BPSK Subcarrier Intensity Modulated Free-Space Optical Communications in Atmospheric Turbulence Wasiu O. Popoola, Student Member, IEEE, and Zabih Ghassemlooy, Senior Member, IEEE

BPSK Subcarrier Intensity Modulated Free-Space
Optical Communications in Atmospheric Turbulence
Wasiu O. Popoola, Student Member, IEEE, and Zabih Ghassemlooy, Senior Member, IEEE




Abstract—Free-space optical communications (FSO) propagated
over a clear atmosphere suffers from irradiance fluctuation
caused by small but random atmospheric temperature fluctuations.
This results in decreased signal-to-noise ratio (SNR) and
consequently impaired performance. In this paper, the error
performance of the FSO using a subcarrier intensity modulation
(SIM) based on a binary phase shift keying (BPSK) scheme in
a clear but turbulent atmosphere is presented. To evaluate the
system error performance in turbulence regimes from weak to
strong, the probability density function (pdf) of the received
irradiance after traversing the atmosphere is modelled using the
gamma-gamma distribution while the negative exponential distribution
is used to model turbulence in the saturation region and
beyond. The effect of turbulence induced irradiance fluctuation
is mitigated using spatial diversity at the receiver. With reference
to the single photodetector case, up to 12 dB gain in the electrical
SNR is predicted with two direct detection PIN photodetectors in
strong atmospheric turbulence



for full paper mail me

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Average Symbol Error Probability of General-Order Rectangular Quadrature Amplitude Modulation of Optical Wireless Communication Systems Over Atmospheric Turbulence Channels

Average Symbol Error Probability of General-Order Rectangular Quadrature Amplitude Modulation of Optical Wireless Communication Systems Over Atmospheric Turbulence Channels


Abstract—Using an accurate exponential bound for
the Gaussian Q-function, we derive simple approximate
closed-form expressions for the average symbol
error probability (ASEP) of a free-space optical communication
link using subcarrier intensity modulation
(SIM) with general-order rectangular quadrature
amplitude modulation (QAM) over atmospheric
turbulence channels. To model the atmospheric turbulence
conditions, the log-normal and the gammagamma
distribution are used. Extensive numerical
and computer simulation results are presented in order
to verify the accuracy of the proposed mathematical
analysis.

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Performance Analysis of a Laser Ground-Station-to-Satellite Link With Modulated Gamma-Distributed Irradiance Fluctuations

Performance Analysis of a Laser
Ground-Station-to-Satellite Link With
Modulated Gamma-Distributed
Irradiance Fluctuations






Abstract—The performance of a ground-station-to-space

laser uplink with a Gaussian-beam wave model subject to

turbulence and beam wander effects is the topic of the

present study. The modulated gamma distribution is used to

describe the combined effect of the above two deteriorating

factors. At first, a versatile expression of the above probability

density function is deduced. We then derive novel closedform

expressions for its cumulative distribution function

and the moment-generating function. The scintillation index

and the probability of fade are hence readily evaluated. The

analysis is completed with the evaluation of the bit error

rate assuming heterodyne detection with differential phaseshift

keying. In order to attain an adequate error rate target,

we incorporate diversity at the satellite receiver. A proper

simulation scenario is adopted, and numerical results are

provided to verify the accuracy of the derived expressions.

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Free-Space Optical Communication Through Atmospheric Turbulence Channels

Free-Space Optical Communication Through
Atmospheric Turbulence Channels




Abstract—In free-space optical communication links, atmospheric
turbulence causes fluctuations in both the intensity and
the phase of the received light signal, impairing link performance.
In this paper, we describe several communication techniques to
mitigate turbulence-induced intensity fluctuations, i.e., signal
fading. These techniques are applicable in the regime in which the
receiver aperture is smaller than the correlation length of fading
and the observation interval is shorter than the correlation time
of fading. We assume that the receiver has no knowledge of the
instantaneous fading state. When the receiver knows only the
marginal statistics of the fading, a symbol-by-symbol ML detector
can be used to improve detection performance. If the receiver
has knowledge of the joint temporal statistics of the fading, maximum-
likelihood sequence detection (MLSD) can be employed,
yielding a further performance improvement, but at the cost of
very high complexity. Spatial diversity reception with multiple
receivers can also be used to overcome turbulence-induced fading.
We describe the use of ML detection in spatial diversity reception
to reduce the diversity gain penalty caused by correlation between
the fading at different receivers. In a companion paper, we
describe two reduced-complexity implementations of the MLSD,
which make use of a single-step Markov chain model for the
fading correlation in conjunction with per-survivor processing.
Index Terms—Atmospheric turbulence, free-space optical

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Performance Analysis of Decode-and-Forward Relaying in Gamma-Gamma Fading Channels

Performance Analysis of Decode-and-Forward
Relaying in Gamma-Gamma Fading Channels

Manav R. Bhatnagar, Member, IEEE

Abstract—We analyze performance of the decode-and-forward
(DF) protocol in the free space optical (FSO) links following
the Gamma-Gamma distribution. The cumulative distribution
function (cdf) and probability density function (pdf) of a random
variable containing mixture of the Gamma-Gamma and Gaussian
random variables is derived. By using the derived cdf and pdf,
average bit error rate of the DF relaying is obtained.

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Average BER Analysis of Differential Modulation in DF Cooperative Communication System over Gamma-Gamma Fading FSO Links

Average BER Analysis of Differential Modulation in DF Cooperative
Communication System over Gamma-Gamma Fading FSO Links

Manav R. Bhatnagar, Member, IEEE

Abstract—In this letter, we study differential modulation for decode-and-forward (DF) based free space optical (FSO) cooperative communication system over Gamma-Gamma fading channels. We derive exact bit error rate (BER) of the differential DF FSO system in terms of power series. The diversity order

and coding gain of the differentially modulated DF FSO system are analytically obtained. It is demonstrated by analysis and simulation that the differential DF FSO system is able to achieve significant performance gain over a non-cooperative direct transmission based differential FSO system.

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IEEE papers A COHERENT FREE SPACE OPTICAL LINK FOR LONG DISTANCE CLOCK COMPARISION, NAVIGATION, AND COMMUNICATION: THE MINI-DOLL PROJECT

A COHERENT FREE SPACE OPTICAL LINK FOR LONG DISTANCE CLOCK
COMPARISON, NAVIGATION, AND COMMUNICATION:
THE MINI-DOLL PROJECT

ABSTRACT

We describe the realization of a 5 km free space coherent optical link through the turbulent atmosphere between 

a telescope and a ground target. We present the phase noise of the link, limited mainly by atmospheric 

turbulence and mechanical vibrations of the telescope and the target. We discuss the implications of our results 

for applications, with particular emphasis on optical Doppler ranging to satellites and long distance frequency 

transfer.

For full paper mail me to kamalakannanmsajce@gmail.com

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IEEE Papers on fiber optical communication ATMOSPHERIC CHANNEL EFFECTS ON TERRESTRIAL FREE SPACE OPTICAL COMMUNICATION LINKS

ATMOSPHERIC CHANNEL EFFECTS ONTERRESTRIAL FREE SPACE OPTICALCOMMUNICATION LINKS

Abstract.

This paper illustrates the challenges imposed by the

atmospheric channel on the design of a terrestrial laser communication link.

The power loss due to scattering effect is described using the Kim/Kruse

scattering model while the effect and the penalty imposed by atmospheric

turbulence is highlighted by considering the bit error rate (BER) of an On-

Off Keying modulated link in an optical Poisson channel. The power loss due

to thick fog can measure over 100 dB/km while snow and rain result in much

lower attenuation. We show that non-uniformity in the atmospheric

temperature also contributes to performance deterioration due to

scintillation effect. At a BER of 10-4, for a channel with a turbulence strength

of >0.1, the penalty imposed by turbulence induced fading is over 20

photoelectron counts in order to achieve the same level of performance as a

channel with no fading. The work reported here is part of the EU COST

actions and EU projects

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ieee papers

The Design and Implementation of Remote Real Time Monitor System for Embedded 
Devices Based on GPRS 

ABSTRACT

We develop a remote monitoring system on environmental quality of Heihe river basin. The system consists of client and server, client is responsible for collecting data. We use multi-thread approach to develop server software, realizing online monitoring of sensor device, data management and log management and so on. Server uses Socket programming to communicate with client, the system has been running on the server.

LINK

http://ieeexplore.ieee.org/xpl/articleDetails.jsp;jsessionid=pL2PPYRV0FJ8KHcn5cFzxhdDLL41GGzB82vY0tVyvxM3hdpBLHPh!-2011277867?arnumber=6187990&contentType=Conference+Publications

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ieee papers

Power and safety management of electrical appliances in a smart power distribution 
system Using RFID

ABSTRACT

This paper introduces a low-cost solution to the on/off control of home appliances using a new power distribution system, and discusses how the system contributes to the safe and convenient use of the appliances. In the proposed system, with an RFID tag in the plug and newly-designed sockets/power strips, the smart meter identifies appliances connected to individual (wall) sockets simply by connecting the appliances to the socket. 

LINK

http://ieeexplore.ieee.org/xpl/login.jsp?tp=&arnumber=5722711&url=http%3A%2F%2Fieeexplore.ieee.org%2Fxpls%2Fabs_all.jsp%3Farnumber%3D5722711

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ieee papers for project(vlsi & es)

1     A low-power low-noise CMOS analog front-end IC for portable brain-heart Monitoring applications

Abstract

In this paper, a low power and low noise eight-channel analog front-end (AFE) IC for portable brain-heart monitoring applications is presented. The developed IC features a fully integrated eight-channel design which includes one channel for diffuse optical tomography (DOT), three channels for electrocardiography (ECG), and four channels for electroencephalography (EEG). In order to achieve the targets of lower power, lower noise, and more efficient area utilization, a new programmable readout channel is invented which is composed of a chopper-stabilized differential difference amplifier (CHDDA), an adjustable gain amplifier, and an adjustable low pass filter (LPF). Furthermore, a 10-bit successive approximation register analog-to-digital converter (SAR-ADC) is employed in conjunction with an analog multiplexer to select a particular biosignal for analog-to-digital conversion. The proposed IC has been fabricated in the TSMC 0.18 um CMOS technology and simulated using HSPICE under a 1.8-V supply voltage and an operating frequency of 512 Hz. The power supply rejection ratio (PSRR) +/- of the CHDDA is 113/105 dB. The power consumption of the programmable readout channel and the SAR-ADC is about 71.159 μW and 8.27 μW, respectively. The total power consumption of the full AFE chip is about 506.38 μW and the chip area is about 1733 × 1733 um².

           Paper Link :                    http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=5754151&contentType=Conference+Publications&ranges%3D2011_2012_p_Publication_Year%26matchBoolean%3Dtrue%26searchField%3DSearch_All%26queryText%3D%28%28hspice%29+AND+Low+power%29

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ieee papers for project(vlsi & es)

A Novel Design and Simulation of a Compact and Ultra Fast CNTFET Multi-valued Inverter Using HSPICE

Abstract

This paper presents a novel design of a compact multi-valued inverter circuit using Carbon Nanotube Field effect Transistor (CNTFET). All simulations are done by using HSPICE model of CNTFET. The novelty of this paper is by using only one circuit all multi-valued output can be achieved than using three different CNTFET circuits or complex band-gap reference circuits to produce each reference voltage for precise output in case of CMOS implementation which are previously done. Also the same design implementation using MOSFETs with different threshold mask would increase higher process cost. It is widely considered that CNTFET possesses high fabrication feasibility and superior device performance than MOSFET. The extensive simulated results and performance bench-marking of the proposed design also show a significant reduction in power delay product (PDP) which aids over 50% faster speed than typical multi-valued inverter. Hence with this uniquely new design it is possible to accomplish simplicity, energy efficiency and of course reducing the chip area in modern ultra low power VLSI circuits.



Paper Link : http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=6205527&contentType=Conference+Publications&ranges%3D2011_2012_p_Publication_Year%26matchBoolean%3Dtrue%26searchField%3DSearch_All%26queryText%3D%28%28%28VLSI%29+AND+Low+power%29+AND+hspice%29

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vlsi & embedded based ieee paper

http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=6182370&contentType=Conference+Publications&ranges%3D2011_2012_p_Publication_Year%26queryText%3Dembedded+system

http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=5953878&contentType=Conference+Publications&ranges%3D2010_2012_p_Publication_Year%26pageNumber%3D2%26queryText%3Dembedded+system+application

http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=6042512&contentType=Conference+Publications&ranges%3D2011_2012_p_Publication_Year%26pageNumber%3D2%26queryText%3Dembedded+system+application

http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=6037916&contentType=Conference+Publications&ranges%3D2011_2012_p_Publication_Year%26pageNumber%3D2%26queryText%3Dembedded+system+application

http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=6150551&contentType=Conference+Publications&ranges%3D2011_2012_p_Publication_Year%26pageNumber%3D3%26queryText%3Dembedded+system+application

http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=5770784&contentType=Conference+Publications&ranges%3D2011_2012_p_Publication_Year%26pageNumber%3D3%26queryText%3Dembedded+system+application

http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=5777390&contentType=Conference+Publications&ranges%3D2011_2012_p_Publication_Year%26pageNumber%3D3%26queryText%3Dembedded+system+application

http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=5973881&contentType=Conference+Publications&ranges%3D2011_2012_p_Publication_Year%26pageNumber%3D5%26queryText%3Dembedded+system+application

http://ieeexplore.ieee.org/xpl/articleDetails.jsp?tp=&arnumber=6177114&contentType=Conference+Publications&ranges%3D2011_2012_p_Publication_Year%26pageNumber%3D5%26queryText%3Dembedded+system+application

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Bus Data Acquisition and Romote Monitoring System Based on CAN Bus and GPRS

Abstract—Recently, attentions are focused more on bus interior
network application and the wireless bus-carry data transmission
technology. For developing a remote monitoring system, three
aspects of the system are discussed: the vehicle interior network
configuration, the CAN/GPRS gateway realization and the remote
monitoring server design. Described in the paper are the hardware
and software design of the system, designing of bus interior network
and the CAN/GPRS protocol conversion. Contents include GPRS
wireless networking and remote monitoring.

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