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.
Implementation of Direct Sequence Spread Spectrum Communication System Using ...IJAEMSJORNAL
This paper presents the designed and implementation of spread spectrum technology for data transfer to overcome the interference problems associated with narrow band, very high frequency and ultra high frequency data transfer systems. The spread spectrum communication is used to reduce jamming of communication and provides a heightened secure communication. In this paper, the design and analyzes are implemented by Field Programmable Gate Array (FPGA) for baseband spread spectrum communication system using Pseudo Noise Sequences (PNS) for spreading digital data. The sequence generator and direct sequence spread spectrum (DSSS) for a single user is implemented in a FPGA module. The generated pseudo noise sequences are investigated for autocorrelation, cross correlation and balance properties. The bit error rates performance of the system is evaluated in multiuser environment under AWGN and reveals that, the DSSS system using pseudo noise sequences as spreading sequences significantly outperforms for the conventional PN sequences system
A cognitive radio and dynamic spectrum access – a studyijngnjournal
A basic problem facing the future in wireless systems is where to find suitable spectrum bands to fulfill the
demand of future services. While all of the radio spectrum is allocated to different services, applications
and users, observation show that usage of the spectrum is actually quite low. To overcome this problem
and improve the spectrum utilization, cognitive radio concept has been evolved. Wireless communication,
in which a transmitter and receiver can detect intelligently communication channels that are in use and
those which are not in use are known as Cognitive Radio, and it can move to unused channels. This makes
possible the use of available radio frequency spectrum while minimizing interference with other users. CRs
must have the capability to learn and adapt their wireless transmission according to the surrounding radio
environment. The application of Artificial Intelligence approaches in the Cognitive Radio is very promising
since they have a great importance for the implementation of Cognitive Radio networks architecture.
Dynamic spectrum access is a promising approach to make less severe the spectrum scarcity that wireless
communications face now. It aims at reusing sparsely occupied frequency bands and does not interfere to
the actual licensees. This paper is a review and comparison of different DSA models and methods.
Implementation of Direct Sequence Spread Spectrum Communication System Using ...IJAEMSJORNAL
This paper presents the designed and implementation of spread spectrum technology for data transfer to overcome the interference problems associated with narrow band, very high frequency and ultra high frequency data transfer systems. The spread spectrum communication is used to reduce jamming of communication and provides a heightened secure communication. In this paper, the design and analyzes are implemented by Field Programmable Gate Array (FPGA) for baseband spread spectrum communication system using Pseudo Noise Sequences (PNS) for spreading digital data. The sequence generator and direct sequence spread spectrum (DSSS) for a single user is implemented in a FPGA module. The generated pseudo noise sequences are investigated for autocorrelation, cross correlation and balance properties. The bit error rates performance of the system is evaluated in multiuser environment under AWGN and reveals that, the DSSS system using pseudo noise sequences as spreading sequences significantly outperforms for the conventional PN sequences system
A cognitive radio and dynamic spectrum access – a studyijngnjournal
A basic problem facing the future in wireless systems is where to find suitable spectrum bands to fulfill the
demand of future services. While all of the radio spectrum is allocated to different services, applications
and users, observation show that usage of the spectrum is actually quite low. To overcome this problem
and improve the spectrum utilization, cognitive radio concept has been evolved. Wireless communication,
in which a transmitter and receiver can detect intelligently communication channels that are in use and
those which are not in use are known as Cognitive Radio, and it can move to unused channels. This makes
possible the use of available radio frequency spectrum while minimizing interference with other users. CRs
must have the capability to learn and adapt their wireless transmission according to the surrounding radio
environment. The application of Artificial Intelligence approaches in the Cognitive Radio is very promising
since they have a great importance for the implementation of Cognitive Radio networks architecture.
Dynamic spectrum access is a promising approach to make less severe the spectrum scarcity that wireless
communications face now. It aims at reusing sparsely occupied frequency bands and does not interfere to
the actual licensees. This paper is a review and comparison of different DSA models and methods.
CR : smart radio that has the ability to sense the external environment, learn from the history and make intelligent decisions to adjust its transmission parameters according
to the current state of the environment.
Cognitive Radio (CR) is an adaptive, intelligent radio and network technology that can automatically detect available channels in a wireless spectrum and change transmission parameters enabling more communications to run concurrently and also improve radio operating behavior.
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
K Coverage Probability of 5G Wireless Cognitive Radio Network under Shadow Fa...ijeei-iaes
Land mobile communication is burdened with typical propagation constraints due to the channel characteristics in radio systems.Also,the propagation characteristics vary form place to place and also as the mobile unit moves,from time to time.Hence,the tramsmission path between transmitter and receiver varies from simple direct LOS to the one which is severely obstructed by buildings,foliage and terrain.Multipath propagation and shadow fading effects affect the signal strength of an arbitrary Transmitter-Receiver due to the rapid fluctuations in the phase and amplitude of signal which also determines the average power over an area of tens or hundreds of meters.Shadowing introduces additional fluctuations,so the received local mean power varies around the area –mean.The present section deals with the performance analysis of fifth generation wireless cognitive radio network on the basis of signal and interference level based k coverage probability under the shadow fading effects.
Dynamic Spectrum Allocation in Wireless sensor NetworksIJMER
Radio frequency spectrum is considered the most expensive and scarce resource among all wireless
network resources, and it is closely followed by the energy consumption, especially in low energy, battery powered
wireless sensor network devices. These days, there is a tremendous growth in the applications of wireless sensor
networks (WSNs) operating in unlicensed spectrum bands (ISM). Moreover, due to the rapid growth of wireless
devices that are designed to be operated in unlicensed spectrum bands, these spectrum bands have been overcrowded.
The problem with overcrowded spectrum or scarcity of spectrum can be solved by Dynamic Allocation of Spectrum.
In this paper we have presented the implementation and analysis of dynamic spectrum allocation in Wireless Sensors
Networks using the concept of Cognitive Radio Ad Hoc Network.
An overview of cognitive radio, comparison of cognitive radio vs. conventional radio, real-world applications for cognitive radio networks, how cognitive radios improve spectrum efficiency and address the wireless spectrum shortage.
Spectrum Sensing in Cognitive Radio Networks : QoS Considerations csandit
The rapidly growing number of wireless communication devices has led to massive increases in
radio traffic density, resulting in a noticeable shortage of available spectrum. To address this
shortage, the Cognitive Radio (CR) technology offers promising solutions that aim to improve
the spectrum utilization. The operation of CR relies on detecting the so-called spectrum holes,
the frequency bands that remain unoccupied by their licensed operators. The unlicensed users
are then allowed to communicate using these spectrum holes. As such, the performance of CR is
highly dependent on the employed spectrum sensing methods. Several sensing methods are
already available. However, no individual method can accommodate all potential CR operation
scenarios. Hence, it is fair to ascertain that the performance of a CR device can be improved if
it is capable of supporting several sensing methods. It should obviously also be able to select the
most suitable method. In this paper, several spectrum sensing methods are compared and
analyzed, aiming to identify their advantages and shortcomings in different CR operating
conditions. Furthermore, it identifies the features that need to be considered while selecting a
suitable sensing method from the catalog of available methods.
Performance Analysis of Ultra Wideband Communication SystemEditor IJMTER
Ultra-Wideband (UWB) is a radio transmission scheme that uses extremely low power
pulses of radio energy spread across a wide spectrum of frequencies. UWB has several advantages
over conventional continuous wave radio communications including potential support for high data
rates, robustness to multipath interference and fading. The paper covers Ultra Wide-Band
technology. General description, Challenges, various modulation schemes such as OOK, PAM,
PPM, and BPSK under specified Ultra Wide Band regimes: low Power spectral density, large
spreading ratio and a highly dispersive channel. The capacity and BER performance of a single user
ultra wideband communication is investigated for various modulation schemes and coded, uncoded
methods also simulated. Fading channel like Ricean and Rayleigh are compared. Channelized digital
receiver concept is discussed.
Impact of Next Generation Cognitive Radio Network on the Wireless Green Eco s...ijeei-iaes
Land mobile communication is burdened with typical propagation constraints due to the channel characteristics in radio systems.Also,the propagation characteristics vary form place to place and also as the mobile unit moves,from time to time.Hence,the tramsmission path between transmitter and receiver varies from simple direct LOS to the one which is severely obstructed by buildings, foliage and terrain. Multipath propagation and shadow fading effects affect the signal strength of an arbitrary Transmitter-Receiver due to the rapid fluctuations in the phase and amplitude of signal which also determines the average power over an area of tens or hundreds of meters. Shadowing introduces additional fluctuations, so the received local mean power varies around the area –mean. The present paper deals with the performance analysis of impact of next generation wireless cognitive radio network on wireless green eco system through signal and interference level based k coverage probability under the shadow fading effects.
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.
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.
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.
CR : smart radio that has the ability to sense the external environment, learn from the history and make intelligent decisions to adjust its transmission parameters according
to the current state of the environment.
Cognitive Radio (CR) is an adaptive, intelligent radio and network technology that can automatically detect available channels in a wireless spectrum and change transmission parameters enabling more communications to run concurrently and also improve radio operating behavior.
Welcome to International Journal of Engineering Research and Development (IJERD)IJERD Editor
journal publishing, how to publish research paper, Call For research paper, international journal, publishing a paper, IJERD, journal of science and technology, how to get a research paper published, publishing a paper, publishing of journal, publishing of research paper, reserach and review articles, IJERD Journal, How to publish your research paper, publish research paper, open access engineering journal, Engineering journal, Mathemetics journal, Physics journal, Chemistry journal, Computer Engineering, Computer Science journal, how to submit your paper, peer reviw journal, indexed journal, reserach and review articles, engineering journal, www.ijerd.com, research journals,
yahoo journals, bing journals, International Journal of Engineering Research and Development, google journals, hard copy of journal
K Coverage Probability of 5G Wireless Cognitive Radio Network under Shadow Fa...ijeei-iaes
Land mobile communication is burdened with typical propagation constraints due to the channel characteristics in radio systems.Also,the propagation characteristics vary form place to place and also as the mobile unit moves,from time to time.Hence,the tramsmission path between transmitter and receiver varies from simple direct LOS to the one which is severely obstructed by buildings,foliage and terrain.Multipath propagation and shadow fading effects affect the signal strength of an arbitrary Transmitter-Receiver due to the rapid fluctuations in the phase and amplitude of signal which also determines the average power over an area of tens or hundreds of meters.Shadowing introduces additional fluctuations,so the received local mean power varies around the area –mean.The present section deals with the performance analysis of fifth generation wireless cognitive radio network on the basis of signal and interference level based k coverage probability under the shadow fading effects.
Dynamic Spectrum Allocation in Wireless sensor NetworksIJMER
Radio frequency spectrum is considered the most expensive and scarce resource among all wireless
network resources, and it is closely followed by the energy consumption, especially in low energy, battery powered
wireless sensor network devices. These days, there is a tremendous growth in the applications of wireless sensor
networks (WSNs) operating in unlicensed spectrum bands (ISM). Moreover, due to the rapid growth of wireless
devices that are designed to be operated in unlicensed spectrum bands, these spectrum bands have been overcrowded.
The problem with overcrowded spectrum or scarcity of spectrum can be solved by Dynamic Allocation of Spectrum.
In this paper we have presented the implementation and analysis of dynamic spectrum allocation in Wireless Sensors
Networks using the concept of Cognitive Radio Ad Hoc Network.
An overview of cognitive radio, comparison of cognitive radio vs. conventional radio, real-world applications for cognitive radio networks, how cognitive radios improve spectrum efficiency and address the wireless spectrum shortage.
Spectrum Sensing in Cognitive Radio Networks : QoS Considerations csandit
The rapidly growing number of wireless communication devices has led to massive increases in
radio traffic density, resulting in a noticeable shortage of available spectrum. To address this
shortage, the Cognitive Radio (CR) technology offers promising solutions that aim to improve
the spectrum utilization. The operation of CR relies on detecting the so-called spectrum holes,
the frequency bands that remain unoccupied by their licensed operators. The unlicensed users
are then allowed to communicate using these spectrum holes. As such, the performance of CR is
highly dependent on the employed spectrum sensing methods. Several sensing methods are
already available. However, no individual method can accommodate all potential CR operation
scenarios. Hence, it is fair to ascertain that the performance of a CR device can be improved if
it is capable of supporting several sensing methods. It should obviously also be able to select the
most suitable method. In this paper, several spectrum sensing methods are compared and
analyzed, aiming to identify their advantages and shortcomings in different CR operating
conditions. Furthermore, it identifies the features that need to be considered while selecting a
suitable sensing method from the catalog of available methods.
Performance Analysis of Ultra Wideband Communication SystemEditor IJMTER
Ultra-Wideband (UWB) is a radio transmission scheme that uses extremely low power
pulses of radio energy spread across a wide spectrum of frequencies. UWB has several advantages
over conventional continuous wave radio communications including potential support for high data
rates, robustness to multipath interference and fading. The paper covers Ultra Wide-Band
technology. General description, Challenges, various modulation schemes such as OOK, PAM,
PPM, and BPSK under specified Ultra Wide Band regimes: low Power spectral density, large
spreading ratio and a highly dispersive channel. The capacity and BER performance of a single user
ultra wideband communication is investigated for various modulation schemes and coded, uncoded
methods also simulated. Fading channel like Ricean and Rayleigh are compared. Channelized digital
receiver concept is discussed.
Impact of Next Generation Cognitive Radio Network on the Wireless Green Eco s...ijeei-iaes
Land mobile communication is burdened with typical propagation constraints due to the channel characteristics in radio systems.Also,the propagation characteristics vary form place to place and also as the mobile unit moves,from time to time.Hence,the tramsmission path between transmitter and receiver varies from simple direct LOS to the one which is severely obstructed by buildings, foliage and terrain. Multipath propagation and shadow fading effects affect the signal strength of an arbitrary Transmitter-Receiver due to the rapid fluctuations in the phase and amplitude of signal which also determines the average power over an area of tens or hundreds of meters. Shadowing introduces additional fluctuations, so the received local mean power varies around the area –mean. The present paper deals with the performance analysis of impact of next generation wireless cognitive radio network on wireless green eco system through signal and interference level based k coverage probability under the shadow fading effects.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
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.
Analysis of Simulation Parameters of Pulse Shaping FIR Filter for WCDMAijsrd.com
The application of signal processing techniques to wireless communications is an emerging area that has recently achieved dramatic improvement in results and holds the potential for even greater results in the future as an increasing number of researchers from the signal process and communications areas participate in this expanding field. From an industrial viewpoint also, the advanced signal processing technology cannot only dramatically increase the wireless system capacity but can also improve the communication quality including the reduction of all types of interference. The present paper deals with simulation model of square root raised cosine pulse shaping filter for WCDMA with different parameters of the filter at 5Mhz.The present paper deals with study of Simulation Parameters (Number of Bits, Number of Errors) of Pulse Shaping FIR Filter at different value of group delay(2,4,6,8) to the calculate BER for WCDMA.
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.
SCALABILITY CONCERNS OF CHIRP SPREAD SPECTRUM FOR LPWAN APPLICATIONSijasuc
Divergent modulation schemes have been proposed for the Internet of Things (IoT). Low Power Wide Area
Networks (LPWAN) technologies are gaining unprecedented acceptance in IoT application of sensor
networks. Chirp Spread Spectrum (CSS) is a prominent modulation technique proposed for LPWAN. Chirps
can traverse long distance and are resilient to noise and Doppler effects. Noise resilience along with
transmission range and low power requirement makes CSS a preferred modulation scheme for sensor
networks. LoRaWANTM, with its physical (PHY) layer using CSS, has emerged as the widely accepted
LPWAN solution. By using CSS modulation with orthogonal spreading factors (SF), LoRa offers wide
coverage to LPWAN applications while supporting a high volume of devices. However, scalability
performance of CSS has not been inadequately modeled. As with the suitability of the modulation scheme,
there are concerns on how chirps interact with the surrounding as the number of deployments bursts out
into higher volumes. We evaluate CSS at ISM band 868 MHz for spreading factor 7 to 12 at bandwidth 125
kHz for performance and scalability. Simultaneous transmissions were simulated with repeated iterations
and conclusions are arrived on collisions rate, packet error rate, and bit error. Suitability of using CSS for
sensor networks for future deployments is commended.
SCALABILITY CONCERNS OF CHIRP SPREAD SPECTRUM FOR LPWAN APPLICATIONSijasuc
Divergent modulation schemes have been proposed for the Internet of Things (IoT). Low Power Wide Area
Networks (LPWAN) technologies are gaining unprecedented acceptance in IoT application of sensor
networks. Chirp Spread Spectrum (CSS) is a prominent modulation technique proposed for LPWAN. Chirps
can traverse long distance and are resilient to noise and Doppler effects. Noise resilience along with
transmission range and low power requirement makes CSS a preferred modulation scheme for sensor
networks. LoRaWANTM, with its physical (PHY) layer using CSS, has emerged as the widely accepted
LPWAN solution. By using CSS modulation with orthogonal spreading factors (SF), LoRa offers wide
coverage to LPWAN applications while supporting a high volume of devices. However, scalability
performance of CSS has not been inadequately modeled. As with the suitability of the modulation scheme,
there are concerns on how chirps interact with the surrounding as the number of deployments bursts out
into higher volumes. We evaluate CSS at ISM band 868 MHz for spreading factor 7 to 12 at bandwidth 125
kHz for performance and scalability. Simultaneous transmissions were simulated with repeated iterations
and conclusions are arrived on collisions rate, packet error rate, and bit error. Suitability of using CSS for
sensor networks for future deployments is commended.
SCALABILITY CONCERNS OF CHIRP SPREAD SPECTRUM FOR LPWAN APPLICATIONSijasuc
Divergent modulation schemes have been proposed for the Internet of Things (IoT). Low Power Wide Area
Networks (LPWAN) technologies are gaining unprecedented acceptance in IoT application of sensor
networks. Chirp Spread Spectrum (CSS) is a prominent modulation technique proposed for LPWAN. Chirps
can traverse long distance and are resilient to noise and Doppler effects. Noise resilience along with
transmission range and low power requirement makes CSS a preferred modulation scheme for sensor
networks. LoRaWANTM, with its physical (PHY) layer using CSS, has emerged as the widely accepted
LPWAN solution. By using CSS modulation with orthogonal spreading factors (SF), LoRa offers wide
coverage to LPWAN applications while supporting a high volume of devices. However, scalability
performance of CSS has not been inadequately modeled. As with the suitability of the modulation scheme,
there are concerns on how chirps interact with the surrounding as the number of deployments bursts out
into higher volumes. We evaluate CSS at ISM band 868 MHz for spreading factor 7 to 12 at bandwidth 125
kHz for performance and scalability. Simultaneous transmissions were simulated with repeated iterations
and conclusions are arrived on collisions rate, packet error rate, and bit error. Suitability of using CSS for
sensor networks for future deployments is commended.
SCALABILITY CONCERNS OF CHIRP SPREAD SPECTRUM FOR LPWAN APPLICATIONSijasuc
Divergent modulation schemes have been proposed for the Internet of Things (IoT). Low Power Wide Area
Networks (LPWAN) technologies are gaining unprecedented acceptance in IoT application of sensor
networks. Chirp Spread Spectrum (CSS) is a prominent modulation technique proposed for LPWAN. Chirps
can traverse long distance and are resilient to noise and Doppler effects. Noise resilience along with
transmission range and low power requirement makes CSS a preferred modulation scheme for sensor
networks. LoRaWANTM, with its physical (PHY) layer using CSS, has emerged as the widely accepted
LPWAN solution. By using CSS modulation with orthogonal spreading factors (SF), LoRa offers wide
coverage to LPWAN applications while supporting a high volume of devices. However, scalability
performance of CSS has not been inadequately modeled. As with the suitability of the modulation scheme,
there are concerns on how chirps interact with the surrounding as the number of deployments bursts out
into higher volumes. We evaluate CSS at ISM band 868 MHz for spreading factor 7 to 12 at bandwidth 125
kHz for performance and scalability. Simultaneous transmissions were simulated with repeated iterations
and conclusions are arrived on collisions rate, packet er
CDMA Transmitter and Receiver Implementation Using FPGAIOSR Journals
Abstract: Code Division Multiple Access (CDMA) is a spread spectrum technique that uses neither frequency channels nor time slots. With CDMA, the narrow band message (typically digitized voice data) is multiplied by a large bandwidth signal that is a pseudo random noise code (PN code). All users in a CDMA system use the same frequency band and transmit simultaneously. The transmitted signal is recovered by correlating the received signal with the PN code used by the transmitter. The DS - CDMA is expected to be the major medium access technology in the future mobile systems owing to its potential capacity enhancement and the robustness against noise. The CDMA is uniquely featured by its spectrum-spreading randomization process employing a pseudo-noise (PN) sequence, thus is often called the spread spectrum multiple access (SSMA). As different CDMA users take different PN sequences, each CDMA receiver can discriminate and detect its own signal, by regarding the signals transmitted by other users as noise- like interferences. In this project direct sequence principle based CDMA transmitter and receiver is implemented in VHDL for FPGA. Modelsim 6.2(MXE) tool will be used for functional and logic verification at each block. The Xilinx synthesis technology (XST) of Xilinx ISE 9.2i tool will be used for synthesis of transmitter and receiver on FPGA Spartan 3E. Keywords: CDMA, DSSS, BPSK, GOLD code.
Spread Spectrum TechniquesDescribe in detail a simple data communi.pdfakritigallery
Spread Spectrum Techniques
Describe in detail a simple data communication system that will monitor the temperature of a
remote inaccessible location and display temperature on a personal computer.
Suggest a future application for spread spectrum techniques and explain why SS would be
appropriate for that application.
Solution
Spread spectrum communication systems are widely used today in a variety of applications for
different purposes such as access of same radio interrupted or blocked by spurious transmission
from enemy), interference rejection, spectrum by multiple users (multiple access), anti-jamming
capability (so that signal transmission can not be secure communications, multi-path protection,
etc. However, irrespective of the application, all spread spectrum communication systems satisfy
the following criteria-
a) As the name suggests, bandwidth of the transmitted signal is much greater than that of the
message that modulates a carrier.
b)The power spectral density of the modulated signal is very low and usually comparable to
background noise and interference at the receiver.
DATA COMMUNICATION:
It defines as data exchange between source and receiver.
Wireless Sensor Network (WSN) typically consists of small spatially distributed devices to
cooperatively monitor physical or environmental conditions, such as temperature, sound,
vibration and etc. With WSN connectivity, data from remote sensors of different types are
collected by central unit for further processing and analysis.
WSNs are less expensive and more flexible than wired monitoring systems. There are
applications that become feasible only with WSNs because using wires between devices are too
expensive or impossible at all. For instance, in many industrial, agricultural, military or
ecological problems physical wiring is impossible or would create extreme disturbance for other
operations. WSN, compared to other existing wireless technologies, is the only technology that
targets simple communication with low data rates and low power consumption.
Each WSN node is typically equipped with:
Coding Techniques
In order to transmit anything, codes used for data transmission have to be considered. However,
this section will not discuss the coding of information (like error correction coding) but those
that act as noise-like carriers for the information being transferred. These codes are of much
greater length than those for the usual areas of data transfer, since it is intended for bandwidth
spreading.
Codes in a spread-spectrum system are used for:
Maximal sequencing is one of the more popular coding methods in a spread-spectrum system.
Maximal codes can be generated by a given shift register or a delay element of given length. In
binary shift register sequence generators, the maximum length sequence is (2^n-1) chips, where
n is the number of stages in the shift register.
A shift register generator consists of a shift register in conjunction with the appropriate logic,
which feeds back.
The peer-reviewed International Journal of Engineering Inventions (IJEI) is started with a mission to encourage contribution to research in Science and Technology. Encourage and motivate researchers in challenging areas of Sciences and Technology.
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
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These slides cover a topic on Spread spectrum in Data Communication. All the slides are explained in a very simple manner. It is useful for engineering students & also for the candidates who want to master data communication & computer networking.
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De-mystifying Zero to One: Design Informed Techniques for Greenfield Innovati...
Bi36358362
1. Pavan M. Ingale et al Int. Journal of Engineering Research and Application
ISSN : 2248-9622, Vol. 3, Issue 6, Nov-Dec 2013, pp.358-362
RESEARCH ARTICLE
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OPEN ACCESS
Various Correlation Properties of Orthogonal Spreading Codes
for CDMA Technique
Pavan M. Ingale*, Md. Manan Mujahid **, Syed Anwar Ahmed***
*(M.TECH Scholar, Department of ECE, SES’ SCET, Hyderabad, India)
**(Asst. Prof. & H.O.D, Department of ECE, SES’ SCET, Hyderabad, India)
***(Asst. Prof., Department of ECE, SES’ SCET, Hyderabad, India)
ABSTRACT
Spread Spectrum a means of signal modulation, in which the signal frequency is spread over a very wide
bandwidth. Spread spectrum technology, which was initially used in military applications, is another approach to
achieve multiple accesses. An important multiple-access technique in wireless networks and other common
channel communication systems is Code-Division Multiple Access (CDMA). Each user shares the entire
bandwidth with all the other users and is distinguished from the others by its signature sequence or code.
The sequences which are used in CDMA should have the following properties:
• There should be a balance in the number of ones and zeroes.
• The autocorrelation must be a sharp two-valued function
• The cross correlation must be as low as possible.
In this paper, we propose the generation of the orthogonal sets of codes which are able to retain the properties of
Complete Complementary (CC) codes. The proposed methods can be applied to any sequence with ideal twolevel cross-correlation
Keywords - Spread Spectrum, Orthogonal Sequences, Cross-correlation Function (CCF), Spreading Codes.
I.
INTRODUCTION
Over the last eight or nine years a new commercial
marketplace has been emerging, called spread
spectrum, this field covers the art of secure digital
communications that is now being exploited for
commercial and industrial purposes. In the next
several years hardly anyone will escape being
involved, in some way, with spread spectrum
communications. Applications for commercial spread
spectrum range from "wireless" LAN's (computer to
computer local area networks), to integrated bar code
scanner/palmtop computer/radio modem devices for
warehousing, to digital dispatch, to digital cellular
telephone communications, to "information society"
city/area/state or country wide networks for passing
faxes, computer data, email, or multimedia data[15].
"Spread-spectrum radio communications,
long a favourite technology of the military because it
resists jamming and is hard for an enemy to intercept,
is now on the verge of potentially explosive
commercial development. The reason: spreadspectrum signals, which are distributed over a wide
range of frequencies and then collected onto their
original frequency at the receiver, are so
inconspicuous as to be 'transparent [2].' Just as they
are unlikely to be intercepted by a military opponent,
so are they unlikely to interfere with other signals
intended for business and consumer users even ones
transmitted on the same frequencies. Such an
advantage opens up crowded frequency spectra to
vastly expanded use [4]. In this paper, we propose the
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generation of the orthogonal sets of codes which are
able to retain the properties of Complete
Complementary (CC) codes. The proposed methods
can be applied to any sequence with ideal two-level
cross-correlation. In 1st section we discuss the
background of spread spectrum. In 2nd section we
discuss the properties of spread spectrum. In 4th & 5th
section we introduced the Orthogonal Sequences &
their types. In 6th & 7th we discuss the characteristics
and advantages of spread spectrum and finally, brief
summaries are given in Section 8th to conclude the
paper.
II.
Background
Spread spectrum system spreads the
transmitted signal over a wide frequency band, much
wider, than the minimum bandwidth required to
transmit the information being sent. For example, a
base band signal with a bandwidth of only few
kilohertz is distributed by a spread spectrum system
over a bandwidth of many megahertz which is done by
modulating with the information to be sent with the
wideband encoding signal [5].
Fig.1. shows that spreading is achieved when
multiplying the signal with the spreading sequence.
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2. Pavan M. Ingale et al Int. Journal of Engineering Research and Application
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Fig.2. A Spectrum Analyzer Photo of a (DSSS).
Fig.1. Spreading waveforms.
Some of the properties of spread spectrum
systems are,
• Low density power spectra.
• Code division multiplexing which is possible for
multiple access.
• Selective addressing capability.
• Interference rejection.
The important forms of spread spectrum
modulation are frequency hopping, direct sequence,
time hopping, chirping and various hybrid
combinations of the above forms though only the first
two are the most important ones[10]. Frequency
hopping spread spectrum, which is also called
multiple frequency, code selected, frequency-shift
keying, is one in which a signal is spread by causing it
to hop rapidly from one frequency to another
according to a predetermined pseudorandom
sequence. Direct sequence spread spectrum systems,
which are the most widely used systems, are those in
which the signal is spread over a continuous range of
frequencies [9].
III.
Spread Spectrum
One way to look at spread spectrum is that it
trades a wider signal bandwidth for better signal to
noise ratio. Frequency hop and direct sequence are
well-known techniques today. Frequency hopping is
the easiest spread spectrum modulation to use. Any
radio with a digitally controlled frequency synthesizer
can, theoretically, be converted to a frequency
hopping radio. This conversion requires the addition
of a pseudo noise (PN) code generator to select the
frequencies for transmission or reception. A frequency
hopped system can use analog or digital carrier
modulation and can be designed using conventional
narrow band radio techniques [14]. De-hopping in the
receiver is done by a synchronized pseudo noise code
generator that drives the receiver's local oscillator
frequency synthesizer.
To qualify as a spread spectrum signal, two
criteria should be met:
1. The transmitted signal bandwidth is much greater
than the information bandwidth.
2. Some function other than the information being
transmitted is employed to determine the resultant
transmitted bandwidth.
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Fig.3. A Spectrum Analyzer Photo of a (FHSS).
Direct sequence systems - Direct sequence
spread spectrum systems are so called because they
employ a high speed code sequence, along with the
basic information being sent, to modulate their RF
carrier. Figure 2 illustrates the most common type of
direct sequence modulated spread spectrum signal [9,
12].
Frequency hopping systems - The wideband
frequency spectrum desired is generated in a different
manner in a frequency hopping system.
3.1 Spread Spectrum Properties
Signal occupies a bandwidth much larger than is
needed for the information signal.
Spread spectrum modulation is done using a
spreading code independent of the data in the
signal.
Despreading at the receiver is done by correlating
the received signal with a synchronized copy of
the spreading code.
There are some more interesting properties to
Spread Spectrum, some of them are:
Good Anti Jamming performance.
Low Power Spectral Density.
Interference Limited operation. In all situations,
the whole frequency spectrum is used.
Applying Spread Spectrum implies the reduction
of Multi path effects.
Random Access probabilities. Users can start
their transmission at any time.
Privacy due to the use of unknown random codes.
The applied codes are in principle unknown to
hostile users, i.e. each user has his own unique
code.
Multiple Accesses. More than one user shares the
same BW at the same time.
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3. Pavan M. Ingale et al Int. Journal of Engineering Research and Application
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IV.
Background for Orthogonal Sequences
The code-division multiple access (CDMA)
standard for U.S. digital cellular services is the IS-95
(Interim standard-95). Cellular systems based on this
standard include the personal communication service,
or PCS. In such a system, the reverse link (mobile
station to base station link) uses [5].
DSSS technique that employs nonbinary
orthogonal modulation using Walsh-Hadamard
signals. In another application, high-data-rate wireless
local-area networks subject to multipath interference
also employ DSSS technique along with nonbinary
orthogonal modulation using Walsh-Hadamard
signals.
4.1 Direct-Sequence Spread Spectrum
One type of direct-sequence spread spectrum
communication system employs a form of spread
spectrum modulation in which the narrowband
information-bearing data signal is spread over a wide
range of frequencies through direct multiplication with
a pseudo-random binary sequence, which is a
sequence of chips, or elemental pulses, valued -1 and
1 and has noise-like properties [16]. Sequences such
as the maximal-length linear feedback shift register
sequences or m-sequences as they are commonly
referred to in the literature, and the Gold sequences
are often used as the pseudo-random binary
sequences. In the system under consideration, msequences are used. Figure 4 gives an illustration of
the direct-sequence spreading.
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adder and 1 representing a connection to the mod-2
adder. For all LFSRs with n storage elements,
h0=hn=1. If hn = 0, then the left-most storage element
has no role in determining which sequence is
generated; and if h0 = 0, then there is no feedback
[13].
A convenient way to represent the n-stage LFSR is by
the polynomial,
h( x) x n h1 x n 1 h2 x n 2 ... hn 1 x 1
V.
Types of Sequences
5.1 Gold Sequences:
The cross correlation properties are as
important
in
communication
systems
as
autocorrelation properties. Cross correlation is a
measure of agreement between the two different
codes. The periodic cross correlation between any pair
of m-sequences is very high. Such high values of cross
correlation
are
undesirable
in
CDMA
communications. Gold developed new sequences with
better cross correlation properties called Gold
sequences [16].
5.2 Kasami Sequences:
There are two classes of Kasami Sequences:
the small set and the large set. The number of
sequences for the small set is 2
n/2
n/2
, and for the large
n
set is 2
( 2 +1), where n is the number of stages
of the shift register. The procedure for generating
Kasami sequences is similar to that used for
generating Gold sequences. The maximum cross
correlation value for any pair of Kasami sequences is
2 n / 2 +1. The maximum correlation value of the large
set of Kasami sequences is same as that of the Gold
sequences [14].
Fig.4. Direct-sequence spreading
4.2 M-Sequence
An m-sequence with period N=2n-1 is
generated using a linear feedback shift register (LFSR)
with n storage elements. A general n-stage LFSR is
shown below in Figure 6.
Fig.6. General n-stage linear feedback shift register.
Where h = (h0, h1,…,hn) is called the feedback tap
coefficient vector, and each of its elements is either a
0 or 1, with 0 representing no connection to the mod-2
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5.3 Pseudo Noise Sequences:
Pseudo noise sequences are binary-valued,
noise like sequences. They are generated by feedback
shift registers with feedback. They are similar to a
sequence of coin tossing where +1 represents a head
and -1 represents a tail.
The following characteristics are associated with
randomness.
In every period, the number of +1’s is nearly equal
to the number of -1’s.
In every period, half the runs have length one, onefourth have length two, one eighth have length
three as long as the number of runs exceeds 1.
The autocorrelation function is two valued.
Any sequence with the above properties is called a
pseudo noise sequence.
5.4 Read Muller codes:
Reed_ Muller codes are some of the oldest
error correcting codes. Error correcting codes are very
useful in sending information over long distances or
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through channels where errors might occur in the
message. They have become more prevalent as
telecommunications have expanded and developed a
use for codes that can self-correct.
VI.
Advantages of orthogonal sequences
High spectral efficiency,
The information rate that can be transmitted over
a given bandwidth in a specific communication
system is high.
Multiple access capabilities,
A channel-access scheme is based on a
multiplexing method that allows several data
streams or signals to share the same
Communication channel or physical medium.
Multiplexing is in this context provided by the
physical layer.
Robustness in the case of frequency selective
channels,
The quality of being able to withstand stresses,
pressures, or changes in procedure or
circumstance is possible for the frequency
High flexibility,
Narrow-band interference rejection,
Simple one tap equalization, etc.
VII.
sequences, or codes, are chosen orthogonal. From the
Spread Spectrum Characteristics of CDMA we
observe that it has low power spectral density, privacy
is more, and overall good performance.
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Low power spectral density. As the signal is
spread over a large frequency-band, the Power
Spectral Density is getting very small, so other
communications systems do not suffer from this
kind of communications. However the Gaussian
Noise level is increasing.
Interference limited operation. In all situations the
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Privacy due to unknown random codes. The
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Applying spread spectrum implies the reduction
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Random access possibilities. Users can start their
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Good anti-jam performance.
VIII.
CONCLUSIONS
The characteristics of CDMA codes for next
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