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- Title
- Energy-efficient target coverage in heterogeneous wireless sensor networks.
- Creator
- Awada, Wael, Florida Atlantic University, Cardei, Mihaela
- Abstract/Description
-
We consider a heterogeneous wireless sensor network, which has several supernodes for data relay and a large number of energy-constrained sensor nodes that are deployed randomly to cover certain targets. Since targets are covered by many sensors, we create several cover sets that are active successively to save power. We introduce the Heterogeneous Connected Set Covers (HCSC) which aims to find at least one cover set that covers all the targets and is connected to a data-relaying supernode. A...
Show moreWe consider a heterogeneous wireless sensor network, which has several supernodes for data relay and a large number of energy-constrained sensor nodes that are deployed randomly to cover certain targets. Since targets are covered by many sensors, we create several cover sets that are active successively to save power. We introduce the Heterogeneous Connected Set Covers (HCSC) which aims to find at least one cover set that covers all the targets and is connected to a data-relaying supernode. A sensor node can participate in different set covers but the sum of energy spent in all sets is constrained by the initial energy resources of that sensor node. This is the first solution proposed for the target coverage in heterogeneous wireless sensor networks. We show that the HCSC is an NP-Complete problem and propose three distributed algorithms for it and showing simulation results to verify the proposed approaches.
Show less - Date Issued
- 2006
- PURL
- http://purl.flvc.org/fcla/dt/13342
- Subject Headings
- Wireless communication systems, Sensor networks, Wireless LANs
- Format
- Document (PDF)
- Title
- Implementation of the Sensor-MAC protocol for the JiST/SWANS simulator.
- Creator
- Tippanagoudar, Veerendra., Florida Atlantic University, Mahgoub, Imad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
In recent years, advances in wireless technologies have enabled novel applications for wireless devices. Sensor network is one such application that consists of large number of battery-operated nodes. To simulate such networks with large number of nodes, a wireless sensor network simulator that is highly scalable is vital. JiST/SWANS is one such simulator that is highly scalable. However, the JiST/SWANS MAC layer implementation of 802.11b is not suitable for sensor networks, which are energy...
Show moreIn recent years, advances in wireless technologies have enabled novel applications for wireless devices. Sensor network is one such application that consists of large number of battery-operated nodes. To simulate such networks with large number of nodes, a wireless sensor network simulator that is highly scalable is vital. JiST/SWANS is one such simulator that is highly scalable. However, the JiST/SWANS MAC layer implementation of 802.11b is not suitable for sensor networks, which are energy-constrained. Hence, our main focus is to implement the S-MAC protocol in JiST/SWANS. The S-MAC protocol allows the nodes to go to sleep and thereby it helps conserve energy. This subsequently helps the nodes to extend their effective lifetime. We validate our S-MAC protocol implementation in the JiST/SWANS through simulations.
Show less - Date Issued
- 2006
- PURL
- http://purl.flvc.org/fcla/dt/13396
- Subject Headings
- Wireless communication systems, Sensor networks, Wireless LANs
- Format
- Document (PDF)
- Title
- Indoor Localization using WiFi Wireless LANs.
- Creator
- Azandaryani, Saeid Mirzaei, Cardei, Ionut E., Graduate College
- Date Issued
- 2013-04-12
- PURL
- http://purl.flvc.org/fcla/dt/3361902
- Subject Headings
- Wireless LANs, Mobile communication systems
- Format
- Document (PDF)
- Title
- Studies on transreceive diversity schemes (including "polarization-sense" antenna diversity) for wireless communication systems.
- Creator
- Preedalumpabut, Wichean., Florida Atlantic University, Neelakanta, Perambur S., Morgera, Salvatore D., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The research addressed in this study and deliberated in the dissertation is broadly tied to finding hybrid methods of diversity compatible for modern wireless applications. The hybrid strategy advocated thereof involves a combined use of space- (antenna and polarization), frequency-, and time-diversity schemes in a judicious manner so as to realize a desirable BER versus Eb/No performance across RF links that face multipath and other unwanted EM artifacts. The underlying reason for the hybrid...
Show moreThe research addressed in this study and deliberated in the dissertation is broadly tied to finding hybrid methods of diversity compatible for modern wireless applications. The hybrid strategy advocated thereof involves a combined use of space- (antenna and polarization), frequency-, and time-diversity schemes in a judicious manner so as to realize a desirable BER versus Eb/No performance across RF links that face multipath and other unwanted EM artifacts. The underlying reason for the hybrid scheme as above is to replace multiple-antenna based transreceive diversity. Such multiple antennas would otherwise require large base station real estate and may not be compatible for hand-held (space-constrained) RF units. On the contrary, use of hybrid schemes would restrict multiple number of antennas and conserves the space. After analyzing a set of plausible techniques of hybrid diversity compatible for modern wireless techniques, a focused study has been done on polarization-sense (PS) antenna diversity scheme. Its fruitful application for indoor systems (like Bluetooth(TM)/ZigBee(TM)) against multipath effects is demonstrated via simulation and experimental studies. Further, the PS-antenna diversity is shown to offer improved BER versus Eb/N o performance in pilot channels used in CDMA2000 systems. Also, such PS-diversity is shown to help improving the GPS receiver performance under RFI/jamming environment. The technique and heuristics proposed towards the PS-antenna diversity scheme imply novel and hitherto unexplored efforts in wireless communications. Lastly the dissertation concludes summarizing the results and offers open-questions for further studies.
Show less - Date Issued
- 2004
- PURL
- http://purl.flvc.org/fcla/dt/12104
- Subject Headings
- Wireless communication systems, Antennas (Electronics)
- Format
- Document (PDF)
- Title
- Application of video error resilience techniques for mobile broadcast multicast services (MBMS).
- Creator
- Furht, Borko, Praveenkumar, Sanigepalli, Kalva, Hari
- Abstract/Description
-
With data throughput for mobile devices constantly increasing, services such as video broadcast and multicast are becoming feasible. The 3GPP (3rd Generation Partnership Project) committee is currently working on a standard for mobile broadcast and multicast services (MBMS). MBMS is expected to enable easier deployment of video and multimedia services on 3G networks. We present an overview of the standard including the proposed architecture and requirements focusing on radio aspects. We...
Show moreWith data throughput for mobile devices constantly increasing, services such as video broadcast and multicast are becoming feasible. The 3GPP (3rd Generation Partnership Project) committee is currently working on a standard for mobile broadcast and multicast services (MBMS). MBMS is expected to enable easier deployment of video and multimedia services on 3G networks. We present an overview of the standard including the proposed architecture and requirements focusing on radio aspects. We discuss the issue of video error resilience in such services that is critical to maintain consistent quality for terminals. The error resilience techniques currently used in video streamingservices are not suitable for MBMS services. We analyze the error resilience techniques that are applicable within the context of MBMS standard and present our early research in this area.
Show less - Date Issued
- 2004-12-13 - 2004-12-15
- PURL
- http://purl.flvc.org/fcla/dt/347823
- Subject Headings
- Multimedia systems., Broadcasting --Technological innovations., Wireless communication systems., Multimedia communications.
- Format
- Document (PDF)
- Title
- Diversity performance of DS-CDMA systems in multipath fading channels.
- Creator
- Efthymoglou, George P., Florida Atlantic University, Helmken, Henry, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
In this dissertation, new semi-analytical expressions for the diversity bit error rate performance of asynchronous direct sequence-code division multiple access (DS-CDMA) systems in multipath fading channels are derived. Also, the PN acquisition time of a DS system with offset frequency periods greater than the code period in a AWGN channel is measured via laboratory experiments. In Part I we consider DS-CDMA systems operating in a cellular environment with multipath reception. Multipath...
Show moreIn this dissertation, new semi-analytical expressions for the diversity bit error rate performance of asynchronous direct sequence-code division multiple access (DS-CDMA) systems in multipath fading channels are derived. Also, the PN acquisition time of a DS system with offset frequency periods greater than the code period in a AWGN channel is measured via laboratory experiments. In Part I we consider DS-CDMA systems operating in a cellular environment with multipath reception. Multipath propagation is exploited through the use of RAKE receivers. Coherent, differentially coherent and noncoherent binary demodulation schemes are considered. The multiple access interference is modeled as AWGN, conditioned on the fading statistics of the received signal. The mobile radio channel introduces selective fading, and is modeled as a tapped delay line. The amplitude of each resolvable path is statistically described by the Nakagami distribution, which is a general solution to the random vector problem that causes rapid fading. However, we assume independent but nonidentical fading along the RAKE branches. Therefore our analysis supports unequal mean powers and different amount of fading in the multipath components combined by the receiver. Also, the results can be easily extended to account for diversity from multiple antennas or coding in the generalized Nakagami multipath fading environment. In Part II we consider a land mobile satellite channel. First, a laboratory experiment is setup to evaluate the PN acquisition performance of a digital IF receiver in a AWGN channel with large Doppler offset. The digital conversion receiver uses the inherent aliasing property of sampling to realize the baseband conversion using a single analog-to-digital converter. Thereafter, digital signal processing on the I and Q samples enable for design trade-offs in the acquisition of the PN code with Doppler periods greater than the code period. Two code phase selection criterions, namely the maximum criterion and the threshold crossing criterion, are investigated and their acquisition time is measured for different frequency offsets and input IF signal to noise ratios. We also derive semi-analytical expressions for the BER performance of coherent and differentially coherent systems operating in a mobile satellite channel. In this case the channel is modeled as a multipath nonselective channel, but diversity gain can still be obtained through path diversity. This is the scenario when a signal is transmitted to all satellites in view and the received replicas are independently demodulated and combined at the receiver. Our analysis extends previous results to the case of unequal mean powers and Rice factors in the combined signals; a valid assumption if we consider that the satellites are in view at different elevation angles. Furthermore, the effect of imperfect power control in such mobile satellite DS-CDMA systems is also considered.
Show less - Date Issued
- 1997
- PURL
- http://purl.flvc.org/fcla/dt/12516
- Subject Headings
- Mobile communication systems, Wireless communication systems, Radio wave propagation
- Format
- Document (PDF)
- Title
- Performance of wireless communication systems under various data traffic density distributions.
- Creator
- Kyperountas, Spyros C., Florida Atlantic University, Aalo, Valentine A., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis is concerned with the performance analysis of mobile cellular systems under various distributions of portable users. The performance measure used is the average outage probability. Performance analysis is performed for macrocellular as well as microcellular systems, for different distributions of mobile users such as uniform, ring, and bell distribution. The outage probability is evaluated for systems with hexagonal, triangular, and square grid layouts. The effect of macroscopic...
Show moreThis thesis is concerned with the performance analysis of mobile cellular systems under various distributions of portable users. The performance measure used is the average outage probability. Performance analysis is performed for macrocellular as well as microcellular systems, for different distributions of mobile users such as uniform, ring, and bell distribution. The outage probability is evaluated for systems with hexagonal, triangular, and square grid layouts. The effect of macroscopic diversity on system performance is also considered. Finally, computer simulations are used to verify the evaluated results.
Show less - Date Issued
- 1998
- PURL
- http://purl.flvc.org/fcla/dt/15578
- Subject Headings
- Wireless communication systems, Cellular radio, Mobile communication systems
- Format
- Document (PDF)
- Title
- Performance analysis of RLP for NAK based ARQ scheme in cdma2000 wireless systems for random error channels.
- Creator
- Easo, Daniel J., Florida Atlantic University, Pandya, Abhijit S.
- Abstract/Description
-
This thesis is an effort to present the performance analysis of the RLP in cdma2000, which uses the NAK based ARQ scheme for Random Error Channels. The performance analyses is done in terms of throughput and mean extra delay, which are calculated analytically and are compared with the results generated from the simulations. As the demand for higher data rates increases over the wireless channels, this thesis studies the effect of the random errors over the different types of RLP frame formats...
Show moreThis thesis is an effort to present the performance analysis of the RLP in cdma2000, which uses the NAK based ARQ scheme for Random Error Channels. The performance analyses is done in terms of throughput and mean extra delay, which are calculated analytically and are compared with the results generated from the simulations. As the demand for higher data rates increases over the wireless channels, this thesis studies the effect of the random errors over the different types of RLP frame formats and also the performance of the NAK based ARQ mechanism used in these conditions. The simulation provides with the overall characteristics of the throughput and the mean extra delay in terms of realistic environment parameters like Eb/No and probability of packet error (Pe), based on the channel conditions.
Show less - Date Issued
- 2001
- PURL
- http://purl.flvc.org/fcla/dt/12810
- Subject Headings
- Code division multiple access, Wireless communication systems, Mobile communication systems
- Format
- Document (PDF)
- Title
- Indexed resource auction multiple access (I-RAMA): A new medium access scheme for third generation wireless networks.
- Creator
- Barrantes-Sliesarieva, Elena Gabriela., Florida Atlantic University, Ulyas, Mohammad
- Abstract/Description
-
Indexed Resource Auction Multiple Access (I-RAMA), a new medium access protocol for wireless cellular networks based on Resource Auction Multiple Access (RAMA) is presented. I-RAMA relies in variable length resource auctions, whose length depends on the time it takes the Base Station to uniquely identify the Mobile Station. This identification is done by using dynamic Base Station information about the users present in the cell at any moment. I-RAMA effectively reduces the amount of time...
Show moreIndexed Resource Auction Multiple Access (I-RAMA), a new medium access protocol for wireless cellular networks based on Resource Auction Multiple Access (RAMA) is presented. I-RAMA relies in variable length resource auctions, whose length depends on the time it takes the Base Station to uniquely identify the Mobile Station. This identification is done by using dynamic Base Station information about the users present in the cell at any moment. I-RAMA effectively reduces the amount of time spent in the resource auctions without introducing contention or excessive complexity at the Base Station. The effects of introducing data users in the system are investigated using a simulation, and it is shown that I-RAMA guarantees Quality of Service for isochronous users while maintaining a bounded delay for data users at much higher loads than RAMA.
Show less - Date Issued
- 1995
- PURL
- http://purl.flvc.org/fcla/dt/15204
- Subject Headings
- Wireless communication systems, Cellular radio, Mobile communication systems, Computer algorithms
- Format
- Document (PDF)
- Title
- Diversity techniques in direct sequence code division multiple access communication systems.
- Creator
- Ugweje, Okechukwu Clark., Florida Atlantic University, Aalo, Valentine A., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This dissertation investigates the performance of different space diversity combining techniques for the wireless mobile communication systems employing Direct Sequence-Code Division Multiple Access (DS-CDMA). It covers two research topics, all falling under the umbrella of diversity combining techniques. The first part deals with diversity reception of wideband DS-CDMA signals in which the diversity branches experience some correlation. This analysis is performed without the usual assumption...
Show moreThis dissertation investigates the performance of different space diversity combining techniques for the wireless mobile communication systems employing Direct Sequence-Code Division Multiple Access (DS-CDMA). It covers two research topics, all falling under the umbrella of diversity combining techniques. The first part deals with diversity reception of wideband DS-CDMA signals in which the diversity branches experience some correlation. This analysis is performed without the usual assumption that diversity branches are independent and hence uncorrelated. In this case, the analysis is limited to the conventional diversity techniques such as maximal ratio combining, equal gain combining and selection diversity. In particular, the effect of correlation on system performance using two correlation profiles namely, the constant and the exponential correlation profiles is explored. In the constant correlation, the correlation between adjacent antenna are equal regardless of the separation between them, while in exponential correlation, it is assumed that the level of correlation between adjacent antennas decreases as their separation increases. The second topic deals with the development of new combining techniques. Two new techniques--the Generalized Selection Diversity Combining (GSDC) and the Maximal Ratio-Selection Diversity Combining (MR-SDC)--are introduced and analyzed in this dissertation. Analytical models which can be used to evaluate the performance of these new techniques are indicated. Results show that GSDC perform significantly better than the conventional selection diversity when two or more larger signals are selected. The MR-SDC technique accounts for the possibility of using a large array of antennas and for occasions when the receiving antennas may not be collocated. Also, it is shown that for the large array of antennas, better performance is achieved when the MR-SDC is employed with the maximum number of subgroups. The figures of merit used in this dissertation are the average Bit Error Rate (BER) and the probability of outage for a given threshold probability of error. Exact and approximate expressions are derived for the average bit error probability as well as for the outage probability while accounting for the effect of multipath fading, multiple access interference and background noise.
Show less - Date Issued
- 1997
- PURL
- http://purl.flvc.org/fcla/dt/12524
- Subject Headings
- Code division multiple access, Wireless communication systems
- Format
- Document (PDF)
- Title
- Performance analysis of wireless communication systems in multipath fading environments with correlated shadowing and co-channel interference.
- Creator
- Zhang, Jingjun., Florida Atlantic University, Aalo, Valentine A., College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The performance aspects of conventional cellular (FDMA/TDMA) and CDMA systems with micro- and macroscopic diversity reception are investigated in a severe mobile communication environment which is characterized by path loss, correlated lognormal shadowing, multipath fading, background noise and interference. Under a co-channel interference-limited assumption, an exact analytical expression for the co-channel interference (CCI) probability is presented for a macroscopic diversity system with...
Show moreThe performance aspects of conventional cellular (FDMA/TDMA) and CDMA systems with micro- and macroscopic diversity reception are investigated in a severe mobile communication environment which is characterized by path loss, correlated lognormal shadowing, multipath fading, background noise and interference. Under a co-channel interference-limited assumption, an exact analytical expression for the co-channel interference (CCI) probability is presented for a macroscopic diversity system with an arbitrary number of correlated macroscopic branches. For noise-limited systems, the average bit-error-rate (BER) and outage probability performances of a narrowband mobile communication system with micro- and macrodiversity reception are evaluated. In the relevant analysis, both Nakagami and Rician fading channels are considered. When both co-channel interference and noise coexists, the results for a Nakagami fading channel show that diversity reception can be used to reduce the effects of interference while combating fading and shadowing. Micro- and macroscopic diversities are also applied to a multicell DS-CDMA system. In a conventional cellular system with macroscopic diversity, the mobile user is usually connected to the closest base station. However, a base-station selection scheme based on a least attenuation criterion is shown to provide a significant performance improvement over the conventional system. In this case, the system performance is examined in terms of BER and outage probability, while accounting for the effects of path loss, correlated shadowing, multipath fading, multiple access interference, and imperfect power control.
Show less - Date Issued
- 1999
- PURL
- http://purl.flvc.org/fcla/dt/12600
- Subject Headings
- Wireless communication systems, Code division multiple access
- Format
- Document (PDF)
- Title
- Mobility pattern-based routing algorithm for mobile ad hoc wireless networks.
- Creator
- Vyas, Nirav., Florida Atlantic University, Mahgoub, Imad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis describes routing in mobile ad hoc wireless networks. Ad hoc networks lack wired backbone to maintain routes as mobile hosts move and power is on or off. Therefore, the hosts in ad hoc networks must cooperate with each other to determine routes in a distributed manner. Routing based on a Location is a frequently used approach, where the searching space for a route is reduced to smaller zone by defining request zone and expected zone. We propose a mobility pattern based algorithm...
Show moreThis thesis describes routing in mobile ad hoc wireless networks. Ad hoc networks lack wired backbone to maintain routes as mobile hosts move and power is on or off. Therefore, the hosts in ad hoc networks must cooperate with each other to determine routes in a distributed manner. Routing based on a Location is a frequently used approach, where the searching space for a route is reduced to smaller zone by defining request zone and expected zone. We propose a mobility pattern based algorithm to reduce the overhead, then evaluate the proposed algorithm through simulation. We have implemented two mobility patterns into Location Aided Routing, namely, leading movement and random walk type mobility patterns. We have developed simulation model for each mobility pattern, using SES/Workbench. The performance is measured in terms of overhead of the network. We also discuss various routing algorithms such as dynamic source routing, zone routing protocol, associativity based routing protocol and ad hoc on demand distance vector routing.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12662
- Subject Headings
- Mobile computing, Wireless communication systems, Computer algorithms
- Format
- Document (PDF)
- Title
- Energy-efficient protocols for wireless sensor networks.
- Creator
- Du, Kemei., Florida Atlantic University, Wu, Jie
- Abstract/Description
-
This thesis describes energy-conserving techniques in wireless sensor networks. In wireless sensor networks the sensor nodes gather information and send the information to a base station periodically. Some important messages need be broadcast to all nodes. Due to the limited battery capacity in sensor nodes, energy efficiency is becoming a major challenging problem in these power-constrained networks. Chain-based protocols construct a transmission chain connecting all nodes to save energy...
Show moreThis thesis describes energy-conserving techniques in wireless sensor networks. In wireless sensor networks the sensor nodes gather information and send the information to a base station periodically. Some important messages need be broadcast to all nodes. Due to the limited battery capacity in sensor nodes, energy efficiency is becoming a major challenging problem in these power-constrained networks. Chain-based protocols construct a transmission chain connecting all nodes to save energy dissipation of data transmission. We propose a multiple-chain scheme for all-to-all broadcasting. Furthermore, we develop an energy-efficient chain-construction algorithm which uses a sequence of insertions to minimize the energy consumption along the chain. We propose an energy-based adaptive clustering protocol, in which cluster-head elections depend on not only a probabilistic model but also the remaining energy in each node. This protocol improves the life time of the network by distributing energy usage effectively among the sensor nodes.
Show less - Date Issued
- 2002
- PURL
- http://purl.flvc.org/fcla/dt/12912
- Subject Headings
- Wireless communication systems, Computer network protocols
- Format
- Document (PDF)
- Title
- A reduced overhead routing protocol for ad hoc wireless networks.
- Creator
- Ibriq, Jamil, Florida Atlantic University, Wu, Jie
- Abstract/Description
-
This document describes the Reduced Overhead Routing (ROR) protocol for use in mobile wireless ad hoc networks. The protocol is highly bandwidth-efficient. The protocol has three distinguishing features: First, it maintains, for each destination, multiple paths. Second, routing table updates are localized. Updates are initiated only when the update table is not empty and the update frequency has not exceeded a specified rate. Third, ROR uses threshold routing technique; it allows an...
Show moreThis document describes the Reduced Overhead Routing (ROR) protocol for use in mobile wireless ad hoc networks. The protocol is highly bandwidth-efficient. The protocol has three distinguishing features: First, it maintains, for each destination, multiple paths. Second, routing table updates are localized. Updates are initiated only when the update table is not empty and the update frequency has not exceeded a specified rate. Third, ROR uses threshold routing technique; it allows an intermediate node to deliver data packet via a longer sub-optimal route that is within the distance. To prevent frequent updates, at most one update is initiated every predefined period of time. A node transmits each update with propagation radius that is determined on the basis of node's network region using a novel probabilistic technique. Threshold routing and localized probabilistic updates greatly reduce routing overhead and network congestion and improve bandwidth efficiency.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/12703
- Subject Headings
- Mobile computing, Computer networks, Wireless communication systems
- Format
- Document (PDF)
- Title
- EM polarization measurement campaign and its applications.
- Creator
- Pollard, Ritsuko Hamahata, Florida Atlantic University, Helmken, Henry, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Due to a continuous growth of demand in voice and data communications for wireless systems, there is an ongoing challenge to design improved radiowave communication links. Polarization is one of the key properties of electromagnetic waves used in wireless communication and is the least studied in a scattering environment. A detailed understanding of how signals become de-polarized can improve the propagation models and can lead to more accurate propagation predictions and possibly new...
Show moreDue to a continuous growth of demand in voice and data communications for wireless systems, there is an ongoing challenge to design improved radiowave communication links. Polarization is one of the key properties of electromagnetic waves used in wireless communication and is the least studied in a scattering environment. A detailed understanding of how signals become de-polarized can improve the propagation models and can lead to more accurate propagation predictions and possibly new applications in the use of polarization. Potential beneficiaries of a system design using multi-dimensional polarization constellations to provide maximum polarization separation might include inter-satellite links, WLAN, LEO satellites [BSPP92] [IPLJ81] [SIKA98] and other systems operating in an environment where depolarization is insignificant. To examine the applicability of polarization in wireless communication systems, polarization field measurements were conducted, and the results and analysis are presented in this dissertation. Based on the analysis, a statistical model that characterizes polarization in relation to Poincare sphere is developed and presented. Design and implementation of an N-constellation diversity scheme that provides maximum polarization separation distance is presented. Furthermore, a decision-making algorithm is utilized for detection of the received electric field that selects the minimum Euclidian distance between the transmitter and receivers in Stokes space. The scenario is simulated for an N-constellation scheme for N = 2, 3, 4 based on the design scheme utilizing the developed statistical model and decision-making algorithm and is used to evaluate the detectability and performance comparison for various values of standard deviations.
Show less - Date Issued
- 2004
- PURL
- http://purl.flvc.org/fau/fd/FADT12089
- Subject Headings
- Electromagnetic waves--Polarization, Wireless communication systems
- Format
- Document (PDF)
- Title
- Simulation-based performance evaluation of AODV routing protocol for ad hoc mobile wireless networks.
- Creator
- Suryaprasad, Deepa., Florida Atlantic University, Ilyas, Mohammad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
An ad hoc wireless network is a network composed of mobile communication devices, which is designed to provide communication capability to satisfy the need of a temporary nature in an infrastructure-less environment. A routing protocol is necessary in ad hoc networks to ensure effective communication among nodes. This thesis presents a simulation-based study on the performance evaluation of Ad hoc on-demand distance vector (AODV) routing protocol, which is one of the core routing protocols...
Show moreAn ad hoc wireless network is a network composed of mobile communication devices, which is designed to provide communication capability to satisfy the need of a temporary nature in an infrastructure-less environment. A routing protocol is necessary in ad hoc networks to ensure effective communication among nodes. This thesis presents a simulation-based study on the performance evaluation of Ad hoc on-demand distance vector (AODV) routing protocol, which is one of the core routing protocols being promoted by the Mobile Ad Hoc Networking (MANET) group of the Internet Engineering Task Force. An event-advanced simulation program was developed in C++ to simulate the ad hoc wireless network implementing the AODV protocol. The performance metrics evaluated were throughput, average delay, route acquisition time and routing overhead. The network traffic was monitored in terms of the data packets created and successfully delivered within the simulation time. A discussion on the effect of different network parameters such as the mobility of the nodes, the number of nodes in the network, the size of the network and the data packet size on the performance characteristics of AODV protocol is also presented.
Show less - Date Issued
- 2003
- PURL
- http://purl.flvc.org/fcla/dt/12989
- Subject Headings
- Computer network protocols, Wireless communication systems
- Format
- Document (PDF)
- Title
- Design and implementation of an energy model for JiST/SWANS simulator.
- Creator
- Sutaria, Trishla., Florida Atlantic University, Mahgoub, Imad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Wireless sensor networks are one of the first real world examples of pervasive computing, the notion that small, smart, and cheap sensing and computing devices will eventually permeate the environment. Sensor networks consist of very large number of energy constrained nodes and to properly evaluate these networks a scalable ad-hoc wireless network simulator with an energy model is needed. Since most of the existing simulators have been designed for ad-hoc network with low scalability they can...
Show moreWireless sensor networks are one of the first real world examples of pervasive computing, the notion that small, smart, and cheap sensing and computing devices will eventually permeate the environment. Sensor networks consist of very large number of energy constrained nodes and to properly evaluate these networks a scalable ad-hoc wireless network simulator with an energy model is needed. Since most of the existing simulators have been designed for ad-hoc network with low scalability they can not be used to accurately simulate sensor networks. The JiST/SWANS simulator is one of the newer simulators that has been developed by Cornell University for simulating ad-hoc networks and is highly scalable which makes it appropriate for use in evaluating sensor networks. Since this simulator lack energy model our objective is to design and implement an energy model for JiST/SWANS so that it can adequately and accurately calculate the amount of energy consumption in the simulation of sensor networks.
Show less - Date Issued
- 2005
- PURL
- http://purl.flvc.org/fcla/dt/13275
- Subject Headings
- Sensor networks, Wireless LANs, Computer network protocols, Wireless communication systems
- Format
- Document (PDF)
- Title
- Location-based services utilizing XML technology.
- Creator
- Orzel, Russell Scott., Florida Atlantic University, Mahgoub, Imad, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
As Wireless appliances become more common place we are beginning to experience multiple problems. We are experiencing interoperability problems related to devices' capabilities in relation to applications, along with network/application services limitations for understanding the diversity among these devices. In this thesis the issues related to Location Discovery, Location Management and Device capabilities are discussed. Solutions based on current technologies, including Triangulation and...
Show moreAs Wireless appliances become more common place we are beginning to experience multiple problems. We are experiencing interoperability problems related to devices' capabilities in relation to applications, along with network/application services limitations for understanding the diversity among these devices. In this thesis the issues related to Location Discovery, Location Management and Device capabilities are discussed. Solutions based on current technologies, including Triangulation and GPS, are discussed for Location Management along with the concepts of Location Tracking and Location Modeling for increasing the effectiveness of Location Management technologies. Finally an XML based Language is presented which affords generality for User to Network and Network to User communication for the many wireless devices.
Show less - Date Issued
- 2001
- PURL
- http://purl.flvc.org/fcla/dt/12761
- Subject Headings
- XML (Document markup language), Wireless communication systems, Wireless Internet
- Format
- Document (PDF)
- Title
- Analysis of quality of service (QoS) in WiMAX networks.
- Creator
- Talwalkar, Rohit., College of Engineering and Computer Science, Florida Atlantic University, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
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In last few years there has been significant growth in the area of wireless communication. Quality of Service (QoS) has become an important consideration for supporting variety of applications that utilize the network resources. These applications include voice over IP, multimedia services, like, video streaming, video conferencing etc. IEEE 802.16/WiMAX is a new network which is designed with quality of service in mind. This thesis focuses on analysis of quality of service as implemented by...
Show moreIn last few years there has been significant growth in the area of wireless communication. Quality of Service (QoS) has become an important consideration for supporting variety of applications that utilize the network resources. These applications include voice over IP, multimedia services, like, video streaming, video conferencing etc. IEEE 802.16/WiMAX is a new network which is designed with quality of service in mind. This thesis focuses on analysis of quality of service as implemented by the WiMAX networks. First, it presents the details of the quality of service architecture in WiMAX network. In the analysis, a WiMAX module developed based on popular network simulator ns-2, is used. Various real life scenarios like voice call, video streaming are setup in the simulation environment. Parameters that indicate quality of service, such as, throughput, packet loss, average jitter and average delay, are analyzed for different types of service flows as defined in WiMAX. Results indicate that better quality of service is achieved by using service flows designed for specific applications.
Show less - Date Issued
- 2008
- PURL
- http://purl.flvc.org/fcla/flaent/EN00154040/68_2/98p0143h.pdf, http://purl.flvc.org/FAU/58012
- Subject Headings
- Wireless communication systems, Broadband communication systems, Wireless LANs, Design and construction, Computer networks, Management, Quality control
- Format
- Document (PDF)
- Title
- Impact of interference on connectivity and outage performances in wireless communication networks: interference-based channel models.
- Creator
- Mukasa, Constantine, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
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In recent years, a plethora of wireless applications such as Bluetooth and Ultra-wide band (UWB) radio have emerged. This drastic increase has overly congested the spectrum. So, new networks such as cognitive radios that can solve the spectrum congestion have emerged. But in such networks, interference is introduced at the physical layer. We study and develop an interference model capable of capturing the intrinsic characteristics of the coexistence of such wireless applications. We...
Show moreIn recent years, a plethora of wireless applications such as Bluetooth and Ultra-wide band (UWB) radio have emerged. This drastic increase has overly congested the spectrum. So, new networks such as cognitive radios that can solve the spectrum congestion have emerged. But in such networks, interference is introduced at the physical layer. We study and develop an interference model capable of capturing the intrinsic characteristics of the coexistence of such wireless applications. We investigate the effect of interference using device isolation probability or outage probability in presence Rayleigh and Nakagami-m fading at the physical layer and the impact of lognormal shadowing. We assume that the devices are either deterministically placed or randomly distributed according to a Poisson point process. We derive explicit expressions for the isolation probability and outage probability that give insight into how these channel impairments affect communication in these applications. We use computer simulations to validate our analytical results.
Show less - Date Issued
- 2013
- PURL
- http://purl.flvc.org/fcla/dt/3362551
- Subject Headings
- Wireless communication systems, Technological innovations, Wireless communication systems, Mathematical models, Orthogonal frequency division multiplexing
- Format
- Document (PDF)