International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
FUZZY-CONTROLLED POWER-AWARE PROACTIVE-ACKNOWLEDGEMENT BASED BROADCASTING (FP...cscpconf
Network-wide broadcasting is a fundamental operation for mobile ad hoc networks. Inbroadcasting, a source node sends a message to all other nodes in the network. Under ordinary
flooding procedure, each node transmits the broadcast message to all of its 1-hop downlinkneighbours, i.e. all nodes residing within its radio-range. Receiving the broadcast message all those downlink neighbours reply with an acknowledgement. Since in an ad hoc network a node
may have multiple uplink neighbours, in ordinary flooding procedure, a node is supposed to receive the broadcast message from all those uplink neighbours and send acknowledgement to all of them, generating huge message contention and collision. This is popularly referred to as
the broadcast storm problem. The present article is focused to remove the broadcast redundancy within 2-hop neighbourhood and beyond, as much as possible by prioritizing the 1-
hop downlink neighbours of a node. Priority of a 1-hop downlink neighbour of a node ni increases if it is equipped with a large number of 1-hop downlink neighbours, large radiorange,
high remaining battery power and very small number of uplink neighbours closer to the broadcast source than ni
. ni waits a predefined amount of time to receive proactive
acknowledgements from the 1-hop downlink neighbours having less priority. If it does not receive acknowledgement from those downlink neighbours within the waiting time, it sends the
broadcast message to them. A fuzzy controller named Priority Assignor (PA) is embedded in every node that determines the priority of a 1-hop downlink neighbour. Simulation results firmly
establish that the proposed protocol FP2 B produces high broadcast delivery ratio at muchlesser message cost, compared to other state-of-the-art broadcast algorithms.
Optimal Transmit Power and Packet Size in Wireless Sensor Networks in Shadowe...IDES Editor
This paper investigates the effects of
shadowing on the optimal transmit power required to
sustain the network connectivity while maintaining a
predefined maximum tolerable Bit Error Rate (BER) in
a Wireless Sensor Networks (WSN). Optimization of
transmit power is of great importance in WSN since
sensor nodes are battery driven and optimization helps
to increase battery life by reducing inter node
interference significantly. An infinite Automatic Repeat
Request (ARQ) model has been considered to assess the
impact of shadowing and other network conditions on
energy requirement for successful packet transmission in
WSN. We also find the optimal packet length based on
energy efficiency. Effects of shadowing on optimal packet
size and energy efficiency in packetized data
transmission are also investigated. Further energy
consumption is minimized considering a variable packet
length based transmission. Use of optimal packet size
shows a significant reduction in energy spending.
Simulation of Direct Sequence Spread Spectrum for Wireless Communication Syst...ijtsrd
In this work, a simulation model for Direct Sequence Spread Spectrum (DSSS) scheme for wireless communication systems has been proposed. Unlike the case of a single frequency carrier, the modulated signal in DSSS occupies a much wider bandwidth in order to reduce the possible interferences with narrow band communication signals. In telecommunications, DSSS is a spread spectrum modulation technique used to reduce overall signal interference. The spreading of this signal makes the resulting wideband channel more noisy, allowing for greater resistance to unintentional and intentional interference. Y.V.S Durga Prasad | K. Venkateswarlu"Simulation of Direct Sequence Spread Spectrum for Wireless Communication Systems using Simulink" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-4 , June 2018, URL: http://www.ijtsrd.com/papers/ijtsrd14118.pdf http://www.ijtsrd.com/engineering/electronics-and-communication-engineering/14118/simulation-of-direct-sequence-spread-spectrum-for-wireless-communication-systems-using-simulink/yvs-durga-prasad
Communication by Whispers Paradigm for Short Range Communication in Cognitive...IDES Editor
With ever increasing demand for efficiency
and increased throughput over the wireless domain, we
have now reached a point where in a method for efficient
utilization of the electromagnetic spectrum is in demand.
Cognitive radio provides us with a way in which this demand
could be catered, it does so by using devices which
autonomously adjust their communication parameters to
adapt to the external environment. However, the most
critical of this entire technology is the parameter relating to
the Spectrum Sensing aspects. In order for cognitive radio
devices to properly configure and identify the presence of
a primary carrier in a communication mode, spectrum
sensors and efficient sensing algorithms are required. There
have been many algo- rithms developed in this field.
However, these available spectrum sensing algorithms are
prohibitively expensive to implement in wireless devices that
cater to only short distance communication. In this paper,
we propose a parsimonious spectrum sensing algorithm
which would deal with sensing and couple them with short
distance wireless devices over WiFi networks operating in the
2.4 GHz band. The efficiency parameters are also shown
using demonstrations.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Here we study the channel capacity of the signal from analog and digital communication signals. Also study data rates limit , Noisy-channel coding theorem, Shannon capacity theorem.
FUZZY-CONTROLLED POWER-AWARE PROACTIVE-ACKNOWLEDGEMENT BASED BROADCASTING (FP...cscpconf
Network-wide broadcasting is a fundamental operation for mobile ad hoc networks. Inbroadcasting, a source node sends a message to all other nodes in the network. Under ordinary
flooding procedure, each node transmits the broadcast message to all of its 1-hop downlinkneighbours, i.e. all nodes residing within its radio-range. Receiving the broadcast message all those downlink neighbours reply with an acknowledgement. Since in an ad hoc network a node
may have multiple uplink neighbours, in ordinary flooding procedure, a node is supposed to receive the broadcast message from all those uplink neighbours and send acknowledgement to all of them, generating huge message contention and collision. This is popularly referred to as
the broadcast storm problem. The present article is focused to remove the broadcast redundancy within 2-hop neighbourhood and beyond, as much as possible by prioritizing the 1-
hop downlink neighbours of a node. Priority of a 1-hop downlink neighbour of a node ni increases if it is equipped with a large number of 1-hop downlink neighbours, large radiorange,
high remaining battery power and very small number of uplink neighbours closer to the broadcast source than ni
. ni waits a predefined amount of time to receive proactive
acknowledgements from the 1-hop downlink neighbours having less priority. If it does not receive acknowledgement from those downlink neighbours within the waiting time, it sends the
broadcast message to them. A fuzzy controller named Priority Assignor (PA) is embedded in every node that determines the priority of a 1-hop downlink neighbour. Simulation results firmly
establish that the proposed protocol FP2 B produces high broadcast delivery ratio at muchlesser message cost, compared to other state-of-the-art broadcast algorithms.
Optimal Transmit Power and Packet Size in Wireless Sensor Networks in Shadowe...IDES Editor
This paper investigates the effects of
shadowing on the optimal transmit power required to
sustain the network connectivity while maintaining a
predefined maximum tolerable Bit Error Rate (BER) in
a Wireless Sensor Networks (WSN). Optimization of
transmit power is of great importance in WSN since
sensor nodes are battery driven and optimization helps
to increase battery life by reducing inter node
interference significantly. An infinite Automatic Repeat
Request (ARQ) model has been considered to assess the
impact of shadowing and other network conditions on
energy requirement for successful packet transmission in
WSN. We also find the optimal packet length based on
energy efficiency. Effects of shadowing on optimal packet
size and energy efficiency in packetized data
transmission are also investigated. Further energy
consumption is minimized considering a variable packet
length based transmission. Use of optimal packet size
shows a significant reduction in energy spending.
Simulation of Direct Sequence Spread Spectrum for Wireless Communication Syst...ijtsrd
In this work, a simulation model for Direct Sequence Spread Spectrum (DSSS) scheme for wireless communication systems has been proposed. Unlike the case of a single frequency carrier, the modulated signal in DSSS occupies a much wider bandwidth in order to reduce the possible interferences with narrow band communication signals. In telecommunications, DSSS is a spread spectrum modulation technique used to reduce overall signal interference. The spreading of this signal makes the resulting wideband channel more noisy, allowing for greater resistance to unintentional and intentional interference. Y.V.S Durga Prasad | K. Venkateswarlu"Simulation of Direct Sequence Spread Spectrum for Wireless Communication Systems using Simulink" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-4 , June 2018, URL: http://www.ijtsrd.com/papers/ijtsrd14118.pdf http://www.ijtsrd.com/engineering/electronics-and-communication-engineering/14118/simulation-of-direct-sequence-spread-spectrum-for-wireless-communication-systems-using-simulink/yvs-durga-prasad
Communication by Whispers Paradigm for Short Range Communication in Cognitive...IDES Editor
With ever increasing demand for efficiency
and increased throughput over the wireless domain, we
have now reached a point where in a method for efficient
utilization of the electromagnetic spectrum is in demand.
Cognitive radio provides us with a way in which this demand
could be catered, it does so by using devices which
autonomously adjust their communication parameters to
adapt to the external environment. However, the most
critical of this entire technology is the parameter relating to
the Spectrum Sensing aspects. In order for cognitive radio
devices to properly configure and identify the presence of
a primary carrier in a communication mode, spectrum
sensors and efficient sensing algorithms are required. There
have been many algo- rithms developed in this field.
However, these available spectrum sensing algorithms are
prohibitively expensive to implement in wireless devices that
cater to only short distance communication. In this paper,
we propose a parsimonious spectrum sensing algorithm
which would deal with sensing and couple them with short
distance wireless devices over WiFi networks operating in the
2.4 GHz band. The efficiency parameters are also shown
using demonstrations.
IJERA (International journal of Engineering Research and Applications) is International online, ... peer reviewed journal. For more detail or submit your article, please visit www.ijera.com
Here we study the channel capacity of the signal from analog and digital communication signals. Also study data rates limit , Noisy-channel coding theorem, Shannon capacity theorem.
Narrowband Spectrum Sensing for Different Fading Channels for Cognitive Radio...IJMERJOURNAL
Abstract: Nowadays the demand of applications of wireless communication has increased rapidly which causes the scarcity of radio spectrum. To empower future wireless communication services, the radio spectrum management is a very important factor. Cognitiveradio is a promising technology which provides an innovative way to improve utilization efficiency of available electromagnetic spectrum by sensing spectrum and shares it without harmful interference to other users. Narrowband spectrum sensing is the technique where the bandwidth of active primary transmitter in the vicinity of cognitive radio is less than the coherence bandwidth of channel. Fading is one of the greatest impairment of narrowband spectrum sensing. It is deflection of the attenuation. It influences a signal over certain propagation media.A communication channel that experiences fading isknown as fading channel. The effects of fading can be reduced by several fading models. In this paper, performanceanalysis of several realistic fading models on narrowband channel using energy detection method is employed. Finally, performance comparison of various fading models is guaranteed through simulation.
Approximation of Gaussian derivatives for UWB communicationijsrd.com
UWB is a new interesting technology for wireless communications. It can replace traditionally carrier-based radio transmission by pulse-based transmission using ultrawide band frequency but at a very low energy. An important aspect of research in this domain is to find a pulse with an optimal shape, whose power spectral density respects and best fits emission limitation mask imposed by FCC. In this paper we review common used Gaussian pulses and its derivatives and the influence of shape factor, finding an optimal specific value for each derivative. Next, we search to obtain possible better pulse shapes as linear combinations of Gaussian derivatives. Older studies refer in one case to the same shape factor for all derivatives and in other case to higher factor for first derivative and smaller shape factors for subsequent derivatives. Our new idea is to use Gaussian derivatives, each with its specific optimal shape factor and to use a "trial and error" algorithm to obtain a linear combination pulse with better performance.
Performance analysis on the basis of a comparative study between multipath ra...ijmnct
Interference is the most important issue for present wireless communication. There are various kinds of
channel used in wireless communication. Here I want to show a performance analysis on the basis of two
different channels – AWGN and Multipath Rayleigh fading channel. This is the comparative analysis with
different kinds of modulation techniques. Here I have also measured the Bit Error Rate with respect to
different modulation techniques and compare the rate in different channels. My objective is to compare the
different characteristics of the transmitter and receiver for different types of channels and modulators.
3 S W 2009 I E E E Abstracts Java, N C C T Chennaincct
final Year Projects, Final Year Projects in Chennai, Software Projects, Embedded Projects, Microcontrollers Projects, DSP Projects, VLSI Projects, Matlab Projects, Java Projects, .NET Projects, IEEE Projects, IEEE 2009 Projects, IEEE 2009 Projects, Software, IEEE 2009 Projects, Embedded, Software IEEE 2009 Projects, Embedded IEEE 2009 Projects, Final Year Project Titles, Final Year Project Reports, Final Year Project Review, Robotics Projects, Mechanical Projects, Electrical Projects, Power Electronics Projects, Power System Projects, Model Projects, Java Projects, J2EE Projects, Engineering Projects, Student Projects, Engineering College Projects, MCA Projects, BE Projects, BTech Projects, ME Projects, MTech Projects, Wireless Networks Projects, Network Security Projects, Networking Projects, final year projects, ieee projects, student projects, college projects, ieee projects in chennai, java projects, software ieee projects, embedded ieee projects, "ieee2009projects", "final year projects", "ieee projects", "Engineering Projects", "Final Year Projects in Chennai", "Final year Projects at Chennai", Java Projects, ASP.NET Projects, VB.NET Projects, C# Projects, Visual C++ Projects, Matlab Projects, NS2 Projects, C Projects, Microcontroller Projects, ATMEL Projects, PIC Projects, ARM Projects, DSP Projects, VLSI Projects, FPGA Projects, CPLD Projects, Power Electronics Projects, Electrical Projects, Robotics Projects, Solor Projects, MEMS Projects, J2EE Projects, J2ME Projects, AJAX Projects, Structs Projects, EJB Projects, Real Time Projects, Live Projects, Student Projects, Engineering Projects, MCA Projects, MBA Projects, College Projects, BE Projects, BTech Projects, ME Projects, MTech Projects, M.Sc Projects, Final Year Java Projects, Final Year ASP.NET Projects, Final Year VB.NET Projects, Final Year C# Projects, Final Year Visual C++ Projects, Final Year Matlab Projects, Final Year NS2 Projects, Final Year C Projects, Final Year Microcontroller Projects, Final Year ATMEL Projects, Final Year PIC Projects, Final Year ARM Projects, Final Year DSP Projects, Final Year VLSI Projects, Final Year FPGA Projects, Final Year CPLD Projects, Final Year Power Electronics Projects, Final Year Electrical Projects, Final Year Robotics Projects, Final Year Solor Projects, Final Year MEMS Projects, Final Year J2EE Projects, Final Year J2ME Projects, Final Year AJAX Projects, Final Year Structs Projects, Final Year EJB Projects, Final Year Real Time Projects, Final Year Live Projects, Final Year Student Projects, Final Year Engineering Projects, Final Year MCA Projects, Final Year MBA Projects, Final Year College Projects, Final Year BE Projects, Final Year BTech Projects, Final Year ME Projects, Final Year MTech Projects, Final Year M.Sc Projects, IEEE Java Projects, ASP.NET Projects, VB.NET Projects, C# Projects, Visual C++ Projects, Matlab Projects, NS2 Projects, C Projects, Microcontroller Projects, ATMEL Projects, PIC Projects, ARM Projects, DSP Projects, VLSI Projects, FPGA Projects, CPLD Projects, Power Electronics Projects, Electrical Projects, Robotics Projects, Solor Projects, MEMS Projects, J2EE Projects, J2ME Projects, AJAX Projects, Structs Projects, EJB Projects, Real Time Projects, Live Projects, Student Projects, Engineering Projects, MCA Projects, MBA Projects, College Projects, BE Projects, BTech Projects, ME Projects, MTech Projects, M.Sc Projects, IEEE 2009 Java Projects, IEEE 2009 ASP.NET Projects, IEEE 2009 VB.NET Projects, IEEE 2009 C# Projects, IEEE 2009 Visual C++ Projects, IEEE 2009 Matlab Projects, IEEE 2009 NS2 Projects, IEEE 2009 C Projects, IEEE 2009 Microcontroller Projects, IEEE 2009 ATMEL Projects, IEEE 2009 PIC Projects, IEEE 2009 ARM Projects, IEEE 2009 DSP Projects, IEEE 2009 VLSI Projects, IEEE 2009 FPGA Projects, IEEE 2009 CPLD Projects, IEEE 2009 Power Electronics Projects, IEEE 2009 Electrical Projects, IEEE 2009 Robotics Projects, IEEE 2009 Solor Projects, IEEE 2009 MEMS Projects, IEEE 2009 J2EE P
Satellite Telemetry Data Transmission Immunity from the ASI and Jamming Using...IOSRJECE
In the satellite telemetry command, controlling the power of the uplink signal, radiated away from the Earth to the spacecraft and downlink signal, radiated toward the Earth form the spacecraft is very important. The Uplink is transmitted at high power because of the unlimited power, while downlink should be controlled in power because of limited spacecraft power resources. This results in a lower Power Spectral Density (PSD) for the downlink and higher PSD for the uplink, which in many cases the uplink power due to be strong enough to reach the satellites at GEO would often also violate the PSD limits in the other orbits satellite telemetry signals like LEO. In addition due to long distance between the Earth and satellite, the received signals at the both terrestrial and transponder receivers are extremely week and strongly influenced by intentional interference (like jamming) or inadvertent interferences (such as the ASI). Spreading spectrum can solve the PSD problems for both directions but consumes a wide bandwidth. Fortunately, signals can be distinguished by using different spreading codes, allowing for CDMA. The Pseudo Noise (PN) spreading codes allow using many satellites or users (located in one satellite) the same frequency with overlapping signals simultaneously and also range measurement as useful ability to track the spacecraft in the space by the expanding value of the PN codes (Doppler Shift).[1] This paper specially considers to satellite telemetry data transmission immunity from the interference using Direct Sequence Spread Spectrum (DSSS) based on CDMA namely DS-CDMA (Direct Sequence-CDMA) by the unique properties correlation functions of the Gold and M-Sequence codes. Also the codes are examined in the fading channels, Reyleigh and AWGN, in terms of the BER vs. Eb/No to compare the practical results with theoretical values.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Investigation and Analysis of SNR Estimation in OFDM systemIOSR Journals
Estimation of signal to noise ratio (SNR) of received signal and to transmit the signal effectively for
the modern communication system. The performance of existing non-data-aided (NDA) SNR estimation methods
are substantially degraded for high level modulation scheme such as M-ary amplitude and phase shift keying
(APSK) or quadrature amplitude modulation (QAM).In this paper SNR estimation proposed method which uses
zero point auto-correlation of received signal per block and auto/cross- correlation of decision feedback signal
in orthogonal frequency division multiplexing (OFDM) system. Proposed method can be studied into two types;
Type 1 can estimate SNR by zero point auto-correlation of decision feedback signal based on the second
moment property. Type 2 uses both zero point auto-correlation and cross-correlation based on the fourth
moment property. In block-by-block reception of OFDM system, these two SNR estimation methods can be
possible for the practical implementation due to correlation based the estimation method and they show more
stable estimation performance than the earlier SNR estimation methods.
Broad-Spectrum Model for Sharing Analysis between IMTAdvanced Systems and FSS...IOSRJECE
An appraisal of orthogonal frequency division multiplexing (OFDM) accredited for IMT-Advanced has been well thought-out in this letter. Derivation of the power spectral density (PSD) produce new model which easily assess the interfering signal power that appears in the band of a victim system without a spectrum emission mask. Furthermore, the broad-spectrum investigative model (BIM) can assess the interference from the 4G systems into FSS systems, when transmit power is unallocated to some sub-carriers overlapping the band of the victim system. Closed form is derived to create the model.
A SIMULATION-BASED PERFORMANCE COMPARISON OF MANETS CDS CREATION ALGORITHMS U...csandit
Mobile Ad Hoc networks (MANETs) are gaining increased interest due to their wide range of
potential applications in civilian and military sectors. The self-control, self-organization,
topology dynamism, and bandwidth limitation of the wireless communication channel make
implementation of MANETs a challenging task. The Connected Dominating Set (CDS) has been
proposed to facilitate MANETs realization. Minimizing the CDS size has several advantages;
however, this minimization is NP complete problem; therefore, approximation algorithms are
used to tackle this problem. The fastest CDS creation algorithm is Wu and Li algorithm;
however, it generates a relatively high signaling overhead. Utilizing the location information of
network members reduces the signaling overhead of Wu and Li algorithm. In this paper, we
compare the performance of Wu and Li algorithm with its Location-Information-Based version
under two types of Medium Access Control protocols, and several network sizes. The MAC
protocols used are: a virtual ideal MAC protocol, and the IEEE 802.11 MAC protocol. The use
of a virtual ideal MAC enables us to investigate how the real-world performance of these
algorithms deviates from their ideal-conditions counterpart. The simulator used in this research
is the ns-2 network simulator.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
Narrowband Spectrum Sensing for Different Fading Channels for Cognitive Radio...IJMERJOURNAL
Abstract: Nowadays the demand of applications of wireless communication has increased rapidly which causes the scarcity of radio spectrum. To empower future wireless communication services, the radio spectrum management is a very important factor. Cognitiveradio is a promising technology which provides an innovative way to improve utilization efficiency of available electromagnetic spectrum by sensing spectrum and shares it without harmful interference to other users. Narrowband spectrum sensing is the technique where the bandwidth of active primary transmitter in the vicinity of cognitive radio is less than the coherence bandwidth of channel. Fading is one of the greatest impairment of narrowband spectrum sensing. It is deflection of the attenuation. It influences a signal over certain propagation media.A communication channel that experiences fading isknown as fading channel. The effects of fading can be reduced by several fading models. In this paper, performanceanalysis of several realistic fading models on narrowband channel using energy detection method is employed. Finally, performance comparison of various fading models is guaranteed through simulation.
Approximation of Gaussian derivatives for UWB communicationijsrd.com
UWB is a new interesting technology for wireless communications. It can replace traditionally carrier-based radio transmission by pulse-based transmission using ultrawide band frequency but at a very low energy. An important aspect of research in this domain is to find a pulse with an optimal shape, whose power spectral density respects and best fits emission limitation mask imposed by FCC. In this paper we review common used Gaussian pulses and its derivatives and the influence of shape factor, finding an optimal specific value for each derivative. Next, we search to obtain possible better pulse shapes as linear combinations of Gaussian derivatives. Older studies refer in one case to the same shape factor for all derivatives and in other case to higher factor for first derivative and smaller shape factors for subsequent derivatives. Our new idea is to use Gaussian derivatives, each with its specific optimal shape factor and to use a "trial and error" algorithm to obtain a linear combination pulse with better performance.
Performance analysis on the basis of a comparative study between multipath ra...ijmnct
Interference is the most important issue for present wireless communication. There are various kinds of
channel used in wireless communication. Here I want to show a performance analysis on the basis of two
different channels – AWGN and Multipath Rayleigh fading channel. This is the comparative analysis with
different kinds of modulation techniques. Here I have also measured the Bit Error Rate with respect to
different modulation techniques and compare the rate in different channels. My objective is to compare the
different characteristics of the transmitter and receiver for different types of channels and modulators.
3 S W 2009 I E E E Abstracts Java, N C C T Chennaincct
final Year Projects, Final Year Projects in Chennai, Software Projects, Embedded Projects, Microcontrollers Projects, DSP Projects, VLSI Projects, Matlab Projects, Java Projects, .NET Projects, IEEE Projects, IEEE 2009 Projects, IEEE 2009 Projects, Software, IEEE 2009 Projects, Embedded, Software IEEE 2009 Projects, Embedded IEEE 2009 Projects, Final Year Project Titles, Final Year Project Reports, Final Year Project Review, Robotics Projects, Mechanical Projects, Electrical Projects, Power Electronics Projects, Power System Projects, Model Projects, Java Projects, J2EE Projects, Engineering Projects, Student Projects, Engineering College Projects, MCA Projects, BE Projects, BTech Projects, ME Projects, MTech Projects, Wireless Networks Projects, Network Security Projects, Networking Projects, final year projects, ieee projects, student projects, college projects, ieee projects in chennai, java projects, software ieee projects, embedded ieee projects, "ieee2009projects", "final year projects", "ieee projects", "Engineering Projects", "Final Year Projects in Chennai", "Final year Projects at Chennai", Java Projects, ASP.NET Projects, VB.NET Projects, C# Projects, Visual C++ Projects, Matlab Projects, NS2 Projects, C Projects, Microcontroller Projects, ATMEL Projects, PIC Projects, ARM Projects, DSP Projects, VLSI Projects, FPGA Projects, CPLD Projects, Power Electronics Projects, Electrical Projects, Robotics Projects, Solor Projects, MEMS Projects, J2EE Projects, J2ME Projects, AJAX Projects, Structs Projects, EJB Projects, Real Time Projects, Live Projects, Student Projects, Engineering Projects, MCA Projects, MBA Projects, College Projects, BE Projects, BTech Projects, ME Projects, MTech Projects, M.Sc Projects, Final Year Java Projects, Final Year ASP.NET Projects, Final Year VB.NET Projects, Final Year C# Projects, Final Year Visual C++ Projects, Final Year Matlab Projects, Final Year NS2 Projects, Final Year C Projects, Final Year Microcontroller Projects, Final Year ATMEL Projects, Final Year PIC Projects, Final Year ARM Projects, Final Year DSP Projects, Final Year VLSI Projects, Final Year FPGA Projects, Final Year CPLD Projects, Final Year Power Electronics Projects, Final Year Electrical Projects, Final Year Robotics Projects, Final Year Solor Projects, Final Year MEMS Projects, Final Year J2EE Projects, Final Year J2ME Projects, Final Year AJAX Projects, Final Year Structs Projects, Final Year EJB Projects, Final Year Real Time Projects, Final Year Live Projects, Final Year Student Projects, Final Year Engineering Projects, Final Year MCA Projects, Final Year MBA Projects, Final Year College Projects, Final Year BE Projects, Final Year BTech Projects, Final Year ME Projects, Final Year MTech Projects, Final Year M.Sc Projects, IEEE Java Projects, ASP.NET Projects, VB.NET Projects, C# Projects, Visual C++ Projects, Matlab Projects, NS2 Projects, C Projects, Microcontroller Projects, ATMEL Projects, PIC Projects, ARM Projects, DSP Projects, VLSI Projects, FPGA Projects, CPLD Projects, Power Electronics Projects, Electrical Projects, Robotics Projects, Solor Projects, MEMS Projects, J2EE Projects, J2ME Projects, AJAX Projects, Structs Projects, EJB Projects, Real Time Projects, Live Projects, Student Projects, Engineering Projects, MCA Projects, MBA Projects, College Projects, BE Projects, BTech Projects, ME Projects, MTech Projects, M.Sc Projects, IEEE 2009 Java Projects, IEEE 2009 ASP.NET Projects, IEEE 2009 VB.NET Projects, IEEE 2009 C# Projects, IEEE 2009 Visual C++ Projects, IEEE 2009 Matlab Projects, IEEE 2009 NS2 Projects, IEEE 2009 C Projects, IEEE 2009 Microcontroller Projects, IEEE 2009 ATMEL Projects, IEEE 2009 PIC Projects, IEEE 2009 ARM Projects, IEEE 2009 DSP Projects, IEEE 2009 VLSI Projects, IEEE 2009 FPGA Projects, IEEE 2009 CPLD Projects, IEEE 2009 Power Electronics Projects, IEEE 2009 Electrical Projects, IEEE 2009 Robotics Projects, IEEE 2009 Solor Projects, IEEE 2009 MEMS Projects, IEEE 2009 J2EE P
Satellite Telemetry Data Transmission Immunity from the ASI and Jamming Using...IOSRJECE
In the satellite telemetry command, controlling the power of the uplink signal, radiated away from the Earth to the spacecraft and downlink signal, radiated toward the Earth form the spacecraft is very important. The Uplink is transmitted at high power because of the unlimited power, while downlink should be controlled in power because of limited spacecraft power resources. This results in a lower Power Spectral Density (PSD) for the downlink and higher PSD for the uplink, which in many cases the uplink power due to be strong enough to reach the satellites at GEO would often also violate the PSD limits in the other orbits satellite telemetry signals like LEO. In addition due to long distance between the Earth and satellite, the received signals at the both terrestrial and transponder receivers are extremely week and strongly influenced by intentional interference (like jamming) or inadvertent interferences (such as the ASI). Spreading spectrum can solve the PSD problems for both directions but consumes a wide bandwidth. Fortunately, signals can be distinguished by using different spreading codes, allowing for CDMA. The Pseudo Noise (PN) spreading codes allow using many satellites or users (located in one satellite) the same frequency with overlapping signals simultaneously and also range measurement as useful ability to track the spacecraft in the space by the expanding value of the PN codes (Doppler Shift).[1] This paper specially considers to satellite telemetry data transmission immunity from the interference using Direct Sequence Spread Spectrum (DSSS) based on CDMA namely DS-CDMA (Direct Sequence-CDMA) by the unique properties correlation functions of the Gold and M-Sequence codes. Also the codes are examined in the fading channels, Reyleigh and AWGN, in terms of the BER vs. Eb/No to compare the practical results with theoretical values.
IJRET : International Journal of Research in Engineering and Technology is an international peer reviewed, online journal published by eSAT Publishing House for the enhancement of research in various disciplines of Engineering and Technology. The aim and scope of the journal is to provide an academic medium and an important reference for the advancement and dissemination of research results that support high-level learning, teaching and research in the fields of Engineering and Technology. We bring together Scientists, Academician, Field Engineers, Scholars and Students of related fields of Engineering and Technology
Investigation and Analysis of SNR Estimation in OFDM systemIOSR Journals
Estimation of signal to noise ratio (SNR) of received signal and to transmit the signal effectively for
the modern communication system. The performance of existing non-data-aided (NDA) SNR estimation methods
are substantially degraded for high level modulation scheme such as M-ary amplitude and phase shift keying
(APSK) or quadrature amplitude modulation (QAM).In this paper SNR estimation proposed method which uses
zero point auto-correlation of received signal per block and auto/cross- correlation of decision feedback signal
in orthogonal frequency division multiplexing (OFDM) system. Proposed method can be studied into two types;
Type 1 can estimate SNR by zero point auto-correlation of decision feedback signal based on the second
moment property. Type 2 uses both zero point auto-correlation and cross-correlation based on the fourth
moment property. In block-by-block reception of OFDM system, these two SNR estimation methods can be
possible for the practical implementation due to correlation based the estimation method and they show more
stable estimation performance than the earlier SNR estimation methods.
Broad-Spectrum Model for Sharing Analysis between IMTAdvanced Systems and FSS...IOSRJECE
An appraisal of orthogonal frequency division multiplexing (OFDM) accredited for IMT-Advanced has been well thought-out in this letter. Derivation of the power spectral density (PSD) produce new model which easily assess the interfering signal power that appears in the band of a victim system without a spectrum emission mask. Furthermore, the broad-spectrum investigative model (BIM) can assess the interference from the 4G systems into FSS systems, when transmit power is unallocated to some sub-carriers overlapping the band of the victim system. Closed form is derived to create the model.
A SIMULATION-BASED PERFORMANCE COMPARISON OF MANETS CDS CREATION ALGORITHMS U...csandit
Mobile Ad Hoc networks (MANETs) are gaining increased interest due to their wide range of
potential applications in civilian and military sectors. The self-control, self-organization,
topology dynamism, and bandwidth limitation of the wireless communication channel make
implementation of MANETs a challenging task. The Connected Dominating Set (CDS) has been
proposed to facilitate MANETs realization. Minimizing the CDS size has several advantages;
however, this minimization is NP complete problem; therefore, approximation algorithms are
used to tackle this problem. The fastest CDS creation algorithm is Wu and Li algorithm;
however, it generates a relatively high signaling overhead. Utilizing the location information of
network members reduces the signaling overhead of Wu and Li algorithm. In this paper, we
compare the performance of Wu and Li algorithm with its Location-Information-Based version
under two types of Medium Access Control protocols, and several network sizes. The MAC
protocols used are: a virtual ideal MAC protocol, and the IEEE 802.11 MAC protocol. The use
of a virtual ideal MAC enables us to investigate how the real-world performance of these
algorithms deviates from their ideal-conditions counterpart. The simulator used in this research
is the ns-2 network simulator.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
International Journal of Engineering Research and Applications (IJERA) aims to cover the latest outstanding developments in the field of all Engineering Technologies & science.
International Journal of Engineering Research and Applications (IJERA) is a team of researchers not publication services or private publications running the journals for monetary benefits, we are association of scientists and academia who focus only on supporting authors who want to publish their work. The articles published in our journal can be accessed online, all the articles will be archived for real time access.
Our journal system primarily aims to bring out the research talent and the works done by sciaentists, academia, engineers, practitioners, scholars, post graduate students of engineering and science. This journal aims to cover the scientific research in a broader sense and not publishing a niche area of research facilitating researchers from various verticals to publish their papers. It is also aimed to provide a platform for the researchers to publish in a shorter of time, enabling them to continue further All articles published are freely available to scientific researchers in the Government agencies,educators and the general public. We are taking serious efforts to promote our journal across the globe in various ways, we are sure that our journal will act as a scientific platform for all researchers to publish their works online.
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Study and Analysis Capacity of MIMO Systems for AWGN Channel Model ScenariosIJERA Editor
Future wireless communication systems can utilize the spatial properties of the wireless channel to enhance the spectral efficiency and therefore increases its channel capacity. This can be designed by deploying multiple antennas at both the transmitter side and receiver side. The basic measure of performance is the capacity of a channel; the maximum rate of communication for which arbitrarily small error probability can be achieved. The AWGN (additive white Gaussian noise) channel introduces the notion of capacity through a heuristic argument. The AWGN channel is then used as a basic building block to check the capacity of wireless fading channels in contrast to the AWGN channel. There is no single definition of capacity for fading channels that is applicable in all situations. Several notions of capacity are developed, and together they form a systematic study of performance limits of fading channels. The various capacity measures allow us to observe clearly the various types of resources available in fading channels: degrees of freedom, power and diversity. The MIMO systems capacity can be enhanced linearly with large the number of antennas. This paper elaborates the study of MIMO system capacity using the AWGN Channel Model, Channel Capacity, Channel Fast Fading, Spatial Autocorrelation and Power delay profile for various channel environments.
In mmWave massive MIMO systems, the lens antenna array and beam selection by beamspace MIMO are employed to target the number of required RF chains reduced without obvious performance loss. For cost – effective, the number of RF chain is an allowable limitation, however, to obtain the near-optimal capacity efficiently, beam selection must require the exact information of the wide size of beamspace channel. Solution to this problem, in this paper we suggest analyzing whole beamspace based on maximal SINR. More specicfically, it is confirmed that the proposed beam selection algorithms achieve higher power efficiencies than a full system where all beams are employed.
In this paper, three beamforming design are considered for multi user MIMO system. First, transmit
beamformers are fixed and the receive (RX) beamformers are calculated. Transmit beamformer (TX-BF)is
projectedas a null space of appropriate channels. It reduces the interference for each user. Then the receiver
beamformer is determined which maximize the SNR. This beamforming design provides less computation time.
The second case is joint TX and RX beamformer for SNR maximization. In this transmitter and receiver
beamformer are calculated using extended alternating optimization (EAO) algorithm. The third one is joint
transmitter and receiver beamforming for SNR and SINR maximization using EAO algorithm. This algorithm
provides better error performance and sum rate performance. All the design cases are simulated by using
standard multipath channel model. Our simulation results illustrate that compared to the least square design and
zero forcing design, the joint TX and RX beamforming design using EAO algorithm provides faster
beamforming and improved error performance and sum rate.
International Journal of Engineering Research and Applications (IJERA) is an open access online peer reviewed international journal that publishes research and review articles in the fields of Computer Science, Neural Networks, Electrical Engineering, Software Engineering, Information Technology, Mechanical Engineering, Chemical Engineering, Plastic Engineering, Food Technology, Textile Engineering, Nano Technology & science, Power Electronics, Electronics & Communication Engineering, Computational mathematics, Image processing, Civil Engineering, Structural Engineering, Environmental Engineering, VLSI Testing & Low Power VLSI Design etc.
Capacity Enhancement of MIMO-OFDM System in Rayleigh Fading ChannelIOSR Journals
MIMO-OFDM system in Rayleigh Fading Channel is very popular technique for mobile
communication now a day’s for research. Here we want increase the capacity of MIMO-OFDM of system by
using adaptive modulation, Algebraic Space-Time Codes (ASTC) encoder for MIMO Systems are based on
quaternion algebras .we found that ergodic capacity has some limitation which reduce the system’s
performance to overcome this we use ASTC code . ASTC code are full rank, full rate and non vanishing constant
minimum determinant for increasing spectral efficiency and reducing Peak to Average Power Ratio (PAPR) .
Capacity Enhancement of MIMO-OFDM System in Rayleigh Fading ChannelIOSR Journals
Abstract: MIMO-OFDM system in Rayleigh Fading Channel is very popular technique for mobile communication now a day’s for research. Here we want increase the capacity of MIMO-OFDM of system by using adaptive modulation, Algebraic Space-Time Codes (ASTC) encoder for MIMO Systems are based on quaternion algebras .we found that ergodic capacity has some limitation which reduce the system’s performance to overcome this we use ASTC code . ASTC code are full rank, full rate and non vanishing constant minimum determinant for increasing spectral efficiency and reducing Peak to Average Power Ratio (PAPR) . Keywords— Adaptive modulation ASTC code, Capacity, BER, Ergodic capacity, PAPR, Spectral Efficiency and SNR
Bit Error Rate Performance of MIMO Spatial Multiplexing with MPSK Modulation ...ijsrd.com
Wireless communication is one of the most effective areas of technology development of our time. Wireless communications today covers a very wide array of applications. In this, we study the performance of general MIMO system, the general V-BLAST architecture with MPSK Modulation in Rayleigh fading channels. Based on bit error rate, we show the performance of the 2x2 schemes with MPSK Modulation in noisy environment. We also show the bit error rate performance of 2x2, 3x3, 4x4 systems with BPSK modulation. We see that the bit error rate performance of 2x2 systems with QPSK modulation gives us the best performance among other schemes analysed here.
Analysis of Space Time Codes Using Modulation TechniquesIOSR Journals
Abstract: In this Paper, Analysis of channel codes for improving the data rate and reliability of communication over fading channels using multiple transmit antennas has been considered. The codes, namely ’Space Time Codes’ render full diversity and amend coding gain. Performance criteria for designing such codes, under this assumption that the fading is slow and nonselective frequency, is also analysed. Under this research, Study of Frame Error Rate(FER) and outage capacity is compared for different no. Of transmit and receive antennas as well as for different modulation techniques. According to theoretical results FER decreases with increasing SNR and No. Of receiving antennas. Numerical and practical result shows that FER decreases with increasing SNR and no. Of receiving antennas. Keywords: Space time Block Codes ,Space time trellis Codes,Frame Error Rate(FER),Outage capacity,Pairwise Error Probability
New Adaptive Cooperative-MIMO for LTE Technologyijtsrd
Multiple Input Multiple Output (MIMO) systems have been widely used in an area of wireless cellular communication system, providing the both increased capacity and reliability. However, the use of multiple antennas in mobile terminals may not be very practical due to limited space and other implementation issues. In this paper, cooperative MIMO has been used in a way to optimise the implementation and working of conventional MIMO systems in terms of BER and Spectral Efficiency while maintaining a minimal number of antennas on each handset. Cooperative MIMO with V-BLAST transmission over Rayleigh flat fading channels and amplify and forward protocol with one relay node for modulation techniques like BPSK, QPSK, QAM using various decoding techniques has been analysed. Decoding algorithms like ZF, MMSE and ML have been analysed with respect to their BER performances. Since, there is throughput loss in cooperative MIMO due to extra resources required for relaying, adaptive modulation has been used with C-MIMO to meet the demands for high data rates in Long Term Evolution Network. Sukhreet Kaur | Dr. Amita Soni"New Adaptive Cooperative-MIMO for LTE Technology" Published in International Journal of Trend in Scientific Research and Development (ijtsrd), ISSN: 2456-6470, Volume-2 | Issue-4 , June 2018, URL: http://www.ijtsrd.com/papers/ijtsrd12919.pdf http://www.ijtsrd.com/engineering/electronics-and-communication-engineering/12919/new-adaptive-cooperative-mimo-for-lte-technology/sukhreet-kaur
In this paper, we analyzed a numerical evaluation of the performance of MIMO radio systems in the LTE network environment. Downlink physical layer of the OFDM-MIMO based radio interface is considered for system model and a theoretical analysis of the bit error rate of the two space-time codes (SFBC 2×1 and FSTD 4×2 codes are adopted by the LTE norm as a function of the signal to noise ratio. Analytical expressions are given for transmission over a Rayleigh channel without spatial correlation which is then compared with Monte-Carlo simulations. Further evaluated channel capacity and simulation results show throughput almost reaches to the capacity limit.
Ber analysis of 2x2 mimo spatial multiplexing under awgn and rician channels ...ijwmn
Multiple-input–multiple-output (MIMO) wireless systems use multiple antennas at transmitting and
receiving end to offer improved capacity and data rate over single antenna systems in multipath channels.
In this paper we have investigated the Spatial Multiplexing technique of MIMO systems. Here different
fading channels like AWGN and Rician are used for analysis purpose. Moreover we analyzed the technique
using high level modulations (i.e. M-PSK for different values of M). Detection algorithms used are Zero-
Forcing and Minimum mean square estimator. Performance is analyzed in terms of BER (bit error rate) vs.
SNR (signal to noise ratio).
A New Transmission Scheme for MIMO – OFDMijsrd.com
This contribution introduces a new transmission scheme for multiple-input multiple-output (MIMO) Orthogonal Frequency Division Multiplexing (OFDM) systems. The new scheme is efficient and suitable especially for symmetric channels such as the link between two base stations or between two antennas on radio beam transmission. This survey Paper presents the performance analysis of V-BLAST based multiple inputs multiple output orthogonal frequency division multiplexing (MIMO-OFDM) system with respect to bit error rate per signal to noise ratio (BER/SNR) for various detection techniques. A 2X2 MIMO-OFDM system is used for the performance evaluation. The simulation results shows that the performance of V-BLAST based detection techniques is much better than the conventional methods. Alamouti Space Time Block Code (STBC) scheme is used with orthogonal designs over multiple antennas which showed simulated results are identical to expected theoretical results. With this technique both Bit Error Rate (BER) and maximum diversity gain are achieved by increasing number of antennas on either side. This scheme is efficient in all the applications where system capacity is limited by multipath fading.
On limits of Wireless Communications in a Fading Environment: a General Param...ijeei-iaes
The reliable services along with high throughput can be achieved by using wireless communication systems. These systems also provides a wide coverage because of their features, no doubt MIMO Communication System [1] is one among them. Features provided by these systems ensure the improved system coverage and increased data transmission rate by considering multiple numbers of transmitter and receiver antennas. In this article, the concept of equalization has been considered and finally the performance of the MIMO Systems in Rician flat fading [5] channel is compared with the Rayleigh flat fading channel. It has also been observed that the performance of these Systems in Rician Flat Fading Channel is the best as compare to the Rayleigh Flat Fading Channel [10]. It has been concluded that the successive interference methods provide better performance as compare to others, but their complexity is high. Simulation results shows that ML provides the better performance in comparison to other equalizers but Sphere decoder provides the best performance.
Noise uncertainty effect on multi-channel cognitive radio networks IJECEIAES
Achieving high throughput is the most important goal of cognitive radio networks. The main process in cognitive radio is spectrum sensing that targets getting vacant channels. There are many sensing methods like matched filter, feature detection, interference temperature and energy detection which is employed in the proposed system; however, energy detection suffers from noise uncertainty. In this paper a study of throughput under noise fluctuation effect is introduced. The work in this paper proposes multi-channel system; the overall multi-channel throughput is studied under noise fluctuation effect. In addition, the proficiency of the network has been examined under different number of channels and sensing time with noise uncertainty.
To meet the demands of high speed required by mobile communication of past generations ,one solution is to increase the number of antennas to the show and the reception of the wireless link this is called MIMO (Multiple input ,Multiple output )technology .however ,the integration of multiple antennas on the same PCB is delicate because of the small volume that require some applications and electromagnetic antenna between the coupling ,phenomena that we cannot neglect them .indeed a strong isolation between them has been reached to reduce fading of the signal caused by the electromagnetic antenna reached to reduce fading of the signal caused by the electromagnetic coupling and maximize the overall gain .in this article we are interested then integration on the same printed circuit of eight antennas MIMO are not operation in the same frequency band .the first antenna of this last work at 2.4GHz .other antennas have resonance frequency folling each with 20MHz offset this device is characterized by its original form that keeps is highly isolated antennas from the point of view electromagnetic coupling
PHP Frameworks: I want to break free (IPC Berlin 2024)Ralf Eggert
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1. K. Rajesh et al Int. Journal of Engineering Research and Applications
ISSN : 2248-9622, Vol. 3, Issue 6, Nov-Dec 2013, pp.1831-1836
RESEARCH ARTICLE
www.ijera.com
OPEN ACCESS
Secure Communication in Low Snr Regime Over Fading
Channels in Mimo
K. Rajesh*, K. V. Lalitha Bhavani**
*M.Tech (Digital Electronics And Communication Systems) Student, AITAM College, Tekkali in India.
**Associate Professor in ECE Department, AITAM College, Tekkali in India.
ABSTRACT
In this work we consider MIMO fading channels and characterize the reliability function in the low-SNR
regime as a function of the number of transmit and receive antennas. For the case when the fading matrix H has
independent entries, we show that the number of transmit antennas plays a key role in reducing the peakiness in
the input signal required to achive the optimal error exponent for a given communication rate. Further by
considering a correlated channel model, we show that the maximum performance gain is achieved when the
entries of the channel fading matrix are fully correlated. The results we presented in this work in the low- SNR
regime can also be applied to the finite bandwidth regime.
Keywords: MIMO, Bandwidth Allocation, Fading, Low SNR
I.
INTRODUCTION
The use of multiple antennas at the
transmitter and receiver in wireless systems,
popularly known as MIMO (multiple-input
multiple-output) technology, has rapidly gained in
popularity over the past decade due to its powerful
performance-enhancing
capabilities.
Communication in wireless channels is impaired
predominantly by multi-path fading. Multi-path is
the arrival of the transmitted signal at an intended
receiver through differing angles and/or differing
time delays and/or differing frequency (i.e.,
Doppler) shifts due to the scattering of
electromagnetic waves in the environment.
Consequently, the received signal power fluctuates
in space (due to angle spread) and/or frequency
(due to delay spread) and/or time (due to Doppler
spread) through the random superposition of the
impinging multi-path components. This random
fluctuation in signal level, known as fading, can
severely affect the quality and reliability of
wireless
communication.
Additionally,
the
constraints posed by limited power and scarce
frequency bandwidth make the task of designing
high data rate, high reliability wireless
communication systems extremely challenging.
MIMO
technology
constitutes
a
breakthrough in wireless communication system
design. The technology offers a number of benefits
that help meet the challenges posed by both the
impairments in the wireless channel as well as
resource constraints. In addition to the time and
frequency dimensions that are exploited in
conventional single-antenna (single-input singleoutput) wireless systems, the leverages of MIMO
are realized by exploiting the spatial dimension
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(Provided by the multiple antennas at the
transmitter and the receiver).
The advantages of multiple-input multipleoutput (MIMO) systems have been widely
acknowledged, to the extent that certain transmit
diversity methods (i.e., Alamouti signaling) have
been incorporated into wireless standards.
Although transmit diversity is clearly advantageous
on a cellular base station, it may not be practical for
other scenarios. Specifically, due to size, cost, or
hardware limitations, a wireless agent may not be
able to support multiple transmit antennas.
Examples include most handsets (size) or the nodes
in a wireless sensor network (size, power).
Fig.1:secure communication system
We consider the secure transmission of
information over an ergodic fading channel in the
presence of an eavesdropper. Our eavesdropper can
be viewed as the wireless counterpart of Wyner's
wire tapper. The secrecy capacity of such a system
is characterized under the assumption of
asymptotically long coherence intervals. We first
consider the full channel state information (CSI)
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2. K. Rajesh et al Int. Journal of Engineering Research and Applications
ISSN : 2248-9622, Vol. 3, Issue 6, Nov-Dec 2013, pp.1831-1836
case, where the transmitter has access to the
channel gains of the legitimate receiver and the
eavesdropper. The secrecy capacity under this full
CSI assumption serves as an upper bound for the
secrecy capacity when only the CSI of the
legitimate receiver is known at the transmitter,
which is characterized next. In each scenario, the
perfect secrecy capacity is obtained along with the
optimal power and rate allocation strategies. We
then propose a low-complexity on/off power
allocation strategy that achieves near-optimal
performance with only the main channel CSI. More
specifically, this scheme is shown to be
asymptotically optimal as the average signal-tonoise ratio (SNR) goes to infinity, and
interestingly, is shown to attain the secrecy
capacity under the full CSI assumption. Overall,
channel fading has a positive impact on the secrecy
capacity and rate adaptation, based on the main
channel CSI, is critical in facilitating secure
communications over slow fading channels.
channel input-output relations between the
transmitter and legitimate receiver, and the
transmitter and eavesdropper are given by
ym = Hmx + nm , ye = Hex + ne ,
where, x denotes the nT ×1–dimensional
transmitted signal vector. nR×1–dimensional ym
and nE ×1–dimensional ye represent the received
signal vectors at the legitimate receiver and
eavesdropper, respectively. Moreover, nm with
dimension nR×1 and ne with dimension nE × 1 are
independent, zero-mean Gaussian random vectors.
The signal-to-noise ratio is defined as,
SNR
CHANNEL MODEL
P
nR N m
the channel models, Hm is the nR × nT –
dimensional channel matrix between the transmitter
and legitimate receiver, and He is the nE × nT –
dimensional channel matrix between the transmitter
and eavesdropper.
III.
II.
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SECRECY IN THE LOW-SNR
REGIME
The channel matrices Hm and He are fixed
for the entire transmission period and are known to
all three terminals. The assumption of perfect
channel knowledge can be justified in scenarios in
which a base station, which knows the channels of
the users, attempt to transmit confidential messages
to a user and hence treat the other users as
eavesdroppers.
In this paper, we concentrate on the lowSNR regime. In this regime, the behavior of the
secrecy capacity can be accurately predicted by its
first and second derivatives with respect to SNR at
SNR = 0:
Fig.2.Channel Model
MIMO is the use of multiple antennas at
both the transmitter and receiver to improve
communication performance. It is one of several
forms of smart antenna technology. Note that the
terms input and output refer to the radio channel
carrying the signal, not to the devices having
antennas. New techniques, which account for the
extra spatial dimension, have been adopted to
realize these gains in new and previously existing
systems.
MIMO technology has attracted attention
in wireless communications, because it offers
significant increases in data throughput and link
range without additional bandwidth or increased
transmit power. The use of multiple dimensions at
both ends of a communication link offers
significant improvements in terms of spectral
efficiency and link reliability.
We consider a MIMO channel model and
assume that the transmitter, legitimate receiver, and
eavesdropper are equipped with nT , nR, and nE
antennas, respectively. We further assume that the
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C (0)
C S ( SNR) C S (0) SNR
SNR 2 ( SNR 2 )
2
Eb
N 0s ,m in
log 2
C S ( 0)
2 CS (0)
S0
CS (0)
2
N0 s, min denotes the minimum bit energy required
for reliable communication under secrecy
constraints (or equivalently minimum energy per
secret bit), and S0 denotes the wideband slope
which is the slope of the secrecy capacity in
bits/dimension/(3 dB) at the point Eb /N0 s, min.
3.1.1 FIRST AND SECOND DERIVATIVES
OF THE SECRECY CAPACITY
We determine the first and second
derivatives of the secrecy capacity at SNR = 0, and
provide a second-order approximation to the
MIMO secrecy capacity in the low-SNR regime.
Through this analysis, we quantify the impact of
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3. K. Rajesh et al Int. Journal of Engineering Research and Applications
ISSN : 2248-9622, Vol. 3, Issue 6, Nov-Dec 2013, pp.1831-1836
secrecy constraints on the performance. We
identify the optimal transmission strategies in the
low-SNR regime. In particular, we determine that
transmission in the maximal-eigenvalue eigenspace
of a certain matrix that depends on the channel
matrices is second-order optimal. In the case in
which the maximum eigenvalue is distinct,
beamforming is shown to be optimal.
Secrecy rate expression given by
I S ( SNR)
1
nR
1
1
H m K x H m log det I
H e K x H
log det I
e
Nm
Ne
The first derivative of the secrecy capacity in with
respect to SNR at SNR = 0.
max( ) if max( ) 0
CS (0) max( )
0 else
In the absence of secrecy constraints, the first and
second derivatives of the MIMO capacity at SNR =
0.
C S (0) m ax ( H m H m )
and C (0) nR 2 ( H H )
max
m m
l
Where, l is the multiplicity of
m ax( H m H m )
Hence, the first and second derivatives are achieved
by transmitting in the maximal-eigenvalue
eigenspace of H†mHm, the subspace in which the
transmitter-receiver channel is the strongest.
If there are secrecy constraints, we should at low
SNRs transmit in the direction in which the
transmitter-receiver channel is strongest with
respect to the transmitter-eavesdropper channel
normalized by the ratio of the noise variances.
3.1.2. MINIMUM ENERGY PER SECRET BIT
In this section, we study the energy
required to send information both reliably and
securely. In particular, we investigate the minimum
energy required to send one secret bit. Before
identifying the minimum energy per secret bit, we
first show that the secrecy capacity is concave in
SNR. The secrecy capacity Cs achieved under the
average power constraint E{||x||2} ≤ P is a concave
function of SNR.
The energy per secret bit normalized by the noise
variance at the legitimate receiver is defined as
Eb
SNR
log 2
N 0 C S ( SNR)
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model. We see, as predicted, that the minimum bit
energy is attained in all cases as SNR and hence
rates approach zero. While the minimum bit energy
is Eb/N0=-6.01dB in the absence of secrecy
constraints, the minimum bit energy per secret bit
is Eb/N0 s,min=-3.71Db.
IV.
THE IMPACT OF FADING
Assume that the channel matrices Hm and
He are random matrices, whose components are
stationary and ergodic random variables, modeling
fading in wireless transmissions. We again assume
that realizations of these matrices are perfectly
known by all the terminals. As discussed fading
channel can be regarded as a set of parallel sub
channels each of which corresponds to a particular
fading realization. Hence, in each sub channel, the
channel matrices are fixed similarly as in the
channel model considered in the previous section.
It is shown that having independent inputs for each
sub channel is optimal and the secrecy capacity of
the set of parallel sub channels is equal to the sum
of the capacities of sub channels. Therefore, the
secrecy capacity of fading channels can be found
by averaging the secrecy capacities attained for
different fading realizations.
We assume that the transmitter is subject
to a short-term power constraint. Hence, for each
channel realization, the same amount of power is
used and we have tr (Kx) ≤ P. With this
assumption, the transmitter is allowed to perform
power adaptation in space across the antennas, but
not across time. Under such constraints, it can
easily be seen from the above discussion that the
average secrecy capacity in fading channels is
given by
𝑚𝑎𝑥
1
𝐾 𝑥≥0
𝐶𝑠 =
𝐸𝐻 𝑚 , 𝐻 𝑒
log det 𝐼
𝑛𝑅
𝑡𝑟 𝐾 𝑥 ≤ 𝑃
1
+
𝐻 𝐾 𝐻+
𝑁𝑚 𝑚 𝑥 𝑚
1
− log 𝑑𝑒𝑡 𝐼 +
𝐻 𝐾 𝐻+
𝑁𝑒 𝑒 𝑥 𝑒
The first derivative of the average secrecy
capacity with respect to SNR = P/nRNm at SNR = 0
lim
Eb
SNR
log 2
log 2
N 0 SNR 0 C S ( SNR)
C S ( 0)
The minimum bit energy in the absence of
secrecy constraints, the minimum bit energy per
secret bit is calculated. Secrecy constraints lead to
an increase if the minimum energy requirements.
We also note that the energy cost of secrecy
increases as secrecy rates increase.
We plot the secrecy rates in
bits/s/Hz/dimension as a function of the energy per
secret bit under the same assumptions and channel
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The second derivative of the average secrecy
capacity at SNR = 0 is given by
Above, we have assumed that the fading
coefficients hm and he are independent. Next, we
demonstrate that the gains are still observed even if
the channel coefficients are correlated. We again
1833 | P a g e
4. K. Rajesh et al Int. Journal of Engineering Research and Applications
ISSN : 2248-9622, Vol. 3, Issue 6, Nov-Dec 2013, pp.1831-1836
assume that hm and he are zero-mean, circularly
symmetric Gaussian random variables with
E{|hm|2} = E{|he|2} = 1. Let us denote zm = |hm|2 and
ze = |he|2. Using the bivariate Rayleigh probability
density function given in, we can easily obtain the
bivariate exponential density as
The minimum energy per secret bit is
plotted as a function of the correlation coefficient
ρ. When ρ = 0 and hence the channel coefficients
are independent, we
𝐸𝑏
log 2
=
= 1.419𝑑𝐵
𝑁0 𝑠,𝑚𝑖𝑛
𝑁𝑒
𝑁 𝑚 + 𝑁𝑒
As the correlation increases, the minimum
bit energy value increases. However, note that the
bit energy values are finite unless there is full
correlation. Note further that if there were no
fading, we would have
𝐸𝑏
log 2
=
= 𝑖𝑛𝑓
𝑁0 𝑠,𝑚𝑖𝑛
𝑁 +
1− 𝑚
𝑁𝑒
The minimum energy per secret bit, which
is attained as SNR vanishes, are discussed. In
general, fading is beneficial in terms of energy
efficiency at nonzero SNR levels as well. This is
demonstrated. In this figure, we plot the secrecy
capacity when nT = 1, nR = 5, and nE = 3. We
consider two scenarios: no fading and i.i.d.
Rayleigh fading. In the case in which there is no
fading, we assume that the channel coefficients are
all equal to 1. In the fading scenario, we assume
that the channel vectors hm and he consist of
independent and identically distributed, zero-mean
Gaussian components each with unit variance, i.e.,
E{|hm,i|2} = 1 and E{|he,i|2} = 1 for all i. We
additionally assume that hm and he are independent
of each other. Note that under these assumptions,
||hm||2 and ||he||2 are independent chi-square random
variables with 2nR and 2nE degrees of freedom,
respectively. In Fig. 4, we observe that better
performance is achieved in the presence of fading.
Indeed, energy gains tend to increase at higher
values of secrecy capacity. For instance, when Cs =
0.14 bits/s/Hz/dimension, we have a gain of
approximately 8 dB in Eb/N0 s . Note that this is a
substantial improvement in energy efficiency
www.ijera.com
We consider a general multiple-input and
multiple-output (MIMO) channel model and
identify the optimal transmission strategies in the
low-SNR regime under secrecy constraints. Since
secrecy capacity is in general smaller than the
capacity attained in the absence of confidentiality
concerns. Energy per bit requirements increase due
to security constraints.
This work, quantify these increased
energy costs and address the tradeoff between
secrecy and energy efficiency. The fundamental
benchmarks with which the performance of
practical systems can be compared, and to obtain
design guidelines for energy-efficient and secure
communication.
Observation 1: When nT=3,nR=3,nE=3; Here
the Fig.3. shows that secrecy rates comparison with
reference to signal to noise ratio.
Fig.3: Secrecy rates in nats/s/Hz/dimension vs.
SNR.
Observation 2: Where power allocation at low
SNR condition; Here the Fig.4. shows secrecy
rates comparison with reference to energy per
secret bit and also power allocation scheme in a
network.
4.1 SIMULATION RESULTS
The two critical issues of security and
energy-efficiency jointly, we study the secrecy
capacity in the low-SNR regime. The operation at
low SNRs, in addition to improving the energy
efficiency, is beneficial from a security perspective
as well. In the low-SNR regime, either the
transmission power is small or the bandwidth is
large. In either case, we have low probability of
intercept as it is generally difficult for an
eavesdropper to detect the signals in this regime.
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5. K. Rajesh et al Int. Journal of Engineering Research and Applications
ISSN : 2248-9622, Vol. 3, Issue 6, Nov-Dec 2013, pp.1831-1836
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Fig.6: Comparison of different fading channels
with no fading channel
Fig.4: Secrecy rates in bits/s/Hz/dimension vs.
energy per secret bit
Observation 3: Minimum energy per bit Vs
correlation coefficient; Here the Fig.5. shows that
minimum energy calculation with reference to
correlation coefficient and the energy levels
depends on correlation coefficient.
V.
CONCLUSION
In this paper, we investigated the tradeoff
between communication rate and average
probability of decoding error for a non-coherent
multiple antenna fading in a low-SNR regime. We
started with the assumption that the fading matrix
H has i.i.d.entries. In this regime, we showed that
using M transmit antennas and N receive antennas
allow us to realized a performance gain of N and
peakiness gain M. When both the average and peak
power are constrained, having large M can improve
both the channel capacity and the low-SNR
reliability function. In the low-SNR regime,
channel correlation can actually improve the
channel performance. In the extreme case where
the fading is fully correlated, in the sense that the
entries of the fading matrix H are either identical or
differ by a phase shift, we can achieve a
performance gain of M N. Thus, the advantage of
having multiple antennas is best realized when we
have fully correlated fading channels. This suggests
that the antennas should be placed close together in
the low-SNR regime.
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Fig. 5. Minimum energy per secret bit Eb/N0 min,s
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Observation 4: When nT=1,nR=5,nE=3;
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fading; Here the Fig.6. shows that comparison of
different fading channels and no fading condition
in a network.
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K.Rajesh Obtained B.Tech degree from
D.M.S.S.V.H.College
of
Engineering
at
Matchilipatnam in Andhrapradesh under Acharya
Nagarjuna University Guntur in INDIA and
M.Tech student in AITAM College Tekkali in
Srikakulam district Under JNTU Kakinada in India.
His area of interest is Communication Systems.
Smt K.V.Lalitha Bhavani, Received
the B.Tech degree and M.Tech from
Geetham University in Visakapatnam
in India. She is an Associate
Professor in the Department of ECE,
AITAM College Tekkali in India. Areas of interest
are Communication systems signal and image
processing.
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Optimization.
Cambridge
University
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www.ijera.com
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