The characteristic of li fi technology

1. International Journal of Computation and Applied Sciences IJOCAAS, Volume2, Issue 2, April 2017, ISSN: 2399-450
51

Abstract— The operation of widespread is currently wireless
transmission methods, such as Wi-Fi, WiMAX, LTE, etc., based
on the use of radio frequency channels. This mechanism has
several disadvantages. In particular, band limitation, several
interference sources in the same frequency band, data rate
dependent on the number of users and others. These technologies
have less widespread nowadays, but a promising alternative Li-
Fi, which is based on the energy of light.
Index Terms— Optical communication equipment, Optical
transmitters, Optical receivers, Wi-Fi, Light Fidelity (Li-Fi),
transceiver module, modulation, Visible light communication,
OFDM.
I. INTRODUCTION
ireless technologies are relevant in various active at the
present time. It is interesting to compare the wireless
Wi-Fi technology and Li-Fi to expand the areas of their
application.
Use of wireless data transfer increases in geometrical
progression every year, but the range of available frequencies
not fixable and becomes less. Li-Fi is a wireless
communication system which used a light to bring a signal
instead of customary radio frequencies in Wi-Fi Technology.
Li-Fi is a technology which used light of LEDs for wireless
data transfer. Visible Light Communication (VLC) uses
superfast pulses of light for transfer information which remain
imperceptible for human eyes.
Most of us are familiar with the Wi-Fi, which operates at a
frequency of 2.4 - 5 GHz, implementing wireless access to the
Internet at home, schools, offices and in other public places.
The Wi-Fi technology became are very dependent on this
ubiquitous technology. But, as well as the majority of
technologies, it has restrictions.
Wi-Fi can cover the whole house, otherwise its speed of
connection is restricted 50-100 MB a second, using
IEEE802.11n. It is a good index for many modern services,
but there isn't enough for trensfer a huge data packets as HD
movies, qualitative music and video games. What to become
more dependent on "cloud" or "media services" for storage a
personal files, including movies, music, photos and games,
required high data transfer rate. Therefore, the technology
based on radio frequency, such as, Wi-Fi - is not the best
solution. Moreover, Wi-Fi may not be the most efficient
solution to provide advanced features, such as Indoor
positioning system and Gesture recognition.
Wi-Fi - a wireless data transmission technology over the air.
The principles of Wi-Fi is closed as the following, Wi-Fi
adapter converts flow data into an electric signal and transmits
it through an antenna [1]. The router of Wi-Fi receives the
radio signal and decodes it, sends the data via the physical,
wired connection. And the signal conversion may also occur
in the backwards direction. The router receives the
information from the Internet and translates it into a radio
signal, which is then transmitted to a wireless computer
adapter. To use Wi-Fi must be the appropriate equipment
wirelessly. All equipment is divided into two groups: Access
point and a wireless router.
In our University (University of Technology, Iraq) our
researchers try hard to investigate in most/all branches of
science [12-38]
Optical wireless communications (OWC), and recently – Li-
Fi, offer absolutely new approach to wireless technologies
from the point of view of data transmission rate, flexibility and
comfort of operation.
II. COMPARATIVE ANALYSIS OF LI-FI AND WI-FI
TECHNOLOGY
Li-Fi - is a developed wireless data transmission technology
using light. Li-Fi consists of four main components: an LED
lamp, a radio frequency power amplifier, the printed circuit
board and Cases [2]. The printed circuit board controls the
electrical inputs and outputs of the microcontroller and the
lamp is used for controlling a variety of lamp functions. The
RF signal generated in the RF power amplifier and sent to the
electric field of the lamp. The high concentration of energy in
an electric field vaporizes the contents of the flask into a
plasma state in the center of the lamp; the plasma generates an
intense light source. All of them are contained in an aluminum
casing.
The principle of Li-Fi is to change the settings of the LED
lamps with a very high speed, which is not visible to the
human eye. The process controls the special microchip that
encodes information. A particular photo-detector detects light
beams and performs inverse data conversion.
The Li-Fi technology used transceiver instead modems in Wi-
Fi, it's equipped with LED lamps that can transmit and receive
information, and at the same time be used for room lighting.
LED lamps are the access point to any number of users.
Currently, the transmission rate of this technology is 10Gbit/s;
in laboratory conditions have reached 15Gbit/s [3]. But the
data stream can be interrupted by any obstacle. This
The Characteristic of Li-Fi Technology
Comparing with Wi-Fi
Dr. Hussam Dheaa Kamel, Hadi Jameel Hadi
W

2. International Journal of Computation and Applied Sciences IJOCAAS, Volume2, Issue 2, April 2017, ISSN: 2399-450
52
disadvantage can be an advantage if you do not want the data
network used by outsiders.
While the operating range of frequencies of networks on the
basis of Wi-fi and WiMax technologies is loaded by users, and
congestion of any transmission channel leads to a natural
speed reduction of data transfer on this channel, because of
need of serial use of this channel, the Li-Fi networks can
transmit a signal to unlimited number of users in a cover zone
without negative interference at each other of the signals
accepted by users.
Clients of radio-frequency data communication networks can
create noises in the network to other its users or create noises
to other networks which are crossed on operating range of
frequencies. Collisions of signals from different networks can
result from such intersections. If signals of one network
interfere with different productions of the enterprises or will
put in data communication networks of medical institutions,
transport and scientific organizations and on a network of
mass media, then it can lead to serious negative consequences.
that is quite possible because for example, the Wi-fi networks
on the basis of standards 802.11b, 802.11g, 802.11n of 2,4
GHz which are on operating frequency can be crossed with the
LTE networks which operating range of frequencies is defined
in an interval from 0,7 GHz to 2,7 GHz in the Russian
Federation today. The operating range of the Li-Fi networks is
far beyond these limits therefore the VLC networks on the
basis of LEDs of visible radiation are suitable for use in zones
sensitive to radio waves. On the radio-frequency data
communication networks there is a need of paid extension of
admissible frequency band which is restricted, and for the Li-
Fi networks separation of an additional band is free and
doesn't require the procedure of licensing that simplifies use of
Li-Fi technology. Besides, radio-frequency technologies of
data transfer can exert a negative impact on a human body
[11] and though influence of the Li-Fi networks isn't studied,
there are researches showing that LED light is the most
comfortable for human eyes. Radius of action of networks on
Li-Fi technology allows covering completely with a signal the
closed target location (an office, audience, the hall) and won't
begin to quit out of its limits, unlike radio-frequency
technologies that speaks about higher level of confidentiality
of data, about easier way of their protection against illegal
access. Engineers of institute of telecommunications of
Fraunhofer are capable to transfer data with speed
800mbit/sec. in a sq. m zone 10 on this technology. It does Li-
Fi technology by the excellent decision for deployment of
wireless network in house conditions.
Influence of the noise created by environmental light restricts
use of technology in the locations which are well lit by a
sunlight, on open spaces and creates need of observance of
conditions for good transparency between a LED radiator and
the photodiode, so, for example if in between there is a hand,
then transmission will be interrupted.
It is much simpler to Li-Fi network to build in the existing
infrastructure, than the majority of data communication
networks on the basis of other technologies. Exponentiation of
base stations isn't required, and lighting engineering is present
everywhere and creation of the Li-Fi networks will require
only use for lighting of LED lamps with coders (with
modulators). At the same time there is need for big additional
power expenses that also considerably reduces the price of its
operation.
The comparative characteristics of the considered technologies
(Tab. I, II).
According to the creator Harald Haas Li-Fi technology in a
short time reach data transfer speeds of over 100 Gb/s, and
completely replace Wi-Fi technology [4].
III. PHYSICAL CHARACTERISTICS STANDARD IEEE 802.15.7
Li-Fi and Wi-Fi Technologies based on similar protocols
IEEE 802.11.However, Li-Fi uses electromagnetic waves of
visible light, while Wi-Fi - the radio waves.
Due to this, the first technology gains an advantage in terms
of higher bandwidth.
IEEE 802.15.7 standard defines for Li-Fi physical layer
network model OSI PHY (Physical layer), and a MAC address
(Media Access Control). Working version of the IEEE
802.15.7 identifies three the PHY with different bandwidth,
which are presented in Table 3.
TABLE I
COMPARATIVE CHARACTERISTICS
Technologies
Operating Modes
(frequency) Data Rate
Wi-Fi 2.4 GHz 11-300Mbit / s
Li-Fi 100 MHz, 10 Gbit / s
TABLE II
ADVANTAGE & DISADVANTAGE OF LI-FI
Technologies Advantages disadvantages Common
signs
Wi-Fi without paving the
cable network
operation
with 2.4 GHz
remote
access
networks
access to any
network devices
small
electromagnet
ic capacity
component
the free movement
of consumers, the
creation of groups
of users
low reliability
Li-Fi cheap components data transfer
can be carried
out only
within the
line of sight
transceive
r module
radio access
underwater and in
the air
safety effects on
human health
Provide
information
Security

3. International Journal of Computation and Applied Sciences IJOCAAS, Volume2, Issue 2, April 2017, ISSN: 2399-450
53
Light Fidelity has a significantly higher data rate compared
with Wi-Fi,. However, Li-Fi technology is able to distribute
the signal a smaller range than radio waves.
Most likely, complete extrusion of Wi-Fi Light Fidelity
technology won't happen. Li-Fi developers assume that the
product will come to the mass market not earlier, than in 3-4
years. LED routers will be used in a combination with Wi-Fi.
It is caused by presence at luminous technology of data
transfer of unresolved problems.
In particular, it is difficult to Li-Fi to apply on the street
therefore this section can be serviced by Wi-fi. If Harald
Haas's vision also is realized and any bulb will be able to
distribute a signal, then you shouldn't expect it in the near
future. The most probable scenario is complex use of Li-Fi
and Wi-Fi.
In the licensed and unlicensed frequency ranges (the
technology HetNet, LWA, LAA, eLAA, Multefire and others)
can get acquainted with technical features of functioning of
networks of mobile communication in the book of "Mobile
Communication on the Way to 6G".
IV. PRINCIPLE OF OPERATION OF LI-FI
The heart of Li-fi technology is high brightness LED’s.
These Light Emitting Diodes can be switched on and off very
quickly which gives you the opportunities for transmitting
data since operating speed of an LED is less than
1μs.Iimperceptible for a human eye therefore for the person
will seem as if light works permanently. This invisible on/off
switching allows transferring data with use of the binary code.
Switching on – logical "1", switching off – logical "0". Such
principle allows encoding data in light by change of speed of
flicker of a LED. Modulation happens so quickly that a human
eye doesn't manage to note it. The photo-sensor element
receives a signal and will transform it back to basic data. This
method is the use of fast light pulses to transmit information
via wireless technology refers to the OWC, its high capacity
allows to compete with Wi-Fi technology. Li-Fi is faster and
cheaper version of Wi-Fi, which operates in the visible
wavelength range. The Visible light communication is a data
communications medium using visible light between 400 THz
(780 nm) and 800 THz (375 nm) at the same time as the
optical medium of data and lighting of location [2].
Visible light is not harmful to vision. A typical example of use
visible light communications is shown in Fig.2.
Using a microlED lamp, it was succeeded to reach data
transmission rate of 3, 5 Gbit/sec. through each of three
flowers - red, green and blue, - which together make up the
white light [9]. This means that the folding of the spectral
channels can transfer data at a total rate of 10 Gbit / s. Reset
signal from the LEDs and photodiodes used fast enough in
order not to pause as for its reliable attenuation.
For the organization of fedback data network based on Li-Fi
technology requires the combined use with other transmission
technologies such as PowerLAN(direct Lan, or PLC - Power
Line Communication), the essence of which lies in the
transmission of data on the power lines or high-speed infrared
data transmission Very Fast Infrared (VFIR) or Ultra-Fast
Infrared (UFIR).
Fig. 2 shows schematically shown local data network based
on a combination of technology Li-Fi technology and VFIR
feedback where Li¬Fi-transmitter contains a photodiode
Fig. 2. Schematical representation of a local area network of Li-Fi
Fig.1 Working of Li-Fi
Server
Internet
Streaming
content
Lamp
Driver
Power
Lamp
Led
Receiving
App Data
PC
Amplification
& Processing
Photo
Detector
Receiver
Dongle
TABLE III
PHYSICAL LAYER CHARACTERISTICS STANDARD IEEE 802.15.7
PHY I PHY II PHY III
Application
area
External
application.
Applications
with a small
amount of data
indoors Multiple sources
and
receiversRGB
Speed,
Mbit / s
≈ 0,012 – 0,268 1,25 - 96 12 - 96
Error
correction
algorithm
Convolutional.
Reed Solomen
Reed
Solomen
Reed Solomen
modulatio
n Types
OOK (On-off
keying).
VPPM
(Variable pulse
position
modulation)
OOK (On-off
keying).
VPPM
(Variable
pulse position
modulation)
CSK (Colour
shift keying)

4. International Journal of Computation and Applied Sciences IJOCAAS, Volume2, Issue 2, April 2017, ISSN: 2399-450
54
receiver, decoder, infrared emitter, as well as USB-interface.”
V. REVOLUTION OF LI-FI TECHNOLOGY IN WIRELESS DATA
TRANSMISSION
The ancestor of luminous technology Haas believes that the
advantages of Li-Fi will make a luminous network demanded
in the digital world. According to him, Wi-Fi won't be able to
conform to requirements of mobile data transfer which are
imposed by the concept of the Internet of things. By 2020,
each user will account for approximately three network
devices. In real indices – about 20,8 billion connections. If all
devices begin to use the same frequencies of Wi-Fi, then on a
network there will be noises that negatively will affect data
transmission rates. For the second half of the third decade the
situation will only become aggravated. An effective solution
would be, according to Haas, Light Fidelity technology by
which to distribute the signal to be adapted to any given
function lamps.
VI. TERMS OF REALIZATION OF LI-FI TECHNOLOGY
Today the speech about commercial start of Li-Fi doesn't
go. However the higher the frequency of use of LED lamps,
the great opportunities open for distribution of luminous data
transfer. Any LED can light at the same time location and
broadcast arrays of binary data. According to the researches
Grand View Research, by 2024 the market of luminous
technology of data transfer will grow to 100 bln. dollars.
PureLiF founded by Harald Haas is considered the main
company which is engaged in a research, development and
advance of Li-Fi. However interest in technology is shown by
other commercial structures. For example, tests of Li-Fi
carried out by Beam caster, having reached 1,25 Gbits, and
the Sisoft company which transferred data with speed of 10
Gbits.
In the fall of 2016 there was information that the Lucibel
company specializing in LED lighting with which PureLiF
cooperates is ready to realize the project on equipment of the
first-ever office double-side data transfer on Li-Fi technology.
It is planned to implement the decision in Paris.
Other French company, Oledcomm, according to the
received tender, shall equip over 60 stations of the Parisian
subway of 250 thousand LED light sources. In this project the
Li-Fi technology will use one-sided communication. For
example, to transfer information on layout of objects.
Also information on testing of data transfer by means of the
luminous radiation of Li-Fi is found in a code of the iOS
operating system of the Apple Company.
VII. OFDM IN VISIBLE LIGHT SYSTEM MODEL
The main building blocks of an OFDM-based transmitter and
receiver systems are illustrated in Fig. 3. Since OFDM is
based on IFFT and FFT algorithms, the implementation on the
DSP is straightforward. On the OFDM Tx board, FEC coding
is implemented. This is based on a rate 1/2 convolution
encoder. A time interleave is applied. At the receiver, Viterbi
decoding with hard decision output is used.
In general a time varying, flat fading channel is assumed. It is
further assumed that the channel remains constant within one
OFDM frame. Since, however, no well established models for
this particular propagation system exist, some
overprovisioning in the system design is accepted. With this
approach the above made assumptions are to be confirmed.
For the purpose of channel estimation and synchronisation,
training sequences and pilots are used [6].
Concretely, the OFDM frame as implemented in the
experimental system is formed by a time synchronization
signal (sinusoidal signal), four OFDM symbols for the training
sequence, and 20 OFDM symbols with data sub-channels
carrying the modulated information (see Fig. 4). The channel
transfer factors are obtained using the training sequence and
averaging over the four training sequence periods for every
subcarrier [7, 8].
In the Fig. 4, OFDM frame structure: Four OFDM symbols
carrying a training sequence are used for channel estimation.
The data symbols are transmitted in the consecutive 20 OFDM
symbols. Each of these symbols uses four subcarriers for pilot
transmission.
Maximum speed of switching of LEDs is restricted to a
method of their production which defines their resistance to
burnout; the same stability doesn't allow using luminescent
lamps and glow lamps for data transfer on VLC technology.
QPSK modulation on the luminous flux radiated by white
LEDs superimposing of data by means of modulations
happens by method of optical multiplexing to orthogonal
frequency de-multiplication of channels Optical orthogonal
frequency-division multiplexing (O-OFDM) with the
quadrature phase manipulation. In practice the O-OFDM
method is implemented by means of an algorithm of FFT, that
is the discrete transform of Fourier.
VIII. CONCLUSION
The Li-Fi technology uses the visible light instead of radio
waves, it has a high data transmission rate. If to take as a basis
224 GB/S, then Li-Fi exceeds the speed limit of the IEEE
802.11ax Wi-Fi-standard by 22,4 times, and IEEE 802.11ac –
by 30 times.
The Li-Fi technology is its rather high security from hacker
penetration. The matter is that light which is been the basis for
transmission doesn't pass through walls. Therefore for
Fig. 4. OFDM frame structure
synchronizatio
n
Channel
Estimation
Training
Sequence
Data and Pilots
OFDM Frame (90ms)
4 Symbol
OFDM
4 Symbol OFDM

5. International Journal of Computation and Applied Sciences IJOCAAS, Volume2, Issue 2, April 2017, ISSN: 2399-450
55
cracking of the Li-Fi network the malefactor shall be in close
proximity to a signal source, thereby losing the anonymity.
Promotes optimization of energy consumption integrating
system of lighting and hot spots.Li-Fi-devices do not create
interference to each other on the network.
REFERENCES
[1] D. Tse, P. Viswanath, Fundamentals of Wireless Communication
Cambridge University Press, June 2005.
[2] M. Mutthamma, “A survey on Transmission of data through
illumination- Li-Fi”, International Journal of Research in Computer and
Communication Technology, Vol 2, Issue 12, December- 2013.
[3] Vega, Anna (14 July 2014). "Li-fi record data transmission of 10Gbps
set using LED lights". Engineering and Technology Magazine.
Retrieved 29 November 2015.
[4] "IEEE 802.15 WPAN Task Group 7 (TG7) Visible Light
Communication" IEEE Standards Association. April 9, 2011. Retrieved
9 Dec 2011.
[5] An IEEE Standard for Visible Light Communications
visiblelightcomm.com, dated April 2011. It is superfast modern intelnet
technology.
[6] H. Schober, F. Jondral, R. Gallacher, and Z. Wang, “Adaptive Channel
Estimation for OFDM Based High Speed Mobile Communication
Systems,” IEEE International Conference on Third Generation
Wirelessand Beyond 2001, pp. 392–397, May 2001.
[7] H. Arslan and T. Ycek, “Estimation of Frequency Selectivity for OFDM
Based New Generation Wireless Communication Systems,” World
WirelessCongress, May 2003.
[8] V. A. Loshakov, H.D. Al-Janabi, Y. T. Hussein, N. T. Nasif. “Adaptive
modulation in LTE technology by using OFDMA and SC-FDMA with
MIMO”, Восточно-Европейскийжурналпередовыхтехнологий (ISSN
1729-3774). – 2013. – Vol. 2/9 (62).
[9] J. Condliffe, “Will Li-Fi be the new Wi-Fi”, New Scientist magazine.
2011. No. 2822. P. 18.
[10] Hanzo, L., Haas, H., Imre, S., O'Brien, D., Rupp, M. & Gyongyosi, L.
“Wireless Myths, Realities and Futures: From 3G/4G to Optical and
Quantum Wireless”, Proc. IEEE. 2012. Vol. 100. P. 1853-1888. ISSN
0018-9219.
[11] H. A. Kazem and M. T. Chaichan, "Experimental analysis of the
performance characteristics of PEM fuel cells," International Journal of
Scientific & Engineering Research, vol. 7, no. 2, pp. 49-56, 2016.
[12] Avendano C., Mata A., Sarmiento С., Doncel G. “Use of laptop
computers connected to internet through Wi-Fi decreases human sperm
motility and increases sperm DNA fragmentation ” Fertility and
Sterility. 2012. Vol. 97, Issue 1. P. 39-45.e2. ISSN 00150282.
[13] H. A. Kazem, M. T. Chaichan, S. A. Saif, A. A. Dawood, S. A. Salim,
A. A. Rashid, A. A. Alwaeli, "Experimental investigation of dust type
effect on photovoltaic systems in north region, Oman," International
Journal of Scientific & Engineering Research, vol. 6, No. 7, pp. 293-
298, 2015.
[14] R. J. Al-Azawi, "Stability of a multi-step recovery process when
catastrophe varying intensity", Technology Audit and Production
Reserves, vol. 5, No. 4, 2013.
[15] M. T. Chaichan and H. A. Kazem, "Experimental analysis of solar
intensity on photovoltaic in hot and humid weather conditions,"
International Journal of Scientific & Engineering Research, vol. 7, no. 3,
91-96, 2016.
[16] R.J. Al-Azawi, “A Dynamic Model of Markovian Human-Machine-
Environment System that is Effected by Some Hazard”, Innovation
Potential of Ukrainian science- the twenty-first century, vol. 20, 2013.
[17] I.V. Naumeyko, R.J. Al-Azawi, W.A. Al-Refaai, “Markov Model of
Unsteady Flow Elimination of Accidents In Restrictions on The
Performance of The Operator“, Eastern-European Journal of Enterprise
Technologies, 3(4), 63-68, 2013.
[18] H. A. Kazem, A. H. A. Al-Waeli, M. T. Chaichan, A. S. Al-Mamari, A.
H. Al-Kabi, "Design, measurement and evaluation of photovoltaic
pumping system for rural areas in Oman", Environ Dev. Sustain, 2016.
DOI 10.1007/s10668-016-9773-z.
[19] A.H. Kadhum, R. S. Jawad, R.J. Al-Azawi “Determination the wear rate
by using XRF technique for Kovar alloy under lubricated condition”,
International Journal of Computation and Applied Sciences IJOCAAS
2(1), 1-5, 2017.
[20] M. T. Chaichan, "Enhancing productivity of concentrating solar
distillating system accompanied with PCM at hot climate", Wulevina,
vol. 23, No. 5, pp. 1-18, 2016.
[21] R. J. Al-Azawi, A.H. Kadhum, R. S. Jawad, “ Mathematical Model of
Reliability of Restored Technical System”, International Journal of
Computation and Applied Sciences IJOCAAS 2(1), 23-26, 2017.
[22] Ali H. Al-Waeli, Hussein A Kazem, Miqdam T Chaichan, Review and
design of a standalone PV system performance, International Journal of
Computation and Applied Sciences IJOCAAS, vol. 1, No. 1, pp: 1-6,
2016.
[23] И. В. Наумейко, "Анализ псевдохаотического поведения
кейнсианских моделей экономики / И. В. Наумейко, Р. Дж. Аль-
Азави," В. А. Алрефаи // Вестник национального технического
университета “ХПИ. 26С, 59–64, 2013.
[24] H. A. Kazem, A. H. A. Al-Waeli, A. S. A. Al-Mamari, A. H. K. Al-
Kabi, M. T. Chaichan, "A photovoltaic application in car parking lights
with recycled batteries: A techno-economic study", Australian Journal of
Basic and Applied Science, vol. 9, No. 36, pp: 43-49, 2015 .
[25] M. T. Chaichan, S. H. Kamel & A. N. M. Al-Ajeely, "Thermal
conductivity enhancement by using nano-material in phase change
material for latent heat thermal energy storage Systems", SAUSSUREA,
vol. 5, No. 6, pp. 48-55, 2015 .
[26] Наумейко И. В. Модели систем «Человек-Машина-Среда» с вос-
становлением при неклассических потоках событий / И. В.
Наумейко, Р. Дж. Аль-Азави // Восточно-Европейского журнала
передовых технологий. – 2013. – № 2/10 (62). – С. 55–58.
[27] M. T. Chaichan, K. I. Abaas, H. A. Kazem, "Design and assessment of
solar concentrator distillating system using phase change materials
(PCM) suitable for desertec weathers," Desalination and water
treatment, vol. 57, no. 37, pp: 14897-14907, 2015. DOI:
10.1080/19443994.2015.1069221
[28] H. A. Kazem and M. T. Chaichan, "Effect of humidity on photovoltaic
performance based on experimental study," International Journal of
Fig. 3 Visible light OFDM transmission model
Binary rate
data source
D/A
Converter
OFDM
Modulator
Training
Channel
Encoder
Assemble
OFDM
Symbol
QAM
Modulator
Pilots
interleaving
Transmitter
Optical Channel
A/D converter
Binary Data
OFDM
Demodulator
De-
Interleaving
Channel
Decoder
Frequency
Domain
Equalisation
Training Pilots
Synchronisation
Receiver

6. International Journal of Computation and Applied Sciences IJOCAAS, Volume2, Issue 2, April 2017, ISSN: 2399-450
56
Applied Engineering Research (IJAER), vol. 10, no. 23, pp. 43572-
43577, 2015.
[29] A. H. Al-Waeli, K. Sopian, H. A. Kazem and M. T. Chaichan,
"Photovoltaic solar thermal (PV/T) collectors past, present and future: a
review," International Journal of Applied Engineering Research, vol. 11,
no. 22, pp. 1075-10765, 2016.
[30] Наумейко И. В. Анализ псевдохаотического поведения
кейнсианских моделей экономики / И. В. Наумейко, Р. Дж. Аль-
Азави, В. А. Альрефаи // Вестник национального технического
университета «ХПИ». – 2013. – № 26. – С. 59–64.
[31] H. A. Kazem, J. H. Yousif, M. T. Chaichan, "Modeling of daily solar
energy system prediction using support vector machine for Oman,"
International Journal of Applied Engineering Research, vol. 11, no. 20,
pp. 10166-10172, 2016.
[32] H. M. S. Al-Maamary, H. A. Kazem and M. T. Chaichan, "Changing the
energy profile of the GCC States: a review," International Journal of
Applied Engineering Research (IJAER), vol. 11, no. 3, pp. 1980-1988,
2016.
[33] M. T. Chaichan, K. I. Abaas, "Performance amelioration of a Trombe
wall by using phase change material (PCM)," International Advanced
Research Journal in Science, Engineering and Technology, vol. 2, no. 4,
pp. 1-6, 2015.
[34] M. T. Chaichan, A. H. Al-Hamdani, A. M. Kasem, "Enhancing a
Trombe wall charging and discharging processes by adding nano-Al2O3
to phase change materials," International Journal of Scientific &
Engineering Research, vol. 7, no. 3, pp. 736-741, 2016.
[35] Аль-Азави, Р. Дж. Моделирование Человеко-Машинных Систем
восстановления в критических ситуациях с помощью процессов
гибели и размножения / Р. Дж. Аль-Азави // Материлы XVII-го
Международного молодежного форума «Радиоэлектроника и
молодежь в ХХІ Веке» – Том 7, 2013. – С. 92–93.
[36] Chaichan M T & Abaas Kh I, Practical investigation for improving
concentrating solar power stations efficiency in Iraqi weathers, Anbar J
for Engineering Science, vol.5, No. 1, pp: 76-87, 2012.
[37] M. T. Chaichan, K. I. Abaas, H. A. Kazem, H. S. Al Jibori & AU. bdul
Hussain, "Novel design of solar receiver in concentrated power system",
International J. of Multidispl. Research & Advcs. in Eng. (IJMRAE),
vol. 5, No. 1, pp: 211-226, 2013.
[38] A. H. A. Al-Waeli, A. S. A. Al-Mamari, A. H. K. Al-Kabi, M. T.
Chaichan, H. A. Kazem, "Evaluation of the economic and
environmental aspects of using photovoltaic water pumping system," 9th
International Conference on Robotic, Vision, Signal Processing &
Power Applications, Malaysia, 2016.
Dr. Hussam Dheaa Kamel was born in
Baghdad, Iraq, in 1986. He received the B.S. degree in
Computer communications Engineering form Al-
Rafidain University College, in 2008, MSc degree in
Telecommunication and Network Engineering from
Kharkiv National University of radio electronics
(KNURE), in 2010 and the Ph.D. degree in
Telecommunication and Network Engineering, from Kharkiv National
University of Radio electronics (KNURE), in 2013. His research interests are
Wireless Communications, MIMO, WiMAX, LTE, Visible Light
Communication, Control System, and Wireless sensor networks
Hadi Jameel was born in Baghdad, Iraq in 1988. He
received BSc degree from electrical engineering
department, Al Mustansiriya University, Iraq in 2010.
Received MSc degree from Electronic and
communication engineering in Al Mustansiriya
University, Iraq in 2013. His research interests are
Antenna, Wireless Communications, and Radar, Control System, and Wireless
sensor networks.