This paper studies the parametrization of speech using linear predictive (LP) analysis and its ap... more This paper studies the parametrization of speech using linear predictive (LP) analysis and its application to speaker identification. The task of speaker classification is realized using multilayer perceptron. The system is evaluated on speaker set for speaker identification. The system is also tested with cepstral and reflection coefficients, and the results obtained are compared
The effects of the multi‐beam directional antennas on the performance of a new wireless TDMA∕FDD ... more The effects of the multi‐beam directional antennas on the performance of a new wireless TDMA∕FDD MAC system are presented. Directional antennas intrinsically enable development of the SDMA systems and allow transmitting and receiving signals simultaneously at the ...
Nowadays, the importance of wireless technologies is increasing rapidly. Next generation wireless... more Nowadays, the importance of wireless technologies is increasing rapidly. Next generation wireless networks concept proposes a heterogeneous structure, consists of different wireless technologies, in order to provide quality of service (QoS) supported and cost efficient connections at anywhere and anytime. Since different wireless technologies overlap with each other, one of the most challenging topics for next generation wireless networks is handoff. Several parameters, pertaining to user/application requirements and network conditions, such as; data rate, service cost, network latency, speed of mobile, and etc. must be considered in handoff process of heterogeneous networks along with RSSI information. In this paper, an adaptive fuzzy logic based vertical handoff decision making algorithm is presented for wireless overlay networks which consist of GSM/GPRS/Wi-Fi/UMTS/WiMAX technologies. Data rate, monetary cost, speed of mobile, battery level and RSSI parameters are considered as inputs of the proposed fuzzy based system. The results show that, proposed adaptive fuzzy based algorithm can provide enhanced outcomes for both user and network.
Summary form only given. Controller area networks (CAN) are currently employed in many distribute... more Summary form only given. Controller area networks (CAN) are currently employed in many distributed real-time control applications in industrial environments. The CAN protocol based on a CSMA/CD+CR access mechanism with the use of priorities is a serial communication protocol and is used to support distributed real-time control and multiplexing. CAN-based distributed control systems have two main problems. They are the size of distributed area and the need for communication with other LANs and with remote CAN segments. A straightforward solution is to use interworking devices with wireless support to extend CAN segments, exploiting an IEEE 802.11 WLAN that is low cost technology with high data rates. This research study aims at designing and implementing such an interworking device called a wireless internetworking unit (WIU) that is capable of connecting remote CAN 2.0A nodes over IEEE 802.11b WLAN using an encapsulation method. Computer modeling and simulation of the proposed approach realized using OPNET Modeler and analysis of the simulation results obtained are also presented.
Traditional wireless networking solutions are almost all unsuitable for multimedia applications w... more Traditional wireless networking solutions are almost all unsuitable for multimedia applications whose QoS requirements may differ from each other diversely. Main inspiration of WATM, promising ideal transmission of different traffics such as voice, data and video together over wireless medium, is to implement high bit rate and QoS guaranteed data transfer, which is already well realized by ATM technology over wired infrastructure. An effective MAC protocol must be employed to provide multimedia applications with QoS guaranteed data transfer over the shared wireless medium that naturally is error-prone and has low bandwidth capacity. In this paper, we propose a new MAC protocol with a QoS guarantee based scheduling algorithm for WATM networks. It fairly maintains QoS requirements of all real-time wireless multimedia applications. Computer modeling and simulation of a WATM network with the proposed approach to provide CBR, VBR, ABR and UBR ATM services are also realized using a commercially available tool named OPNET Modeler. Preliminary simulation results obtained are presented, including comparisons with those of a WATM counterpart employing a well-known MAC protocol.
Due to very sensitive and crucial nature of the collected data, any Wireless Sensor Network (WSN)... more Due to very sensitive and crucial nature of the collected data, any Wireless Sensor Network (WSN) has to handle efficiently securing it as well as to employ energy-aware and delay-sensitive algorithms in its all layers from application to the physical. These key topics strictly related ...
Handoff decision making is one of the most important topics in wireless heterogeneous networks ar... more Handoff decision making is one of the most important topics in wireless heterogeneous networks architecture as there are many parameters which have to be considered when triggering handoff and selecting suitable access point. More intelligent approaches which reckon user profiles, application requirements, and network conditions must be improved so that desired performance results for both user and network could be provided. In this paper we introduce a new adaptive vertical handoff decision making algorithm in which fuzzy membership functions are optimized by means of genetic algorithm. Genetic algorithm is an adaptive search technique based on natural selection and genetic rules. In addition to that, it takes places in various scientific applications and can be used to adjust the membership functions in fuzzy systems. The purpose of the study is to adjust the shape of fuzzy membership functions, properly, using genetic algorithm in order to achieve optimum handoff performance. The results show that, compared to the several different algorithms performance of the proposed approach with genetic algorithm is significantly improved for both user and network in terms of number of handoff while the other requirements are still satisfied.
This paper introduces a demo application toolkit, implemented using Matlab GUI, for teaching conv... more This paper introduces a demo application toolkit, implemented using Matlab GUI, for teaching convolutional coding techniques employed in wireless communications. In this study presented, Viterbi decoding algorithm, log-MAP and SOVA Turbo decoding algorithms are performed using Matlab software. With the toolkit developed, an example image transfer application has been carried out for comparative performance analysis of these techniques. Using the
AbstractOne of the biggest drawbacks of the wireless environment is the limited bandwidth. Howev... more AbstractOne of the biggest drawbacks of the wireless environment is the limited bandwidth. However, the users sharing this limited bandwidth have been increasing considerably. SDMA technique which entails using directional antennas allows to ...
ABSTRACT In this study, a CAN model has been constituted using the OPNET software which is based ... more ABSTRACT In this study, a CAN model has been constituted using the OPNET software which is based on discrete event simulation technique. Its evaluation in reliable real-time communication environments has been realized using the obtained simulation results. Performance assessment of the network model has been carried out depending upon such parameters as end-to-end message delay, throughput, and packet loss ratio.
The CAN is used in many distributed real-time control applications in industrial environments whe... more The CAN is used in many distributed real-time control applications in industrial environments where basically there are two main problems. These are namely the size of distributed area and the need for commu nication with other LANs and with independent CAN segments. A practical solution is to use interworking devices with wireless support to extend CAN segments, utilizing an IEEE 802.11b WLAN. Main objective of this research work is to design and implement su ch an interworking device called Wireless Interworking Unit enabling remote CAN2.0A nodes to communicate over IEEE 802.11b WLAN using encapsulation method. Computer modeling and simulation of the new approach are realized by using OPNET Modeler and analysis of the simulation results obtained are also presented.
... from one GSM base station to another one that is serving in the adjacent cell is called ... I... more ... from one GSM base station to another one that is serving in the adjacent cell is called ... In addition to RSSI, such parameters as SNR, frame error rate or packet loss ratio, base station ... is introduced in [3]. Handoff decision metrics used in the algorithm are: RSSI, the ratio of the ...
Currently, single wireless network technology can not satisfy all of the requirements of mobile u... more Currently, single wireless network technology can not satisfy all of the requirements of mobile users at anywhere and anytime. Due to such requirements as QoS provision, cost efficiency, mobility, and etc. integration of different wireless technologies is necessary and there is, in turn, an urgent demand to develop vertical handoff approaches that enable mobile terminals to seamlessly roam between wireless networks overlap with each other. In the quest for efficient handoff especially in the heterogeneous environment, various handoff decision making techniques have been proposed in the literature. In this paper, an adaptive fuzzy logic based vertical handoff decision making algorithm and an Adaptive Network Fuzzy Inference System (ANFIS) based vertical handoff decision making algorithm are developed for wireless heterogeneous networks which consist of GSM/GPRS, Wi-Fi, UMTS and WiMAX technologies. The parameters data rate, monetary cost and RSSI information are processed as inputs of the developed fuzzy based system. According to these parameters, an output value APCV which is utilized to chose the best candidate access point, is produced. Training data of ANFIS based vertical handoff decision making algorithm is obtained from the developed fuzzy based handoff algorithm and human expert. The results show that, compared to the typical fuzzy based algorithm, proposed ANFIS algorithm can provide enhanced outcomes for both user and network in terms of number of handoff, decision process time, and hardware implementation.
This paper studies the parametrization of speech using linear predictive (LP) analysis and its ap... more This paper studies the parametrization of speech using linear predictive (LP) analysis and its application to speaker identification. The task of speaker classification is realized using multilayer perceptron. The system is evaluated on speaker set for speaker identification. The system is also tested with cepstral and reflection coefficients, and the results obtained are compared
The effects of the multi‐beam directional antennas on the performance of a new wireless TDMA∕FDD ... more The effects of the multi‐beam directional antennas on the performance of a new wireless TDMA∕FDD MAC system are presented. Directional antennas intrinsically enable development of the SDMA systems and allow transmitting and receiving signals simultaneously at the ...
Nowadays, the importance of wireless technologies is increasing rapidly. Next generation wireless... more Nowadays, the importance of wireless technologies is increasing rapidly. Next generation wireless networks concept proposes a heterogeneous structure, consists of different wireless technologies, in order to provide quality of service (QoS) supported and cost efficient connections at anywhere and anytime. Since different wireless technologies overlap with each other, one of the most challenging topics for next generation wireless networks is handoff. Several parameters, pertaining to user/application requirements and network conditions, such as; data rate, service cost, network latency, speed of mobile, and etc. must be considered in handoff process of heterogeneous networks along with RSSI information. In this paper, an adaptive fuzzy logic based vertical handoff decision making algorithm is presented for wireless overlay networks which consist of GSM/GPRS/Wi-Fi/UMTS/WiMAX technologies. Data rate, monetary cost, speed of mobile, battery level and RSSI parameters are considered as inputs of the proposed fuzzy based system. The results show that, proposed adaptive fuzzy based algorithm can provide enhanced outcomes for both user and network.
Summary form only given. Controller area networks (CAN) are currently employed in many distribute... more Summary form only given. Controller area networks (CAN) are currently employed in many distributed real-time control applications in industrial environments. The CAN protocol based on a CSMA/CD+CR access mechanism with the use of priorities is a serial communication protocol and is used to support distributed real-time control and multiplexing. CAN-based distributed control systems have two main problems. They are the size of distributed area and the need for communication with other LANs and with remote CAN segments. A straightforward solution is to use interworking devices with wireless support to extend CAN segments, exploiting an IEEE 802.11 WLAN that is low cost technology with high data rates. This research study aims at designing and implementing such an interworking device called a wireless internetworking unit (WIU) that is capable of connecting remote CAN 2.0A nodes over IEEE 802.11b WLAN using an encapsulation method. Computer modeling and simulation of the proposed approach realized using OPNET Modeler and analysis of the simulation results obtained are also presented.
Traditional wireless networking solutions are almost all unsuitable for multimedia applications w... more Traditional wireless networking solutions are almost all unsuitable for multimedia applications whose QoS requirements may differ from each other diversely. Main inspiration of WATM, promising ideal transmission of different traffics such as voice, data and video together over wireless medium, is to implement high bit rate and QoS guaranteed data transfer, which is already well realized by ATM technology over wired infrastructure. An effective MAC protocol must be employed to provide multimedia applications with QoS guaranteed data transfer over the shared wireless medium that naturally is error-prone and has low bandwidth capacity. In this paper, we propose a new MAC protocol with a QoS guarantee based scheduling algorithm for WATM networks. It fairly maintains QoS requirements of all real-time wireless multimedia applications. Computer modeling and simulation of a WATM network with the proposed approach to provide CBR, VBR, ABR and UBR ATM services are also realized using a commercially available tool named OPNET Modeler. Preliminary simulation results obtained are presented, including comparisons with those of a WATM counterpart employing a well-known MAC protocol.
Due to very sensitive and crucial nature of the collected data, any Wireless Sensor Network (WSN)... more Due to very sensitive and crucial nature of the collected data, any Wireless Sensor Network (WSN) has to handle efficiently securing it as well as to employ energy-aware and delay-sensitive algorithms in its all layers from application to the physical. These key topics strictly related ...
Handoff decision making is one of the most important topics in wireless heterogeneous networks ar... more Handoff decision making is one of the most important topics in wireless heterogeneous networks architecture as there are many parameters which have to be considered when triggering handoff and selecting suitable access point. More intelligent approaches which reckon user profiles, application requirements, and network conditions must be improved so that desired performance results for both user and network could be provided. In this paper we introduce a new adaptive vertical handoff decision making algorithm in which fuzzy membership functions are optimized by means of genetic algorithm. Genetic algorithm is an adaptive search technique based on natural selection and genetic rules. In addition to that, it takes places in various scientific applications and can be used to adjust the membership functions in fuzzy systems. The purpose of the study is to adjust the shape of fuzzy membership functions, properly, using genetic algorithm in order to achieve optimum handoff performance. The results show that, compared to the several different algorithms performance of the proposed approach with genetic algorithm is significantly improved for both user and network in terms of number of handoff while the other requirements are still satisfied.
This paper introduces a demo application toolkit, implemented using Matlab GUI, for teaching conv... more This paper introduces a demo application toolkit, implemented using Matlab GUI, for teaching convolutional coding techniques employed in wireless communications. In this study presented, Viterbi decoding algorithm, log-MAP and SOVA Turbo decoding algorithms are performed using Matlab software. With the toolkit developed, an example image transfer application has been carried out for comparative performance analysis of these techniques. Using the
AbstractOne of the biggest drawbacks of the wireless environment is the limited bandwidth. Howev... more AbstractOne of the biggest drawbacks of the wireless environment is the limited bandwidth. However, the users sharing this limited bandwidth have been increasing considerably. SDMA technique which entails using directional antennas allows to ...
ABSTRACT In this study, a CAN model has been constituted using the OPNET software which is based ... more ABSTRACT In this study, a CAN model has been constituted using the OPNET software which is based on discrete event simulation technique. Its evaluation in reliable real-time communication environments has been realized using the obtained simulation results. Performance assessment of the network model has been carried out depending upon such parameters as end-to-end message delay, throughput, and packet loss ratio.
The CAN is used in many distributed real-time control applications in industrial environments whe... more The CAN is used in many distributed real-time control applications in industrial environments where basically there are two main problems. These are namely the size of distributed area and the need for commu nication with other LANs and with independent CAN segments. A practical solution is to use interworking devices with wireless support to extend CAN segments, utilizing an IEEE 802.11b WLAN. Main objective of this research work is to design and implement su ch an interworking device called Wireless Interworking Unit enabling remote CAN2.0A nodes to communicate over IEEE 802.11b WLAN using encapsulation method. Computer modeling and simulation of the new approach are realized by using OPNET Modeler and analysis of the simulation results obtained are also presented.
... from one GSM base station to another one that is serving in the adjacent cell is called ... I... more ... from one GSM base station to another one that is serving in the adjacent cell is called ... In addition to RSSI, such parameters as SNR, frame error rate or packet loss ratio, base station ... is introduced in [3]. Handoff decision metrics used in the algorithm are: RSSI, the ratio of the ...
Currently, single wireless network technology can not satisfy all of the requirements of mobile u... more Currently, single wireless network technology can not satisfy all of the requirements of mobile users at anywhere and anytime. Due to such requirements as QoS provision, cost efficiency, mobility, and etc. integration of different wireless technologies is necessary and there is, in turn, an urgent demand to develop vertical handoff approaches that enable mobile terminals to seamlessly roam between wireless networks overlap with each other. In the quest for efficient handoff especially in the heterogeneous environment, various handoff decision making techniques have been proposed in the literature. In this paper, an adaptive fuzzy logic based vertical handoff decision making algorithm and an Adaptive Network Fuzzy Inference System (ANFIS) based vertical handoff decision making algorithm are developed for wireless heterogeneous networks which consist of GSM/GPRS, Wi-Fi, UMTS and WiMAX technologies. The parameters data rate, monetary cost and RSSI information are processed as inputs of the developed fuzzy based system. According to these parameters, an output value APCV which is utilized to chose the best candidate access point, is produced. Training data of ANFIS based vertical handoff decision making algorithm is obtained from the developed fuzzy based handoff algorithm and human expert. The results show that, compared to the typical fuzzy based algorithm, proposed ANFIS algorithm can provide enhanced outcomes for both user and network in terms of number of handoff, decision process time, and hardware implementation.
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