 24 View
It is required to trim the wavelength of the emitted light from light emitting diodes. Can this be accomplished by varying the operating temperature of the diode or by any other means?
18 February 2014 6,831 6 View
It is required to establish a master of science training laboratory in photovoltaics. What are the necessary equipment required to set up such laboratory? Please give detailed specifications and...
05 January 2014 3,573 3 View
What are the required laboratory and testing equipment to set up an advanced electronic communications laboratory for research?
22 December 2013 3,598 18 View
In digital communication systems one can trade off the bandwidth of the signal and its power by changing the number of bits per symbol to transmit the same information. This gives the digital...
15 November 2013 3,498 12 View
The life span of solar panels has been greatly improved over time since the introduction of the commercial solar panels in the seventies of the last century. Some experienced manufacturers grantee...
27 September 2013 9,599 17 View
Frequency synthesizers generate discrete frequencies with crystal stability. They have become an integral part of advanced communication systems in general and wireless communication systems in...
04 June 2013 8,339 5 View
The silicon solar cell is composed of a p-substrate and an n+- emitter. In this forum I wish to discuss the effect of the substrate parameters on the performance of solar cells.The parameters of...
30 May 2013 7,571 21 View
In this forum it is required to discuss the effect of the n emitter layer parameters on the the conversion efficiency of the Si np solar cells. These parameters are the junction depth, the doping...
23 May 2013 4,805 8 View
Claude Shanon derived an equation governing the maximum channel capacity on a communication link. Shanon stated that C= B log2 (1+S/N). C is measured in bits per second, B the bandwidth of the...
14 May 2013 5,731 13 View
All bipolar devices including LEDS and solar cells have emitter layers which injects minority carriers into adjacent base region. According to the Shockley theory , the emitter is characterized by...
23 April 2013 7,759 3 View
Increasing the current in a white LED above specific value leads to decrease in the luminous efficacy. The efficacy of the LED under this current is appreciably higher than the conventional...
09 April 2013 6,178 6 View
One used solar grade silicon to produce high efficiency solar cells. Solar grade silicon has a doping concentration of about 10^17/cm^3. If one succeeds to make such cells, then he can use less...
28 March 2013 1,455 11 View
