Diversity Performance of a Wavelet-Packet-Based Multicarrier Multicode CDMA Communication System
Authors : Maryam M. Akho-Zahieh; Okechukwu C. Ugweje
Abstract : In this paper, we propose and analyze a novel multicarrier (MC) multicode (MCD) code-division multiple-access (CDMA) system employing wavelet packets (WPs) for modulation. This system can achieve robust performance against multipath fading due to the localization of WPs in the time and frequency domains. The analytical framework is presented, and the system performance with diversity is evaluated by means of bit error rates and the outage probability. Since WPs have lower sidelobes compared to sinusoidal carriers, our system is very effective in reducing the problem of intercarrier interference. The effects of system parameters (e.g., order of diversity, fading parameters, and WP type) were investigated. The major contribution is to compare the performance of the system to that of the MC/MCD-CDMA system that is based on sinusoidal carriers. The results reveal a considerable performance improvement of our proposed system over the MC/MCD-CDMA system.
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Wavelet packet-based MC/MCD-CDMA communication system
Authors : MM Akho-Zahieh, OC Ugweje
Abstract : A novel wavelet packet based multicarrier multicode coded division multiple access (CDMA) system is developed and analysed. The effect of wavelet family and the number of wavelet packets superstream are investigated in terms of signal-to-noise plus interference ratio. Performance of the system is compared to several CDMA based systems. Results show that the system performs significantly better than other systems.
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Effect of Diversity and Filtering on the Performance of Wavelet Packets Base Multicarrier Multicode CDMA System
Authors : Maryam M Akho-Zahieh, Nasser Abdellatif
Abstract : In Wavelet Packets Based Multicarrier Multicode CDMA system, the multicode (MCD) part ensures the transmission for high speed and flexible data rate, the multicarrier (MC) part ensures the flexibility of handling multiple data rates, and wavelet packets modulation technique contributes to the mitigation of the interference problems. The CDMA system can suppress a given amount of interference. In this paper, the receiver employs suppression filter (SF) to mitigate the effect of narrow-band jammer interference and diversity techniques to reduce multiple access interference. The framework for the system and the performance evaluation are presented in terms of bit error rate (BER) over a Nakagami fading channel. Also, we investigate how the performance is influenced by various parameters, such as the number of taps of the SF, the ratio of narrow-band interference bandwidth to the spread-spectrum bandwidth, the diversity order, the fading parameter and so on. Finally, the performance of the system is compared with the performance Sinusoidal (Sin) based MC/MCD CDMA system.
Keywords : Wavelet Packets, Multicarrier, Multicode, Diversity, Suppression Filter
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Performance analysis of wavelet packet multirate multicarrier multicode CDMA for wireless multimedia communications
Authors : Maryam M Akho-Zahieh, Nasser Abdellatif
Abstract : Different kinds of Multirate (MR) communication systems, such as multicode (MCD) scheme and variable spreading length (VSL) schemes, have been considered for accommodating information sources with different data rates in Multicarrier code-division multiple access (MC-CDMA). In this paper, we propose the use of MCD scheme for MR services in MC/MCD-CDMA system that employs wavelet packets (WPs) as subcarriers. The bit error rate (BER) performance for the system was investigated by means of analytical methods and numerical results in a slow fading frequency selective Nakagami channel. The performance analysis includes the effects of diversity techniques, channel intensity profile, diversity order and fading parameter. Also, the effects of different service rates and number of users in each service rate were investigated. The performance of the system was compared to that of MC/MCD-CDMA based on sinusoidal carrier. Results reveal that BER performance is proportional to the service rate and our proposed system outperform the other system.
Keywords : Multirate, Multicode, Wavelet packet, Multicarrier, CDMA
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Performance of wavelet packets based multicarrier multicode CDMA communication system in the presence of narrowband jamming
Authors : Maryam Akho-Zahieh, Khalil Saleh, Nasser Abdellatif
Abstract : In this paper, the performance of multicarrier (MC), multicode (MCD), code division multiple access (CDMA) system employing wavelet packets (WPs) for modulation in the presence of narrowband jamming is investigated. The system's performance is evaluated by means of bit error rate (BER) and outage probability (P out ). The effects of channel intensity profile, type of wavelet families and their filters length, number of superstreams of wavelets and number of substreams on the system performances were investigated by means of analytical methods and numerical results. Also, the performance of the system is compared to that of MC/MCD-CDMA based on sinusoidal carrier. Results reveal considerable performance improvement of MC/MCD-CDMA system based on WPs carrier over the system based on sinusoidal carrier.
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Effect of jamming and diversity on the performance of a wavelet packet based multicarrier multicode CDMA communication system
Authors : Maryam M Akho-Zahieh, Nasser Abdellatif
Abstract : : In this paper, the performance of multicarrier (MC), multicode (MCD), code division multiple access (CDMA) system employing wavelet packets (WPs) as subcarriers for modulation in the presence of narrowband interference is investigated. The performance analysis include the effects of diversity techniques such as selection, equal gain and maximal ratio combining. The system performance is evaluated by means of bit error rate (BER) and outage probability. The effects of system parameters such as channel intensity profile, diversity order and fading parameter on the system performances were investigated by means of analytical methods and numerical results. Also, the effect of jamming power is investigated. The performance of the system is compared to that of MC/MCD-CDMA based on sinusoidal carrier. Results reveal considerable performance improvement of the system that employ diversity techniques over the one without diversity and of our proposed system over the other system.
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Narrow-band interference suppression in wavelet packets based multicarrier multicode CDMA overlay system
Authors : Maryam M. Akho-Zahieh,Nasser Abdellatif
Abstract : The wavelet packets based multicarrier (MC) multicode (MCD) code-division multiple-access (CDMA) transceiver consists of the MCD part, which ensures the transmission for high speed and flexible data rate; the MC part contributing to robustness to frequency-selective fading and flexibility for handling multiple data rates; and wavelet packets (WPs) modulation technique, which contributes to the mitigation of the interference problems. As WPs have lower sidelobes compared with sinusoidal carriers, this system is very effective in reducing the problem of inter-carrier interference. Of course, like any CDMA system, the system can suppress a given amount of interference. This paper considers an interference suppression scheme which will enhance the performance of the system. The receiver employs suppression filters to mitigate the effect of narrow-band jammer interference. The framework for the system and the performance evaluation are presented in terms of the bit error rate and the outage probability over a Nakagami fading channel. Also, we investigate how the performance is influenced by various parameters, such as the number of taps of the suppression filter and the ratio of narrow-band interference bandwidth to the spread-spectrum bandwidth. Finally, the performance of the system is compared with the performance of sinusoidal based MC/MCD-CDMA system denoted Sin-MC/MCD-CDMA.
Keywords : Suppression filter, wavelet packet, multicarrier, multicode, CDMA
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Outage Probability Performance of Wavelet Packet Multirate Multicarrier Multicode CDMA System
Authors : Dr. Maryam Akho–Zahieh, Eng. khalil Saleh and Prof. Nasser Abdellatif
Abstract : Multirate (MR) communication systems, such as multicode (MCD) scheme and variable spreading length (VSL) schemes, have been considered for transmitting informations with different data rates in Multicarrier code-division multiple access (MC-CDMA) systems. In this paper, a novel system that uses the MCD scheme for MR services in WP-MC/MCD-CDMA system is presented. The Outage Probability () performance for the system was investigated by means of analytical methods and numerical results in a slow fading frequency selective Nakagami channel. The performance analysis includes the e¤ect of fading parameter, di¤erent service rates, number of users in each service rate, WPs families and their …lter length and also number of superstreams. The performance of the system was compared with that of MC/MCD-CDMA based on sinusoidal carrier. The results reveal that performance is directly proportional to the service rate, fading parameter and WPs …lter length. It is inversely proportional to the number of users and ‡uctuates with number of superstreams. Our proposed system outperforms the other systems. It is shown that considerable performance improvement can be obtained by using WPs as subcarriers.
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Effect of Narrowband Interference on the Performance of Wavelet Packets Based Multicarrier CDMA System With Decorrelating Multiuser Detector
Authors : Prof. Nasser Abdellatif and Dr. Maryam M. Akho-Zahieh
Abstract : In this paper, we study the e¤ect of narrowband interference at the performance of wavelet packets (WP) multicarrier ( MC) code division multiple access (CDMA) system that employ decorrelating multiuser detector. The bit error rate and the outage probability are derived as performance measure for three types of diversity techniques, namely selection diversity, equal gain combining and maximum ratio combining. The system performance is compared with the performances of a wavelet packet based multicarrier system employing single user detection and multicarrier system based on sinusoidal carrier employing multiuser detection. Results reveal considerable performance improvement of our proposed system over other systems.
Keywords : Multiuser, multicarrier, wavelet packets, BER, outage probability, diversity techniques, jamming
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Effect of Diversity and Filtering on the Performance of Decorrelating Multiuser Detector Combining with Wavelet Packets Multicarrier CDMA system
Authors : Dr. Maryam M. Akho-Zahieh
Abstract : Wavelet Packets (WPs), multiuser detection, diversity and suppression filters are very effective in reducing the interferences in Coded Division multiple access communication (CDMA) systems. In this paper, we analyzed a WP Multi-Carrier (MC)-CDMA system that employs decorrelating multiuser detector. This type of detector, supports a higher number of users, suppresses the multiple access interference (MAI), thus relaxes the power control requirements. Since the sinusoidal sub-carriers are replaced by WPs sub-carriers, the proposed system will have a higher immunity against multicarriers and multipath interferences compared with the system which employs a sinusoidal subcarrier. The CDMA system can suppress a given amount of interference, but if the interference signal is powerful enough, the receiver is ineffective in mitigating this problem. In this paper, the receiver employs suppression filter (SF) to mitigate the effect of narrow-band jammer interference. The performance of the system is investigated in slow fading Nakagami channel by means of three types of diversity, which are Selection Diversity, Equal Gain Combining and Maximum Ratio Combining. For these combining techniques, Bit Error Rate (BER) and outage probability performances are investigated using several fading models and diversity orders. Also, we investigate how the performance is influenced by various parameters, such as the number of taps of the SF, the ratio of narrow-band interference bandwidth to the spreadspectrum bandwidth. Finally, the system performance is compared with WP-MC/SU-CDMA system and Sinusoidal (Sin)-MC/MU-CDMA system. Results reveal considerable performance improvement of our proposed system over the other two systems
Keywords : multiuser, multicarrier, wavelet packets, bit error rate, outage probability, diversity techniques, suppression filter
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Energy, economic and environmental analysis of fuzzy logic controllers used in smart buildings
Authors : Ali M Baniyounes, Yazeed Yasin Ghadi, Maryam Mahmoud Akho Zahia, Eyad Adwan, Kalid Oliemat
Abstract : This article is divided into three parts: the first presents a simulation study of the effect of occupancy level on energy usage pattern of Engineering building of Applied Science Private university, Amman, Jordan. The simulation was created on simulation mechanism by means of EnergyPlus software and improved by using the building’s data such as building’s as built plan, occupant’s density level based on data about who utilize the building throughout operational hours, energy usage level, Heating Ventilating and air conditioning (HVAC) system, lighting and its control systems and etc. Data regarding occupancy density level estimation is used to provide the proposed controller with random number of users grounded on report were arranged by the university’s facilities operational team. The other division of this paper shows the estimated saved energy by the means of suggested advanced add-on, FUZZY-PID controlling system. The energy savings were divided into summer savings and winter savings. The third division presents economic and environmental analysis of the proposed advanced fuzzy logic controllers of smart buildings in Subtropical Jordan. The economic parameters that were used to evaluate the system economy performance are life-cycle analysis, present worth factor and system payback period. The system economic analysis was done using MATLAB software.
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Effect of Coding and Diversity on the Performance of Wavelet Packets Multicarrier Multicode CDMA System
Authors : Maryam Mahmoud Akho-Zahieh, Nasser Abdellatif
Abstract : Coding and diversity are two techniques that can be used to improve communication system performance. The aim of this paper is to compare the effect of coding and diversity on the bit error rate performance of wavelet packets-multicarrier\multicode coded division multiple access system. Two different code rates have been considered, namely, R = 1/2 and R = 1/3. In addition, three types of diversity have been discussed, which are selection diversity, equal gain combining and maximum ratio combining. This study includes the effect of code rate, the number of substreams, the diversity order, the multipath intensity profile, the Nakagami parameter, and the number of uses. The study reveals that the code rate R=1/3 outperforms the code rate R=1/2. In addition, it has been noticed that the system with coding outperform the system with diversity when the channel interference is minimal, which includes less number of path, small Nakagami parameter, and a small number of users. The system with maximum ratio combining diversity in most conditions has the best performance.
Keywords : CDMA; Convolutional Coding; Diversity; Viterbi Decoder; Wavelet
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Performance Analysis of MIMO Wavelet Packet Multicarrier Multicode CDMA System with Antenna Selection
Authors : Maryam Mahmoud Akho-Zahieh; Abdellatif, Nasser
Abstract : Performance of Multicarrier Multicode Code-Division Multiple Access (MC/MCD-CDMA) systems can be improved significantly by using Wavelet Packets (WPs) as subcarriers instead of a sinusoidal function. This is because WPs have much lower sidelobes and negligible sidelobe energy leakage compared to sinusoidal carriers; this property significantly decreases the intercarrier interference and improves the system performance. Further improvement can be achieved by utilizing multiple antennas at transmitter and receiver to construct a Multiple-Input Multiple-Output (MIMO) system. Channel hardening is the main drawback of MIMO systems. Antenna selection can be employed to reduce this problem. In this paper, we use the antenna selection in MIMO WP-MC/MCD-CDMA system. These combinations of antenna selection, MIMO, and WP in MC/MCD-CDMA improve the system performance significantly and reduce the channel hardening. The performance of the system is tested according to the outage probability and bit error rate. Two MIMO schemes on Nakagami-m fading channel are considered, which are: selective transmit /selective receive and selective transmit /maximum ratio combining receive. The study includes the effects antennas’ number, fading parameter-m, number of users, and the threshold signal to interferences plus noise ratio. The performance of the system is compared to that of MC/MCD-CDMA based on a sinusoidal carrier. The results reveal that: by increasing antennas’ number, the system performance is improved significantly, and MC/MCD-CDMA system based on WPs carriers outperforms MC/MCD-CDMA system based on a sinusoidal carrier
Keywords : Diversity, MIMO, Nakagami channel, wavelet packets
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Effect of Multirate and Suppression Filter in the Performance of Wavelet Packet Multicarrier Multicode CDMA System
Authors : Maryam M. Akho-Zahieh
Abstract : Many ways can be considered to improve the performance of Multicarrier Multicode Code-Division Multiple Access (MC\MCD-CDMA) systems. Some of them are to use: Multirates services, suppression filters, wavelet packets, diversity and others. Multirates (MR) services can be provided in MC\MCDCDMA system by varying the number of multicodes for each user according to his data rate but the processing gain of all users must be fixed. Suppression filter (SF) can improve the performance for the system by rejecting the narrow-band jammer interference. Since wavelet packets (WPs) have lower sidelobes compared with sinusoidal carriers, then systems which use WPs as subcarriers are very effective in reducing the problem of intercarrier interference Also, to reduce multiple access interference diversity techniques can be used. In this paper, the effects of MR , WPs and SF on the performance of MC\MCD-CDMA system that uses WPs as subcarrier were investigated. The system is denoted as WP-MC\MCD-CDMA system, and the study includes the effects of number of the rates, SF and its number of taps, WP family type and filter length.
Keywords : Diversity, Multirate, Suppression filter and Wavelet
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METHOD FOR THE ANALYTICAL EVALUATION OF CONVOLUTION INTEGRAL
Authors : Maryam Akhozahieh, Osama Nashwan, Nasser Abdellatif
Abstract : The convolution integral is a linear operation. Invoking the linearity property, the superposition principle is applied in this paper to obtain the convolution integral between two signals. The method depends on dividing the two signals into several segments; each has a fixed function and a finite or infinite width. Depending on the product of the segments’ number of the first signal and that of the second signal, the evaluation of the convolution integral is divided into several sectors. Within each sector, one, two, or three integrals are needed to be calculated. The number of the integrals and the limits for each one depends on the width and the edge points of the two signals’ segments involved in a particular sector. After calculating all integrals, the superposition principle is applied to find the convolution integral for a specific period. The unit step function can be applied to express the convolution integral as a single expression.
Keywords : convolution integral, linearity, superposition, unit step function.
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Narrowband Interference Suppression in Wavelet Packet Multirate Multicarrier Multicode CDMA System
Authors : Maryam Akhozahieh, Nasser Abdellatif
Abstract : Multicode (MCD) scheme can be used to transmit information with Multirates (MR) in Multicarrier Code-Division Multiple Access (MC¬CDMA) system. Since wavelet packets (WPs) have lower sidelobes compared with sinusoidal carriers, then systems which use WPs as subcarriers are very effective in reducing the problem of intercarrier interference. The CDMA can suppress a given amount of interference. To mitigate the effect of narrow¬band jammer interference, suppression filter (SF) can be used in the receiver. Also, to reduce multiple access interference diversity techniques can be used. In this paper, the bit error rate performance of a system denoted by WP¬MR¬CDMA is tested. The effects of SF type and number of taps were investigated. Also, the effect of service rates is presented.
Keywords : Multirate, Suppression filter, Wavelet Packets
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