Abstract: MC-CDMA (Multi Carrier Code Division Multiple Access) plays an important role in modern wireless communications. Modern communication required an efficient spectrum usage and capacity and throughput.MC-CDMA provided the solution of these problems. MIMO refers to links with multiple antennas at the transmitter and receiver side. CDMA systems combined with multiple antennas is a promising technique, beyond 3G and 4G wireless communications. MIMO provides spatial diversity, which mitigates the fading. The usage of multiple antennas can significantly improve the performance of wireless communication system. This work also derives simulation through MATLAB of average bit error rate verses bit energy to noise ratio of multicarrier code division multiple access over Rayleigh channel using QPSK and BPSK modulation additive white Gaussian noise. Keywords: AWGN,BER,MC-CDMA, QPSK Modulation, Rayleigh Channel.
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.
Outage and throughput performance of cognitive radio based power domain based...TELKOMNIKA JOURNAL
This paper considers power domain based multiple access (PDMA) in cognitive radio network to serve numerous users who intend to multiple access to core network. In particular, we investigate the effect of signal combination scheme equipped at PDMA end-users as existence of direct link and relay link. This system model using relay scheme provides performance improvement on the outage probability of two PDMA end-users. We first propose a simple scheme of fixed power allocation to PDMA users who exhibit performance gap and fairness. Inspired by PDMA strategy, we then find signal to noise ratio (SNR) to detect separated signal for each user. In addition, the exact expressions of outage probability are derived in assumption that receiver can cancel out the interference completely with successive interference cancellation (SIC). By exploiting theoretical and simulation results, both considered combination schemes (Maximal Ratio Combining (MRC) and Selection Combining (SC) can achieve improved performance of two PDMA users significantly.
Dynamic Power Allocation for Mc-Cdma System Using Iterative Water Filling Alg...inventionjournals
ABSTRACT : Power control in Multi Carrier Code Division Multiple Access ( MCCDMA) based wireless cellular network is of great importance. The power allocation methodology to enhance the performance of the MCCDMA system by limiting interference noise is at the expense of signaling overhead due to sharing of Channel State Information (CSI). The distributed algorithms that manage the power level based on the user’s SINR requirements needs the complete knowledge of Channel State Information (CSI) .Since the CSI is subjected to the errors because of the imperfect channel estimation/measurement due to the time varying nature of the channels, the distributed power control algorithm is not globally optimum. The water filling algorithm is used to allocate proper power for every sub channel in order to improve channel capacity. The water filling algorithm distributes power among all users with the help of SINR that is received by the transmitter instead of getting full Channel State Information (CSI).
Effect of Interleaved FEC Code on Wavelet Based MC-CDMA System with Alamouti ...IJCSEIT Journal
In this paper, the impact of Forward Error Correction (FEC) code namely Trellis code with interleaver on
the performance of wavelet based MC-CDMA wireless communication system with the implementation of
Alamouti antenna diversity scheme has been investigated in terms of Bit Error Rate (BER) as a function of
Signal-to-Noise Ratio (SNR) per bit. Simulation of the system under proposed study has been done in M-ary
modulation schemes (MPSK, MQAM and DPSK) over AWGN and Rayleigh fading channel incorporating
Walsh Hadamard code as orthogonal spreading code to discriminate the message signal for individual
user. It is observed via computer simulation that the performance of the interleaved coded based proposed
system outperforms than that of the uncoded system in all modulation schemes over Rayleigh fading
channel.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
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.
Outage and throughput performance of cognitive radio based power domain based...TELKOMNIKA JOURNAL
This paper considers power domain based multiple access (PDMA) in cognitive radio network to serve numerous users who intend to multiple access to core network. In particular, we investigate the effect of signal combination scheme equipped at PDMA end-users as existence of direct link and relay link. This system model using relay scheme provides performance improvement on the outage probability of two PDMA end-users. We first propose a simple scheme of fixed power allocation to PDMA users who exhibit performance gap and fairness. Inspired by PDMA strategy, we then find signal to noise ratio (SNR) to detect separated signal for each user. In addition, the exact expressions of outage probability are derived in assumption that receiver can cancel out the interference completely with successive interference cancellation (SIC). By exploiting theoretical and simulation results, both considered combination schemes (Maximal Ratio Combining (MRC) and Selection Combining (SC) can achieve improved performance of two PDMA users significantly.
Dynamic Power Allocation for Mc-Cdma System Using Iterative Water Filling Alg...inventionjournals
ABSTRACT : Power control in Multi Carrier Code Division Multiple Access ( MCCDMA) based wireless cellular network is of great importance. The power allocation methodology to enhance the performance of the MCCDMA system by limiting interference noise is at the expense of signaling overhead due to sharing of Channel State Information (CSI). The distributed algorithms that manage the power level based on the user’s SINR requirements needs the complete knowledge of Channel State Information (CSI) .Since the CSI is subjected to the errors because of the imperfect channel estimation/measurement due to the time varying nature of the channels, the distributed power control algorithm is not globally optimum. The water filling algorithm is used to allocate proper power for every sub channel in order to improve channel capacity. The water filling algorithm distributes power among all users with the help of SINR that is received by the transmitter instead of getting full Channel State Information (CSI).
Effect of Interleaved FEC Code on Wavelet Based MC-CDMA System with Alamouti ...IJCSEIT Journal
In this paper, the impact of Forward Error Correction (FEC) code namely Trellis code with interleaver on
the performance of wavelet based MC-CDMA wireless communication system with the implementation of
Alamouti antenna diversity scheme has been investigated in terms of Bit Error Rate (BER) as a function of
Signal-to-Noise Ratio (SNR) per bit. Simulation of the system under proposed study has been done in M-ary
modulation schemes (MPSK, MQAM and DPSK) over AWGN and Rayleigh fading channel incorporating
Walsh Hadamard code as orthogonal spreading code to discriminate the message signal for individual
user. It is observed via computer simulation that the performance of the interleaved coded based proposed
system outperforms than that of the uncoded system in all modulation schemes over Rayleigh fading
channel.
International Journal of Engineering and Science Invention (IJESI) is an international journal intended for professionals and researchers in all fields of computer science and electronics. IJESI publishes research articles and reviews within the whole field Engineering Science and Technology, new teaching methods, assessment, validation and the impact of new technologies and it will continue to provide information on the latest trends and developments in this ever-expanding subject. The publications of papers are selected through double peer reviewed to ensure originality, relevance, and readability. The articles published in our journal can be accessed online.
COMPARATIVE PERFORMANCE ASSESSMENT OF VBLAST ENCODED 8×8 MIMO MC-CDMA WIRELES...pijans
The bit error rate performance of a V-Blast encoded 8x8 MIMO MC-CDMA wireless communication system
for different signal detection (MMSE and ZF) and digital modulation (BPSK, QPSK, DPSK, and 4QAM)
schemes for grayscale image transmission has been investigated in this paper. The proposed wireless system
employ ½-rated Convolution and cyclic redundancy check (CRC) channel encoding over the AWGN channel
and Walsh Hadamard code as an orthogonal spread code. The present Matlab based simulation study
demonstrates that the V-Blast encoded 8×8 MIMO MC-CDMA wireless system with the employment of 1⁄2-
rated convolution and cyclic redundancy check (CRC) channel encoding strategies shows good performance
utilizing BPSK digital modulation and ZF signal detection scheme in grayscale image transmission
LTE QOS DYNAMIC RESOURCE BLOCK ALLOCATION WITH POWER SOURCE LIMITATION AND QU...IJCNCJournal
3GPP has defined the long term evolution (LTE) for 3G radio access in order to maintain the future
competitiveness for 3G technology, the system provides the capability of supporting a mixture of services
with different quality of service (QoS) requirements. This paper proposes a new cross-layer scheduling
algorithm to satisfy better QoS parameters for real time applications. The proposed algorithm takes care of
allocating resource blocks (RBs) with different modulation and coding schemes (MCS) according to target
bit error rate (BER), user equipment supportable MCS, queue stability constraints and available transmit
power constraints. The proposed algorithm has been valued, compared with an earlier allocation algorithm
in terms of service rate and packet delay and showed better performance regards the real time
applications.
A DDRESSING T HE M ULTICHANNEL S ELECTION , S CHEDULING A ND C OORDINATION...pijans
We discuss a new multichannel coordination and sche
duling challenge called the Multichannel Scheduling
Cost (MSC). It is caused by the inability of the co
ntrol channel to schedule simultaneous transmission
s
resulting in data channels lying idle and their ban
dwidth underutilized. As a result, wasted bandwidth
increases as the number of data channels increases.
To address this challenge, a cyclic scheduling
Algorithm (CSA) is proposed. It employs one dedicat
ed signaling channel and 4 data channels. It is
premised on a proactive channel reservation scheme
which reduces the idleness of channels. The scheme
ensures that data channels are reserved while they
are still busy. The data channels are reserved whil
e
their remaining transmission duration is equal to t
he virtual carrier sensing duration. This gives the
next
pair sufficient time to reserve the current data ch
annel before it becomes available, limiting the MSC
to the
first cycle. The simulation results show a performa
nce benefit of the CSA scheme in addressing the eff
ects
of the MSC
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
ABSTRACT : Performance enhancement of smart antennas versus their complexity for commercial wireless
applications. The goal of the study presented in this paper is to investigate the performance improvement
attainable using relatively simple smart antenna techniques when applied to the third-generation W-CDMA air
interface. Methods to achieve this goal include fixed multi beam architectures with different beam selection
algorithms (maximum power criterion, combined beams) or adaptive solutions driven by relatively simple direction
finding algorithms. After comparing these methods against each other for several representative scenarios, some
issues related to the sensitivity of these methods are also studied, (e.g., robustness to environment, mismatches
originating from implementation limitations, etc.). Results indicate that overall, conventional beam forming
seems to be the best choice in terms of balancing the performance and complexity requirements, in particular
when the problem with interfering high-bit-rate W-CDMA 3g users is considered.
PERFORMANCE OF MIMO MC-CDMA SYSTEM WITH CHANNEL ESTIMATION AND MMSE EQUALIZATIONTamilarasan N
The quality of a wireless link can be described by three basic parameters, namely transmission rate, transmission range
and transmission reliability. With the advent of multiple-input multiple-output (MIMO) assisted Multicarrier code
division multiple access (MC-CDMA) systems, the above-mentioned three parameters may be simultaneously
improved. The MC-CDMA combined with the MIMO technique, has become a core technology for future mobile radio
communication system. However, possible potential gain in spectral efficiency is challenged by the receiver’s ability to
accurately detect the symbol due to inter symbol interference (ISI). Multipath propagation, mobility of transmitter,
receiver and local scattering cause the signal to be spread in frequency, different arrival time and angle, which results in
ISI in the received signal. This will affect overall system performance. The use of MC-CDMA mitigates the problem of
time dispersion. However, still it is necessary to remove the amplitude and phase shift caused by channel. To solve this
problem, a multiple antenna array can be used at the receiver, not only for spectral efficiency or gain enhancement, but
also for interference suppression. This can be done by the, efficient channel estimation with strong equalization. This
paper proposes MIMO MC-CDMA system, Minimum mean square error (MMSE) equalization with pilot based
channel estimation. The simulation result shows improved Bit error rate (BER) performance when the sub carrier (SC)
and antenna configuration were increased
DESIGN OF A COMPACT CIRCULAR MICROSTRIP PATCH ANTENNA FOR WLAN APPLICATIONS pijans
This paper presents the design of a compact circular microstrip patch antenna for WLAN applications which covers the band 5.15 to 5.825 GHz. The antenna is designed using 1.4mm thick FR-4 (lossy)substrate with relative permittivity 4.4 and a microstrip line feed is used. The radius of the circular patch is chosen as 7.62mm. To reduce the size and enhance the performance of the proposed antenna, a circular slot is loaded on circular patch and a square slot is etched on the ground plane of dimension 30mm×30mm. Design of the antenna is carried out using CST Microsoft Studio Sonimulation Software. The proposed antenna resonates at 5.5 GHz with a wider bandwidth of 702 MHz and it provides low return loss of -31.58 dB, good gain of 3.23 dB and directivity of 4.28 dBi and high efficiency of around 79% against the resonance frequency. The geometry of the proposed circular antenna with reduced size and its various performance parameters such as return loss, bandwidth, VSWR, gain, directivity, efficiency and radiation pattern plots are presented and discussed.
Estimation and design of mc ds-cdma for hybrid concatenated coding in high sp...eSAT Publishing House
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
On Channel Estimation of OFDM-BPSK and -QPSK over Nakagami-m Fading ChannelsCSCJournals
This paper evaluates the performance of OFDM - BPSK & -QPSK based system with and without channel estimation over Nakagami-m fading channels. Nakagami-m variants are generated by decomposition of Nakagami random variable into orthogonal random variables with Gaussian distribution envelopes. Performance of OFDM system in Nakagami channel has been reported here. The results yield the optimum value of m based on BER and SNR. Using this optimum value of m, Channel estimation over flat fading has been reported here. It has been depicted clearly from simulated graphs that channel estimation has further reduced the BER. However, threshold value of m has played a vital role during channel estimation.
Performance evaluation of 1 tbps qpsk dwdm system over isowceSAT Journals
Abstract Optical wireless communications has been in latest trends of high speed communications. They enable the use of optical wireless channel in applications like inter satellite links and underwater communications etc. In this paper, we communicate an ultra high bit rate i.e. 1 Tbps (10 x 100 Gbps) QPSK WDM System over optical Wireless communication Link. The system is a Line of Sight optical wireless link incorporating Coherent QPSK modulation Scheme for10 channels each at 100 Gbps The performance is evaluated in terms of Q-Factor and Minimum Bit Error Rate which are noticed to be in acceptable standards. The Link is analyzed under various parameters such as Power, Distance etc and maximum achievable distance is noticed to be 50,000 km at power values ranging from 0 dBm to 40 dBm
COMPARATIVE PERFORMANCE ASSESSMENT OF VBLAST ENCODED 8×8 MIMO MC-CDMA WIRELES...pijans
The bit error rate performance of a V-Blast encoded 8x8 MIMO MC-CDMA wireless communication system
for different signal detection (MMSE and ZF) and digital modulation (BPSK, QPSK, DPSK, and 4QAM)
schemes for grayscale image transmission has been investigated in this paper. The proposed wireless system
employ ½-rated Convolution and cyclic redundancy check (CRC) channel encoding over the AWGN channel
and Walsh Hadamard code as an orthogonal spread code. The present Matlab based simulation study
demonstrates that the V-Blast encoded 8×8 MIMO MC-CDMA wireless system with the employment of 1⁄2-
rated convolution and cyclic redundancy check (CRC) channel encoding strategies shows good performance
utilizing BPSK digital modulation and ZF signal detection scheme in grayscale image transmission
LTE QOS DYNAMIC RESOURCE BLOCK ALLOCATION WITH POWER SOURCE LIMITATION AND QU...IJCNCJournal
3GPP has defined the long term evolution (LTE) for 3G radio access in order to maintain the future
competitiveness for 3G technology, the system provides the capability of supporting a mixture of services
with different quality of service (QoS) requirements. This paper proposes a new cross-layer scheduling
algorithm to satisfy better QoS parameters for real time applications. The proposed algorithm takes care of
allocating resource blocks (RBs) with different modulation and coding schemes (MCS) according to target
bit error rate (BER), user equipment supportable MCS, queue stability constraints and available transmit
power constraints. The proposed algorithm has been valued, compared with an earlier allocation algorithm
in terms of service rate and packet delay and showed better performance regards the real time
applications.
A DDRESSING T HE M ULTICHANNEL S ELECTION , S CHEDULING A ND C OORDINATION...pijans
We discuss a new multichannel coordination and sche
duling challenge called the Multichannel Scheduling
Cost (MSC). It is caused by the inability of the co
ntrol channel to schedule simultaneous transmission
s
resulting in data channels lying idle and their ban
dwidth underutilized. As a result, wasted bandwidth
increases as the number of data channels increases.
To address this challenge, a cyclic scheduling
Algorithm (CSA) is proposed. It employs one dedicat
ed signaling channel and 4 data channels. It is
premised on a proactive channel reservation scheme
which reduces the idleness of channels. The scheme
ensures that data channels are reserved while they
are still busy. The data channels are reserved whil
e
their remaining transmission duration is equal to t
he virtual carrier sensing duration. This gives the
next
pair sufficient time to reserve the current data ch
annel before it becomes available, limiting the MSC
to the
first cycle. The simulation results show a performa
nce benefit of the CSA scheme in addressing the eff
ects
of the MSC
International Journal of Computational Engineering Research(IJCER)ijceronline
International Journal of Computational Engineering Research (IJCER) is dedicated to protecting personal information and will make every reasonable effort to handle collected information appropriately. All information collected, as well as related requests, will be handled as carefully and efficiently as possible in accordance with IJCER standards for integrity and objectivity.
ABSTRACT : Performance enhancement of smart antennas versus their complexity for commercial wireless
applications. The goal of the study presented in this paper is to investigate the performance improvement
attainable using relatively simple smart antenna techniques when applied to the third-generation W-CDMA air
interface. Methods to achieve this goal include fixed multi beam architectures with different beam selection
algorithms (maximum power criterion, combined beams) or adaptive solutions driven by relatively simple direction
finding algorithms. After comparing these methods against each other for several representative scenarios, some
issues related to the sensitivity of these methods are also studied, (e.g., robustness to environment, mismatches
originating from implementation limitations, etc.). Results indicate that overall, conventional beam forming
seems to be the best choice in terms of balancing the performance and complexity requirements, in particular
when the problem with interfering high-bit-rate W-CDMA 3g users is considered.
PERFORMANCE OF MIMO MC-CDMA SYSTEM WITH CHANNEL ESTIMATION AND MMSE EQUALIZATIONTamilarasan N
The quality of a wireless link can be described by three basic parameters, namely transmission rate, transmission range
and transmission reliability. With the advent of multiple-input multiple-output (MIMO) assisted Multicarrier code
division multiple access (MC-CDMA) systems, the above-mentioned three parameters may be simultaneously
improved. The MC-CDMA combined with the MIMO technique, has become a core technology for future mobile radio
communication system. However, possible potential gain in spectral efficiency is challenged by the receiver’s ability to
accurately detect the symbol due to inter symbol interference (ISI). Multipath propagation, mobility of transmitter,
receiver and local scattering cause the signal to be spread in frequency, different arrival time and angle, which results in
ISI in the received signal. This will affect overall system performance. The use of MC-CDMA mitigates the problem of
time dispersion. However, still it is necessary to remove the amplitude and phase shift caused by channel. To solve this
problem, a multiple antenna array can be used at the receiver, not only for spectral efficiency or gain enhancement, but
also for interference suppression. This can be done by the, efficient channel estimation with strong equalization. This
paper proposes MIMO MC-CDMA system, Minimum mean square error (MMSE) equalization with pilot based
channel estimation. The simulation result shows improved Bit error rate (BER) performance when the sub carrier (SC)
and antenna configuration were increased
DESIGN OF A COMPACT CIRCULAR MICROSTRIP PATCH ANTENNA FOR WLAN APPLICATIONS pijans
This paper presents the design of a compact circular microstrip patch antenna for WLAN applications which covers the band 5.15 to 5.825 GHz. The antenna is designed using 1.4mm thick FR-4 (lossy)substrate with relative permittivity 4.4 and a microstrip line feed is used. The radius of the circular patch is chosen as 7.62mm. To reduce the size and enhance the performance of the proposed antenna, a circular slot is loaded on circular patch and a square slot is etched on the ground plane of dimension 30mm×30mm. Design of the antenna is carried out using CST Microsoft Studio Sonimulation Software. The proposed antenna resonates at 5.5 GHz with a wider bandwidth of 702 MHz and it provides low return loss of -31.58 dB, good gain of 3.23 dB and directivity of 4.28 dBi and high efficiency of around 79% against the resonance frequency. The geometry of the proposed circular antenna with reduced size and its various performance parameters such as return loss, bandwidth, VSWR, gain, directivity, efficiency and radiation pattern plots are presented and discussed.
Estimation and design of mc ds-cdma for hybrid concatenated coding in high sp...eSAT Publishing House
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
On Channel Estimation of OFDM-BPSK and -QPSK over Nakagami-m Fading ChannelsCSCJournals
This paper evaluates the performance of OFDM - BPSK & -QPSK based system with and without channel estimation over Nakagami-m fading channels. Nakagami-m variants are generated by decomposition of Nakagami random variable into orthogonal random variables with Gaussian distribution envelopes. Performance of OFDM system in Nakagami channel has been reported here. The results yield the optimum value of m based on BER and SNR. Using this optimum value of m, Channel estimation over flat fading has been reported here. It has been depicted clearly from simulated graphs that channel estimation has further reduced the BER. However, threshold value of m has played a vital role during channel estimation.
Performance evaluation of 1 tbps qpsk dwdm system over isowceSAT Journals
Abstract Optical wireless communications has been in latest trends of high speed communications. They enable the use of optical wireless channel in applications like inter satellite links and underwater communications etc. In this paper, we communicate an ultra high bit rate i.e. 1 Tbps (10 x 100 Gbps) QPSK WDM System over optical Wireless communication Link. The system is a Line of Sight optical wireless link incorporating Coherent QPSK modulation Scheme for10 channels each at 100 Gbps The performance is evaluated in terms of Q-Factor and Minimum Bit Error Rate which are noticed to be in acceptable standards. The Link is analyzed under various parameters such as Power, Distance etc and maximum achievable distance is noticed to be 50,000 km at power values ranging from 0 dBm to 40 dBm
Design And Simulation of Modulation Schemes used for FPGA Based Software Defi...Sucharita Saha
Design of a BPSK and QPSK digital Modulation scheme and its implementation on FPGAs for universal mobile telecommunications system and SDR applications. The simulation of the system is made in MATLAB Simulink environment and System Generator, a tool used for FPGA design. Hardware Co-Simulation is designed using VHDL a hardware description language targeting a Xilinx FPGA and is verified using MATLAB Simulink. It is then converted to VHDL level using Simulink HDL coder. The design is synthesized and fitted with Xilinx 14.2 ISE Edition software, and downloaded to Spartan 3E (XC3S500E) board.
This presentation covers:
Some basic definitions & concepts of digital communication
What is Phase Shift Keying(PSK) ?
Binary Phase Shift Keying – BPSK
BPSK transmitter & receiver
Advantages & Disadvantages of BPSK
Pi/4 – QPSK
Pi/4 – QPSK transmitter & receiver
Advantages of Pi/4- QPSK
Evaluation of titanium in hydrochloric acid solutions containing corrosion in...IOSR Journals
Currently, the use of titanium alloys components and coating (clad) in petroleum subsea production systems continues to increase. Titanium alloys are lightweight, very flexible; have greater mechanical resistance relationship showing excellent resistance to corrosion and fatigue in ambient seawater and marine environments. The rate of corrosion of titanium alloys are low for hydrochloric acid (3%), however, in the acidification operations from petroleum well is necessary the use of corrosion inhibitors, because the concentration of hydrochloric acid varies from 10 to 28%. A corrosion inhibitor for acidification can be defined as a substance or mixture of substances which are added to the corrosive medium aim inhibit or minimize the action of the corrosive medium. This paper presents the laboratory tests made with titanium coupons subjected to hydrochloric acid solution 10% (weight %), in temperatures of 50° C and 70° C, and additions of phenylamine (aniline), thiocarbamide and β-naphthol as corrosion inhibitors. The results showed that the corrosion protection inhibitors exerted by varies from 50 to 80% depending on the concentration of inhibitors and temperatures used in the tests.
PERFORMANCE EVALUATION OF MC-CDMA SYSTEM OVER RAYLEIGH FADING CHANNELIJCSES Journal
Multi Carrier Code Division Multiple Access (MC-CDMA) is a well known technique for high speed
wireless data transmission .Two advanced technology was included in the MC-CDMA structure, such as
orthogonal frequency division multiplex (OFDM) and the code division multiple access (CDMA),so that it
benefits from the robustness of OFDM against multipath environment and from the capability of multiuser
multiplexing services that is achieved via (CDMA) system. MC-CDMA is a multicarrier spread spectrum
system which is classified as the candidate scheme for future mobile radio systems. In this paper MCCDMA
system, with Rayleigh fading channel and 16QAM array modulation, was simulated to investigate
the effects of different parameters on the system performance, such as processing gain; number of paths;
number of users; interleaving; and coding ratio.MC-CDMA performances can be considerably improved
by proper selection of these parameters. As expected, results show that MC-CDMA has a better performance over CDMA system.
COMPARATIVE PERFORMANCE ASSESSMENT OF V- BLAST ENCODED 8×8 MIMO MC-CDMA WIREL...pijans
The bit error rate performance of a V-Blast encoded 8x8 MIMO MC-CDMA wireless communication system
for different signal detection (MMSE and ZF) and digital modulation (BPSK, QPSK, DPSK, and 4QAM)
schemes for grayscale image transmission has been investigated in this paper. The proposed wireless system
employ ½-rated Convolution and cyclic redundancy check (CRC) channel encoding over the AWGN channel
and Walsh Hadamard code as an orthogonal spread code. The present Matlab based simulation study
demonstrates that the V-Blast encoded 8×8 MIMO MC-CDMA wireless system with the employment of 1⁄2-
rated convolution and cyclic redundancy check (CRC) channel encoding strategies shows good performance
utilizing BPSK digital modulation and ZF signal detection scheme in grayscale image transmission.
Comparative Performance Assessment of V-Blast Encoded 8×8 MIMO MC-CDMA Wirele...pijans
The bit error rate performance of a V-Blast encoded 8x8 MIMO MC-CDMA wireless communication system
for different signal detection (MMSE and ZF) and digital modulation (BPSK, QPSK, DPSK, and 4QAM)
schemes for grayscale image transmission has been investigated in this paper. The proposed wireless system
employ ½-rated Convolution and cyclic redundancy check (CRC) channel encoding over the AWGN
channel and Walsh Hadamard code as an orthogonal spread code. The present Matlab based simulation study
demonstrates that the V-Blast encoded 8×8 MIMO MC-CDMA wireless system with the employment of 1⁄2-
rated convolution and cyclic redundancy check (CRC) channel encoding strategies shows good performance
utilizing BPSK digital modulation and ZF signal detection scheme in grayscale image transmission
Successful interference cancellation with Blind Equalization method for MC-CD...IJTET Journal
Abstract— The increasing demand for wireless services has created the need for cost effective transmission techniques that can exploit scarce spectral resources efficiently. Inorder to achieve the high data rates needed to meet the quality of service requirements of future multimedia applications, MC-CDMA has been considered as good air-interface candidate, especially for the downlink. However, the user capacity of MC-CDMA system is essentially limited by interference. This interference can be mitigated by employing precoding techniques, IB-DFE based receivers and other efficient interference suppression techniques. In the proposed system, combined Iterative IA precoding at the transmitter with IB-DFE based processing at the receiver is suggested for MC-CDMA systems. The matrices for this nonlinear space-frequency equalizer are obtained by minimizing the overall MSE of all data streams at each subcarrier.
Error Control and performance Analysis of MIMO-OFDM Over Fading ChannelsIOSR Journals
ABSTRACT: Multiple Input Multiple Output is a wireless technology that uses multiple transmitters and
receivers to transfer more data at the same time. Orthogonal Frequency Division Multiplexing, an FDM
modulation technique which splits the signal into multiple smaller sub-signals that are then transmitted
simultaneously at different frequencies to the receiver. OFDM technique spreads the data over number of
carriers which are at specific predefined frequencies. This reduces or eliminates the ISI. Forward error
correction or channel coding is a technique used for controlling errors in data transmission over unreliable or
noisy communication channels. The objective of our proposed paper is to implement the FEC into the MIMO
OFDM systems and its performance is analysed by using MATLAB over different fading channels. For
modulation it employs M-QAM which combines both ASK and PSK thereby enabling several bits to be
transmitted per symbol. The performance of MIMO-OFDM system is evaluated by BER Vs SNR when the bits
propagates through the different fading channels.
Keywords– OFDM, MIMO, QAM, FEC, BER.
Estimation and design of mc ds-cdma for hybrid concatenated coding in high sp...eSAT Journals
Abstract The design of Multi Carrier Direct Sequence Code Division Multiple Access (MC-DS-CDMA) structure which generalizes serial and parallel concatenated code is investigated to this project. This model is ideal for designing various codes in the performance of both error floor and water floor region. We propose a concatenated code for transmitter block which is used for multi carrier direct sequence CDMA technique. Simulation results of MC-DS-CDMA uplink system using Cadence software shows the various parameters such as memory, Execution time and number of transient steps required for the Execution of MC-DS-CDMA uplink system was estimated and also power consumed was determined for each block in the transmitter. An improved concatenated code model is used for uplink mobile communication. Further system performance improvements can be obtained by concatenating inner code and outer code and the results of computer simulations demonstrate that the performance of the concatenated code was investigated. Keywords: Code Division Multiple Access, Concatenated code, inner code, outer code, interleaving and power analysis.
Combination of iterative IA precoding and IBDFE based Equalizer for MC-CDMAEditor IJMTER
Interference alignment (IA) Precoding is a generalization of beam forming to
support multi-stream (or multi-layer) transmission in multi-antenna wireless communications.
Another FDE receivers supported the iterative block decision-feedback equalization (IBDFE), that doesn't use cryptography inside the iterative method will expeditiously exploit the
inherent space-frequency diversity of the MC-CDMA systems. In this paper we have a
tendency to discuss the combination of Pseudo-random sequence generator based iterative IA
precoding and IBDFE based Equalizer for MC-CDMA systems. The using of this sequence
generator we will be able to generate efficient pulse thus the performance might be able to
increase the performance of the system. In receiver aspect, first a linear filter is employed to
cut back the inter-user aligned interference, and so associate iterative FDE receiver is meant
to expeditiously separate the abstraction streams within the presence of residual inter-user
aligned interference at the output of the filter. The IBDFE based receiver primarily wont to
scale back the inter-user aligned interference and overall mean sq. error (MSE) at every
subcarrier in MC-CDMA and additionally scale reduce the no of iterations at the transmitter.
In this system achieves the most degrees of freedom provided by the IA precoding, and also
provide high space-diversity gain.
Peak to Average Power Ratio Reduction in Mc Cdma System by Using Pulse Shapin...IOSR Journals
Abstract: One of the drawback of multicarrier code division multiple access (MC CDMA) is the high peak to
average power ratio (PAPR). In this paper A novel scheme based on pulse shaping described for PAPR
reduction. Here three different pulse shaping filters (Raised cosine, Sinc power pulse and Nyqist pulse) are
described for PAPR reduction in MC CDMA system. The method is based on the proper selection of the pulses
for shaping the different sub carriers of the MC CDMA modulation scheme. It is shown by computer simulation
that the scheme achieves the significant improvement in PAPR reduction in MC CDMA system. Its
implementation complexity is much low in comparison to the previous published methods. Thus pulse shaping
technique can be used not only to shape the spectrum of the transmitted signal but also to reduce its PAPR. In
computer simulation It is observed that by using nyquist pulse near about 6.8 db PAPR is obtained. Which is
considerable PAPR reduction than a PAPR value of Original MC CDMA signal
Keywords: MC CDMA, PAPR, PULSE SHAPING, BPSK
IOSR Journal of Electronics and Communication Engineering(IOSR-JECE) is an open access international journal that provides rapid publication (within a month) of articles in all areas of electronics and communication engineering and its applications. The journal welcomes publications of high quality papers on theoretical developments and practical applications in electronics and communication engineering. Original research papers, state-of-the-art reviews, and high quality technical notes are invited for publications.
MIMO-OFDM (Multi Input Multi Output- Orthogonal Frequency Division Multiplexing) system is very popular technique for mobile communication. We found that Ergodic channel capacity has some limitation in MIMO-OFDM system. So Ergodic channel capacity optimization is necessary to improve the performance of MIMO-OFDM System.
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Improving quality of service using ofdm technique for 4 th generation networkeSAT Journals
Abstract The migration to 4G networks will bring a new level of expectation to wireless communications. As after digital wireless revolution made mobile phones available for everyone, the higher speeds and packet delivery of 4G networks will make high quality multimedia available everywhere. The key to achieving this higher level of service delivery is a new air interface, OFDM, which is in turn enabled by the high level of performance. OFDM provides a robust signal that requires relatively little power yet uses bandwidth very efficiently. Carriers will benefit from greater flexibility by using OFDM, since in the same spectrum they will be able to offer more channels, including higher ‘bandwidth channels, with more types of services. Currently these systems are still being defined and prototyped. Achieving higher data rates requires OFDM systems to make more efficient use of the bandwidth than CDMA systems. One method of achieving this higher efficiency is through the use of higher order modulation. In this paper we have compared two digital modulation techniques 32QAM and 64QAM used for digital transmission of data. Our main objective to develop this configuration is to compare the performance of each modulation techniques. Comparison is done by Bit Error Rate analysis of both modulation techniques. We have developed existing configurations and improved them with high quality senders and receivers using MATLAB technology. In this paper we have also considered how OFDM can improve the real time video streaming over the wireless network. We have considered the problem of multiuser video streaming over OFDM. OFDM is a multi carrier modulation. The growing interest in Multicarrier Transmission by researchers and product developers motivated us to propose this topic for a special issue of Wireless Video transmission and Communications. Index Terms: QAM’ Quadrature Amplitude Modulation, OFDM' Orthogonal Frequency Division Multiplexing, QoS’ Quality of service
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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.
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Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
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Indigenized remote control interface card suitable for MAFI system CCR equipment. Compatible for IDM8000 CCR. Backplane mounted serial and TCP/Ethernet communication module for CCR remote access. IDM 8000 CCR remote control on serial and TCP protocol.
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Performance Comparison of Multi-Carrier CDMA Using QPSK and BPSK Modulation
1. IOSR Journal of Electronics and Communication Engineering (IOSR-JECE)
e-ISSN: 2278-2834,p- ISSN: 2278-8735.Volume 7, Issue 3 (Sep. - Oct. 2013), PP 61-66
www.iosrjournals.org
www.iosrjournals.org 61 | Page
Performance Comparison of Multi-Carrier CDMA Using
QPSK and BPSK Modulation
Karmjeet Singh1
, Er. Rajbir Kaur2
1
(Student University college of Engg, Punjabi University Patiala, India )
2
(Assist. Professor University college of Engg, Punjabi University Patiala)
Abstract: MC-CDMA (Multi Carrier Code Division Multiple Access) plays an important role in modern
wireless communications. Modern communication required an efficient spectrum usage and capacity and
throughput.MC-CDMA provided the solution of these problems. MIMO refers to links with multiple antennas at
the transmitter and receiver side. CDMA systems combined with multiple antennas is a promising technique,
beyond 3G and 4G wireless communications. MIMO provides spatial diversity, which mitigates the fading. The
usage of multiple antennas can significantly improve the performance of wireless communication system. This
work also derives simulation through MATLAB of average bit error rate verses bit energy to noise ratio of
multicarrier code division multiple access over Rayleigh channel using QPSK and BPSK modulation additive
white Gaussian noise.
Keywords: AWGN,BER,MC-CDMA, QPSK Modulation, Rayleigh Channel.
I. INTRODUCTION
Wireless communications is an emerging field, which has seen enormous growth in the last several
years. The growth of video, voice and data communication over the Internet, and the equally rapid pervasion of
mobile telephony, justifies expectations for mobile multimedia. Due to this growth of multimedia
communication, the users demanded high date rate communication systems in wireless environment where the
spectral resource is scarce. To fulfill the requirements new technologies like Code Division Multiple Access
and Orthogonal Frequency Division Multiplexing (OFDM) are few promising systems for the 4G
communication standards. Unique codes are used distinguish different users using same frequency band is the
basic idea behind CDMA. This led to an achievement of soft capacity with limitation self-interference and
Multiple User Interference (MUI). Thus the channel characteristics and spreading code characteristics which are
responsible for the above interference should be taken care to increase the capacity[1].
II. MULTI-CARRIER CDMA OVERVIEW
2.1. Multi-carrier CDMA (MC-CDMA)
Two main variations of the MC spread spectrum systems are the MC-CDMA (frequency domain
spreading) and MC direct sequence CDMA (MC-DS-CDMA) (time domain spreading). One way of looking at
MC-CDMA is as a combination of CDMA and OFDM, resulting in better frequency diversity and higher data
rates. In MC-CDMA, each symbol is spread using code chips and transmitted on several subcarriers. There is no
necessity for the number of carriers to be equal to the code length; thus offering a degree of flexibility in our
design.MC-DS-CDMA differs in the fact that the data is spread in time domain rather than in frequency; with
each sub channel representing a regular DS-CDMA system. The principle of MCCDMA is that a single data
symbol is transmitted over independent subcarriers. The eminent advantage of MC-CDMA is the increase in
bandwidth efficiency; the reason being the multiple access made possible through proper systems design using
orthogonal codes [2-3].
2.2. Need for MCCDMA
MC-CDMA takes advantage of both OFDM and CDMA and makes an effective efficient transmission
system by spreading the input data symbols with spreading codes in frequency domain. It uses a number of
narrowband orthogonal subcarriers with symbol duration longer than the delay spread. This makes it unlikely
for all the subcarriers to be affected by the same deep fades of the channel at the same time thereby performance
increases. During transmission becomes easier with longer symbol durations. As the number of paths increases
the performance of the two systems improves at first due to diversity, then, it starts to deteriorate due to the
increased interference from large number of paths of all users. In general, there is an optimum number of paths
that depends on the system used and the number of users. As the number of users increases, interference from all
users through all paths increases. Therefore, the optimum number of paths decreases [4].
2. Performance Comparison of Multi-Carrier CDMA Using QPSK and BPSK Modulation
www.iosrjournals.org 62 | Page
III. Mc-Cdma Block Diagram
In this section we describe the transmitter and receiver model of MC-CDMSA system. Here symbols
are modulated on many subcarriers to introduce frequency diversity instead of using only one carrier like
CDMA. Thus MC-CDMA is robust against deep frequency selective fading compared to DS-CDMA[2].Each
user data is first spread using a given high rate spreading code in frequency domain. A fraction of the symbol
corresponding to a chip of the spreading code is transmitted through different subcarriers[5].
3.1. MCCDMA Transmitter Model
MC-CDMA transmitter is similar to OFDM transmitter with small difference. In OFDM many
different symbols are transmitted by subcarriers but in MC-CDMA same symbol is transmitted by different
subcarriers. The explanation of the above concept is clearly shown in figure1.The input data rate symbols are
converted to parallel streams. Then each parallel stream is spread using spreading codes like Walsh, Hadamard
etc.
Fig. 1. MCCDMA Transmitter
The OFDM system associated with the CDMA system converts the symbols to time domain samples
by Inverse Fast Fourier Transform (IFFT) and assigns a subcarrier for each symbol. Then the subcarriers are
multiplexed to form as a serial stream. Before the transmission the serial stream is converted to blocks and each
block is separated by a guard frame. The guard frame is usually a zero symbols or known symbols. In OFDM
the guard symbols are cyclic prefix of the block where a part of the symbols belonging to a block is appended
which has various advantages.
In this figure, the main difference between MCCDMA &OFDM is that the MC-CDMA scheme
transmits the same symbol in parallel through several subcarriers whereas the OFDM scheme transmits different
code of the user in the frequency domain. The input data stream is multiplied by the spreading code .The users
are separated by different codes. All data corresponding to the total number of sub carriers are modulated in
baseband by an inverse fast Fourier transform (IFFT) and converted back into serial data. Then, a cyclic prefix
is inserted between the symbols which is a repeat of the end of the symbols at beginning, to combat the inter-
symbol interference (ISI) and the inter-carrier interference (ICI) caused by multipath fading. And hence the
cyclic prefix length is chosen such that it is greater than the delay spread of the channel. In MC-CDMA
transmission, it is essential to have frequency non selective fading over each sub carrier. Therefore, if the
original symbol rate is high enough to become subject to frequency selective fading [6], the input data have to
be serial to parallel (SIP) converted into parallel data sequences and each SIP output is multiplied with the
spreading code of length GMC .In order to improve the performance of the system, an appropriate approach for
channel estimation is, to use dedicated pilot symbols that are periodically inserted in the transmission frame (in
the time domain) , also known as block-type pilot channel estimation. The pilot tones can also be inserted into
each symbol (in the frequency domain) with a given frequency spacing; this is known as comb-type pilot the
channel estimation[6-7].
3.2. MCCDMA Receiver model
The MCCDMA receiver configuration for the jth
user is shown in Figure 2. The received signal is first
down converted.
3. Performance Comparison of Multi-Carrier CDMA Using QPSK and BPSK Modulation
www.iosrjournals.org 63 | Page
Fig. 2. MCCDMA Receiver
Then, the cyclic prefix is removed and the remaining samples are serial to parallel converted to obtain
the m-subcarriers components (corresponding to the ajp data), where m = 1,2, ... , GMC The m-subcarriers are
first demodulated by a fast Fourier transform and then multiplied by the gain qi to combine the received signal
energy scattered in the frequency domain
IV. Mimo Overview
MIMO systems use multiple antennas at both transmitter and receiver, so both transmit and receive
diversity are applied to mitigate fading resulting from signal fluctuations through the wireless channel. Based on
the degree at which the multiple data replicas are faded independently, the system provides diversity gains
representing the difference in SNR at the output of the diversity combiner compared to that of single branch
diversity at certain probability level. A MIMO system consisting of N transmit antenna elements equal to eight,
and of M receive antenna elements equal to two was modeled, accordingly diversity order of 16 can be
achieved. Combining the multiple versions of the signals created by different diversity schemes is needed for
improving the performance. The paper applies maximal ratio combining (MRC) technique using maximum-
likelihood (ML) decoder to combine these M received signals to resonate on the most likely transmitted signal.
The sum of the received SNRs form these M different paths is the effective received SNR of the system with
diversity M. The receiver needs to demodulate all M receive signals in case of MRC for a source with M
independent signals in the receive antennas[8-9].
V. Simulation Of Mc-Cdma
Here we discuss BER for QPSK in a Rayleigh multipath channel. In discussion on Rayleigh channel, a
circularly symmetric complex Gaussian random variable is considered which is of the form, h = hre + jhim where,
real and imaginary parts are zero mean independent and identically distributed (iid) Gaussian random variables
with mean 0 and variance ợ2
.The magnitude |h| which has a probability density, p(h) = h/ợ2
e-(2h/ợ2 )
,h≥0 is called
a Rayleigh random variable. This model, called Rayleigh fading channel model, is reasonable for an
environment where there are large number of reflectors.
The received signal in Rayleigh fading channel is of the form, y = hx+ n ,where ' y' is the received
symbol, h ' is complex scaling factor corresponding to Rayleigh multipath channel, 'x' is the transmitted
symbol(taking values +1' s and -1' s)and 'n' is the Additive White Gaussian Noise (A WGN) Assumptions:
1) The channel is flat fading - means that the multipath channel has only one tap. So, the convolution operation
reduces to a simple multiplication.
2) The channel is randomly varying in time – meaning each transmitted symbol gets multiplied by a randomly
varying complex number 'h' . Since 'h' is modeling a Rayleigh channel, the real and imaginary parts are
Gaussian distributed having mean 0 and variance 1/2.
3) The noise 'n' has the Gaussian probability density function with
P(n) = (1/ √ 2 πợ2
)e-(n-µ)2/2ợ2
,µ = 0 and ợ2
=N0/2 (1) .
4) T he channel ' h ' is known at the receiver. Equalization is performed at the receiver by dividing the received
symbol y by the h. ỳ= y/h= (hx+n)/ h= x + ṅ, where, ṅ= n/h his the additive noise scaled by the channel
coefficient.
4. Performance Comparison of Multi-Carrier CDMA Using QPSK and BPSK Modulation
www.iosrjournals.org 64 | Page
5.1 Bit Error Rate
BER computation in A WGN, the probability of error for transmission of either + 1 or -1 is computed
by integrating the tail of the Gaussian probability density function for a given value of bit energy to noise ratio
Eb/ No. The bit error rate is,
Pb = 1/2 erfc(√( Eb/No )) (2)
.However in the presence of channel „ h ' , the effective bit energy to noise ratio is |h|(Eb/No). So the bit error
probability for a given value of „h' is,
Pb/h=1/2 erfc(√(|h|2
Eb/No ))=1/2erfc(√ᵞ) (3)
where ᵞ =|h|2
(Eb/No). To find the error probability over all random values of | h|2
, one must evaluate the
conditional probability density function Pb/h over the probability density function of ᵞ. [10].
5.2 Simulation model
Fig. 3. simulation model of MC-CDMA
We performs the following procedure: Initially we generate random QPSK modulated and BPSK modulation
symbols +1's and -l's, then we pass them through AWGN channel after that we demodulate the received symbol
based on the location in the constellation, then we count the number of errors finally repeat the same for
multiple Eb/No. Fig. 3 shows the simulation model of the MC-CDMA system. Fig. 4 shows the transmitted
signal. Fig. 5 shows the power level of the transmitting signal. And Fig. 6 shows the received signal.
Fig. 4 Transmitted signal
5. Performance Comparison of Multi-Carrier CDMA Using QPSK and BPSK Modulation
www.iosrjournals.org 65 | Page
Fig. 5 shows the power level of the transmitting signal
Fig. 7 shows the simulated result in term of BER using one transmitting antenna and one receiving antenna for
QPSK modulation and BPSK modulation technique. The result shows that QPSK modulation technique has
better result than QPSK modulation technique. Fig. 8 BER Using two transmitting antenna and two receiving
antenna for QPSK modulation technique. The result show that it has better result than one transmitting and
receiving antenna due antenna diversity.
Fig. 6 shows the received signal
Fig. 7 BER Using one transmitting antenna and one receiving antenna for QPSK and BPSK
Modulation technique.
6. Performance Comparison of Multi-Carrier CDMA Using QPSK and BPSK Modulation
www.iosrjournals.org 66 | Page
Fig 8 BER Using two transmitting antenna and two receiving antenna
VI. Conclusion
In this paper we have tried to study and implement the Multi- Carrier CDMA system using and derive
the BER Vs Eb/No performance for MCCDMA communication system using variable number of bits with QPSK
and BPSK modulation on Rayleigh channel and Additive White Gaussian Noise. Simulation of BER Vs Eb/No
with QPSK modulation shows that as BER performance decreases, the bit energy to noise ratio, Eb / No
increases. We noted that multiple with more numbers of antennas has better performances due to the antenna
diversity. Here in MIMO MCCDMA signals received will never be corrupted because copy of same signals are
transmitted over all subcarriers and error or overlapping of signals will never take place because of
orthogonality property
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[4] Lui, Hui (2000), “Signal processing application in CDMA communication”.
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[6] Hsieh, M.-H. and Wei, C.-H. (1998), “Channel estimation for OFDM systems based on comb-type pilot arrangement in frequency
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[9] Maleki-Tehrani, A Hassibi, Cioffi, J.M, "Adaptive Equalization of Multiple input Multiple output (MIMO) frequency selective
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[10] Pragya Pallavi, Pradipta Dutta,”Muti-Carrier CDMA Overview with BPSK Modulation In Rayleigh Channel”, IEEE, 2010.