Current Search: Signal processing--Digital techniques (x)
View All Items
(1 - 20 of 24)
Pages
- Title
- Array processing techniques for frequency hopping multiple frequency shift keying long-range communications.
- Creator
- Bernault, Emmanuel Pierre., Florida Atlantic University, Schock, Steven G.
- Abstract/Description
-
Underwater communication is an important component of Autonomous Underwater Vehicle (AUV) operations. Communicating underwater is limited to very low communication rates without the use of processing techniques that mitigate the influence of the acoustic channel. This thesis develops array processing techniques for frequency hopping and multiple frequency shift keying to achieve long range, reliable high speed communications. The thesis makes the comparison between two techniques for...
Show moreUnderwater communication is an important component of Autonomous Underwater Vehicle (AUV) operations. Communicating underwater is limited to very low communication rates without the use of processing techniques that mitigate the influence of the acoustic channel. This thesis develops array processing techniques for frequency hopping and multiple frequency shift keying to achieve long range, reliable high speed communications. The thesis makes the comparison between two techniques for calculating beamforming coefficients: a coherent Least Mean Square (LMS) adaptive filter and a non-coherent LMS. An Equal Gain Combiner (EGC) and a Maximum Likelihood (ML) were used to determine the performance of the coherent and non-coherent LMS. The results show that by using the coherent LMS, the ML or the EGC, communications at rates of 493 bit per second (bps) and 370bps can be achieved with no frame error at 5km in 40 feet of water using 16.3kHz of bandwidth centered at 25kHz.
Show less - Date Issued
- 2002
- PURL
- http://purl.flvc.org/fcla/dt/12914
- Subject Headings
- Underwater acoustics, Signal processing--Digital techniques
- Format
- Document (PDF)
- Title
- Digital techniques for electronic countermeasures signal-processing.
- Creator
- Lopez, Juan J., Florida Atlantic University, Erdol, Nurgun, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The purpose of this thesis is to show the use of digital techniques for Electronic Countermeasures (ECM) signal processing. The main objective is the use of only digital circuitry for the processing of the ECM signals. A recent design of an ECM controller called the Oscillator Waveform Controller (OWC) follows this philosophy. The OWC digitally controls the generation of its nine jamming modes plus the modes generated by the other ECM modules within the ECM system. The use of advance...
Show moreThe purpose of this thesis is to show the use of digital techniques for Electronic Countermeasures (ECM) signal processing. The main objective is the use of only digital circuitry for the processing of the ECM signals. A recent design of an ECM controller called the Oscillator Waveform Controller (OWC) follows this philosophy. The OWC digitally controls the generation of its nine jamming modes plus the modes generated by the other ECM modules within the ECM system. The use of advance microcircuitry technology allows the OWC the capability of controlling all the parameters within an ECM system. The most desirable feature of the OWC is the use of high level communications for programming ECM mode parameters from an external computer or terminal and digitally storing this parameters upon removal of power.
Show less - Date Issued
- 1987
- PURL
- http://purl.flvc.org/fcla/dt/14427
- Subject Headings
- Electronic countermeasures, Signal processing--Digital techniques
- Format
- Document (PDF)
- Title
- Wavelet transform-based digital signal processing.
- Creator
- Basbug, Filiz., Florida Atlantic University, Erdol, Nurgun, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This study deals with applying the wavelet transform to mainly two different areas of signal processing: adaptive signal processing, and signal detection. It starts with background information on the theory of wavelets with an emphasis on the multiresolution representation of signals by the wavelet transform in Chapter 1. Chapter 2 begins with an overview of adaptive filtering in general and extends it to transform domain adaptive filtering. Later in the chapter, a novel adaptive filtering...
Show moreThis study deals with applying the wavelet transform to mainly two different areas of signal processing: adaptive signal processing, and signal detection. It starts with background information on the theory of wavelets with an emphasis on the multiresolution representation of signals by the wavelet transform in Chapter 1. Chapter 2 begins with an overview of adaptive filtering in general and extends it to transform domain adaptive filtering. Later in the chapter, a novel adaptive filtering architecture using the wavelet transform is introduced. The performance of this new structure is evaluated by using the LMS algorithm with variations in step size. As a result of this study, the wavelet transform based adaptive filter is shown to reduce the eigenvalue ratio, or condition number, of the input signal. As a result, the new structure is shown to have faster convergence, implying an improvement in the ability to track rapidly changing signals. Chapter 3 deals with signal detection with the help of the wavelet transform. One scheme studies signal detection by projecting the input signal onto different scales. The relationship between this approach and that of matched filtering is established. Then the effect of different factors on signal detection with the wavelet transform is examined. It is found that the method is robust in the presence of white noise. Also, the wavelets are analyzed as eigenfunctions of a certain random process, and how this gives way to optimal receiver design is shown. It is further demonstrated that the design of an optimum receiver leads to the wavelet transform based adaptive filter structure described in Chapter 2.
Show less - Date Issued
- 1993
- PURL
- http://purl.flvc.org/fcla/dt/12354
- Subject Headings
- Wavelets (Mathematics), Signal processing--Digital techniques
- Format
- Document (PDF)
- Title
- Design of a frequency shift keying array receiver for the acoustic modem.
- Creator
- Boubli, Cecile., Florida Atlantic University, LeBlanc, Lester R.
- Abstract/Description
-
Currently, our acoustic modems are used to communicate underwater to Autonomous Underwater Vehicles AUVs. These modems have only one sensor and can transmit at low data rates (from 200 to 1200 bits per second) using Frequency Shift Keying (FSK) modulation. A two-dimensional array receiver (MillsCross) has been developed to receive underwater signals with more reliability, at a higher data rate (about 30,000 bits per second). This array has been designed to operate with Phase Shift Keying...
Show moreCurrently, our acoustic modems are used to communicate underwater to Autonomous Underwater Vehicles AUVs. These modems have only one sensor and can transmit at low data rates (from 200 to 1200 bits per second) using Frequency Shift Keying (FSK) modulation. A two-dimensional array receiver (MillsCross) has been developed to receive underwater signals with more reliability, at a higher data rate (about 30,000 bits per second). This array has been designed to operate with Phase Shift Keying modulated signals. The purpose of this thesis is to design and implement a signal processing software to demodulate and decode FSK signals acquired by the MillsCross. By taking advantage of the spatial gain of the MillsCross receiver array, higher reliability and longer ranges are expected using FSK, in addition to achieving compatibility between the two systems. This software includes a robust synchronization scheme, a spatial and an equalizing filter, a time-window self-adjusting process and the error control decoding.
Show less - Date Issued
- 2000
- PURL
- http://purl.flvc.org/fcla/dt/15788
- Subject Headings
- Underwater acoustics, Modems, Signal processing--Digital techniques
- Format
- Document (PDF)
- Title
- Multi-pulse excited linear prediction for synthesizing the guitar.
- Creator
- Leeds, David Scott., Florida Atlantic University, Erdol, Nurgun, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
In this paper we propose using parametric modeling by employing a Multi-Pulse Excited Linear Predictive Coded (MPE-LPC) filter to synthesize the guitar. First we introduce different methods for sound synthesis. A detailed discussion including the derivation of LPC and MPE presented. Then we study the impulse and steady state response of the guitar signal. An implementation of the MPE-LPC method to model the guitar is covered in detail and opportunities to improve the compression ratio are...
Show moreIn this paper we propose using parametric modeling by employing a Multi-Pulse Excited Linear Predictive Coded (MPE-LPC) filter to synthesize the guitar. First we introduce different methods for sound synthesis. A detailed discussion including the derivation of LPC and MPE presented. Then we study the impulse and steady state response of the guitar signal. An implementation of the MPE-LPC method to model the guitar is covered in detail and opportunities to improve the compression ratio are discussed. We then present simulation results with a set of fixed parameters, which are used as a benchmark to observe performance trade-offs by varying the model parameters to improve the compression ratio. Finally, we discuss limitations of the modeling algorithm for use with wide-band transient musical sounds and possible applications of the MPE-LPC model as a method to dynamically calculate samples for use with wavetable synthesis of steady state sounds.
Show less - Date Issued
- 2001
- PURL
- http://purl.flvc.org/fcla/dt/12759
- Subject Headings
- Computer music, Electric guitar, Signal processing--Digital techniques
- Format
- Document (PDF)
- Title
- Implementation and representation of the discrete wavelet transform.
- Creator
- Efthymoglou, George P., Florida Atlantic University, Erdol, Nurgun
- Abstract/Description
-
This thesis presents a comprehensive analysis of a relatively new transform for discrete time signals, called the Discrete Wavelet Transform (DWT). We find how this transform is connected with the already existing theory of perfect reconstruction filter banks and the recently introduced theory of multiresolution analysis. We use the conditions obtained from these two theories in order to understand the construction of wavelet filters, which also generate continuous functions that prove to...
Show moreThis thesis presents a comprehensive analysis of a relatively new transform for discrete time signals, called the Discrete Wavelet Transform (DWT). We find how this transform is connected with the already existing theory of perfect reconstruction filter banks and the recently introduced theory of multiresolution analysis. We use the conditions obtained from these two theories in order to understand the construction of wavelet filters, which also generate continuous functions that prove to constitute an orthonormal basis for the L$\sp2$ space. We also investigate the connection of this transform to the sampled wavelet series of nonorthogonal functions with good time-frequency localization properties. Finally, we see the way that the DWT maps a discrete signal in the phase plane and the applications that such representations incorporate.
Show less - Date Issued
- 1993
- PURL
- http://purl.flvc.org/fcla/dt/14944
- Subject Headings
- Wavelets (Mathematics), Integrals, Singular, Signal processing--Digital techniques
- Format
- Document (PDF)
- Title
- Voice activity detection over multiresolution subspaces.
- Creator
- Schultz, Robert Carl., Florida Atlantic University, Erdol, Nurgun, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Society's increased demand for communications requires searching for techniques that preserve bandwidth. It has been observed that much of the time spent during telephone communications is actually idle time with no voice activity present. Detecting these idle periods and preventing transmission during these idle periods can aid in reducing bandwidth requirements during high traffic periods. While techniques exist to perform this detection, certain types of noise can prove difficult at best...
Show moreSociety's increased demand for communications requires searching for techniques that preserve bandwidth. It has been observed that much of the time spent during telephone communications is actually idle time with no voice activity present. Detecting these idle periods and preventing transmission during these idle periods can aid in reducing bandwidth requirements during high traffic periods. While techniques exist to perform this detection, certain types of noise can prove difficult at best for signal detection. The use of wavelets with multi-resolution subspaces can aid detection by providing noise whitening and signal matching. This thesis explores its use and proposes a technique for detection.
Show less - Date Issued
- 1999
- PURL
- http://purl.flvc.org/fcla/dt/15740
- Subject Headings
- Speech processing systems, Signal processing--Digital techniques, Wavelets (Mathematics)
- Format
- Document (PDF)
- Title
- Synchronous spatial array processing for underwater vehicle tracking.
- Creator
- Normand, Olivier., Florida Atlantic University, Schock, Steven G., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
Navigation of Unmanned Underwater Vehicles (UUVs) is commonly assisted in confined areas by acoustic positioning systems. The Department of Ocean Engineenng at Florida Atlantic University is developing an altemative system based on submerged modems. This thesis describes an optimal target location estimation technique using a multi-channel spatial receiver array (Millscross) used as a development tool combined with a synchronous modem and transponder network mounted on buoys and UUVs. The...
Show moreNavigation of Unmanned Underwater Vehicles (UUVs) is commonly assisted in confined areas by acoustic positioning systems. The Department of Ocean Engineenng at Florida Atlantic University is developing an altemative system based on submerged modems. This thesis describes an optimal target location estimation technique using a multi-channel spatial receiver array (Millscross) used as a development tool combined with a synchronous modem and transponder network mounted on buoys and UUVs. The Millscross provides a reference to evaluate the performance of the navigation estimator. Spatial array principles are used to develop decoding and beamforming techniques to process modem messages, enabling the end user (the UUV) to estimate in real-time its own position and navigate in space. A simulation was used to compare actual results with theory and determine the processing and decoding algorithms. These algorithms were then applied to real data to estimate the target position (direction of arrival and geodetic coordinates).
Show less - Date Issued
- 2002
- PURL
- http://purl.flvc.org/fcla/dt/12917
- Subject Headings
- Underwater navigation, Underwater acoustics, Signal processing--Digital techniques
- Format
- Document (PDF)
- Title
- Concurrent linear predictive coding.
- Creator
- McLean, William Gregory., Florida Atlantic University, Erdol, Nurgun, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
This thesis describes a software model of a Linear Predictive Coding (L.P.C.) that is written in the Ada language. The novel feature of this program is that it attempts to execute the maximum possible number of concurrent arithmetic operations in the L.P.C. algorithm. Each arithmetic operation is implemented by an active process which is the "task" construct in the Ada language. The computational part of the algorithm is implemented as a wavefront array of computing tasks. These computational...
Show moreThis thesis describes a software model of a Linear Predictive Coding (L.P.C.) that is written in the Ada language. The novel feature of this program is that it attempts to execute the maximum possible number of concurrent arithmetic operations in the L.P.C. algorithm. Each arithmetic operation is implemented by an active process which is the "task" construct in the Ada language. The computational part of the algorithm is implemented as a wavefront array of computing tasks. These computational arrays are driven by a driver task which coordinates the flow of data into and out of the computing surfaces. If the inter process communications time between tasks is small, then this model shows a potential for speed-up. If this be the case, one may conclude that this model is an appropriate implementation for a linear predictive coding.
Show less - Date Issued
- 1989
- PURL
- http://purl.flvc.org/fcla/dt/14498
- Subject Headings
- Signal processing--Digital techniques, Signal processing, Programming languages (Electronic computers)
- Format
- Document (PDF)
- Title
- Estimation of the scattering function of fading channels for acoustic communications in shallow waters.
- Creator
- Allemand, Vincent., Florida Atlantic University, Beaujean, Pierre-Philippe
- Abstract/Description
-
The measurement of the Scattering function of time-variant fading channels is of strong interest in the field of underwater acoustic communications, as it indicates the limitations of the channel capacity. It also helps reducing the development time of acoustic communication systems and the need for on-site tests using so-called "fading simulators". The Scattering function is interpreted as the expected power received at a given time-delay and frequency shift for a given signal transmitted...
Show moreThe measurement of the Scattering function of time-variant fading channels is of strong interest in the field of underwater acoustic communications, as it indicates the limitations of the channel capacity. It also helps reducing the development time of acoustic communication systems and the need for on-site tests using so-called "fading simulators". The Scattering function is interpreted as the expected power received at a given time-delay and frequency shift for a given signal transmitted through the acoustic channel. It has been estimated using a fourth-moment method developed by Kailath from 18 to 30 kHz, 8-ms broad-band chirps and 20--28 kHz, 28-ms pseudo noise sequences. These signals were transmitted periodically in the shallow coastal waters of South Florida from a static source, and recorded from a 64-channel receiver array located at a distance of 1000 meters. Spatial beamforming has been applied to study the spatial sensitivity of the scattering function.
Show less - Date Issued
- 2005
- PURL
- http://purl.flvc.org/fcla/dt/13230
- Subject Headings
- Underwater acoustic telemetry, Signal processing--Digital techniques, Underwater acoustics--Mathematical models, Adaptive signal processing
- Format
- Document (PDF)
- Title
- Acoustic impulse response mapping for acoustic communications in shallow water.
- Creator
- Caimi, F. M., Tongta, R., Harbor Branch Oceanographic Institute
- Date Issued
- 1998
- PURL
- http://purl.flvc.org/FCLA/DT/3183706
- Subject Headings
- Electro-acoustics, Sound --Measurement, Acoustical engineering, Digital communications, Signal processing, Signals and signaling, Underwater acoustics, Signal processing --Digital techniques
- Format
- Document (PDF)
- Title
- A software-hardware implementation of a real-time digital signal processing receiver for noise detection using a broadband microwave correlation technique.
- Creator
- Christodoulou, Christodoulos A., Florida Atlantic University, Helmken, Henry
- Abstract/Description
-
In this research project the objective is to realize a software - hardware design implementation of a real time digital signal processing (DSP) radiometer - receiver for atmospheric noise temperature detection using the digital cross correlation technique. Atmospheric noise in the band of 20-30 GHz band is down-converted to 10.7 MHz IF and 3 MHz bandwidth in the form of statistical additive white gaussian noise which is used as the received signal by a digital signal processing broadband...
Show moreIn this research project the objective is to realize a software - hardware design implementation of a real time digital signal processing (DSP) radiometer - receiver for atmospheric noise temperature detection using the digital cross correlation technique. Atmospheric noise in the band of 20-30 GHz band is down-converted to 10.7 MHz IF and 3 MHz bandwidth in the form of statistical additive white gaussian noise which is used as the received signal by a digital signal processing broadband microwave radiometer based on the digital cross correlation technique. Living in a technological era, which is characterized as the era of data transmission and reception for RF-wireless communication systems, the theory of RF digital signal processing detection has applied to radar, ultrasound, and digital communications. Due to the need of high speed of data detection, much effort has gone into the design and development of sophisticated equipment to obtain such DSP detectors. Detection can also apply in seismic and big earthquake measurements by using geophones, nuclear testing, sonar and acoustic localizations, and even for oil excavations. Based on a statistical model and proposed design implementation, a basic DSP atmospheric noise temperature radiometer system is introduced and developed. The realization of the DSP Radiometer examines the noise characteristics (parameters) and their corresponding parameter values at the received input at the Antenna. It is essential to introduce the fundamental and statistical properties of the additive white gaussian noise, as well as the key-parameters which are used for the development of this real time design implementation. A design implementation of the proposed DSP atmospheric noise radiometer is discussed and developed via a statistical analysis. The statistical analysis utilizes the standard deviation, intermediate frequency, bandwidth, number of samples, and the temperature of the noise received signal at the antenna. Measurements and real time simulations in order to evaluate the noise temperature’s detectability in terms of system’s accuracy and performance of the noise random variable are also presented in this research work. The advantage of the digital cross correlation technique is examined and investigated.
Show less - Date Issued
- 2005
- PURL
- http://purl.flvc.org/fcla/dt/13290
- Subject Headings
- Signal processing--Digital techniques, Analog-to-digital converters, Radio--Receivers and reception
- Format
- Document (PDF)
- Title
- DSP implementation of turbo decoder using the Modified-Log-MAP algorithm.
- Creator
- Khan, Zeeshan Haneef., Florida Atlantic University, Zhuang, Hanqi, Sudhakar, Raghavan, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
The design of any communication receiver needs to addresses the issues of operating under the lowest possible signal-to-noise ratio. Among various algorithms that facilitate this objective are those used for iterative decoding of two-dimensional systematic convolutional codes in applications such as spread spectrum communications and Code Division Multiple Access (CDMA) detection. A main theme of any decoding schemes is to approach the Shannon limit in signal-to-noise ratio. All these...
Show moreThe design of any communication receiver needs to addresses the issues of operating under the lowest possible signal-to-noise ratio. Among various algorithms that facilitate this objective are those used for iterative decoding of two-dimensional systematic convolutional codes in applications such as spread spectrum communications and Code Division Multiple Access (CDMA) detection. A main theme of any decoding schemes is to approach the Shannon limit in signal-to-noise ratio. All these decoding algorithms have various complexity levels and processing delay issues. Hence, the optimality depends on how they are used in the system. The technique used in various decoding algorithms is termed as iterative decoding. Iterative decoding was first developed as a practical means for decoding turbo codes. With the Log-Likelihood algebra, it is shown that a decoder can be developed that accepts soft inputs as a priori information and delivers soft outputs consisting of channel information, a posteriori information and extrinsic information to subsequent stages of iteration. Different algorithms such as Soft Output Viterbi Algorithm (SOVA), Maximum A Posteriori (MAP), and Log-MAP are compared and their complexities are analyzed in this thesis. A turbo decoder is implemented on the Digital Signal Processing (DSP) chip, TMS320C30 by Texas Instruments using a Modified-Log-MAP algorithm. For the Modified-Log-MAP-Algorithm, the optimal choice of the lookup table (LUT) is analyzed by experimenting with different LUT approximations. A low complexity decoder is proposed for a (7,5) code and implemented in the DSP chip. Performance of the decoder is verified under the Additive Wide Gaussian Noise (AWGN) environment. Hardware issues such as memory requirements and processing time are addressed for the chosen decoding scheme. Test results of the bit error rate (BER) performance are presented for a fixed number of frames and iterations.
Show less - Date Issued
- 2002
- PURL
- http://purl.flvc.org/fcla/dt/12948
- Subject Headings
- Error-correcting codes (Information theory), Signal processing--Digital techniques, Coding theory, Digital communications
- Format
- Document (PDF)
- Title
- Digital signal processing for a high-resolution three-dimensional sonar imaging system for autonomous underwater vehicles.
- Creator
- Cao, Ping., Florida Atlantic University, Cuschieri, Joseph M., Sudhakar, Raghavan, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
In this dissertation, the digital signal processing techniques required for a 3-D sonar imaging system are examined. The achievable performance of the generated images is investigated by using a combination of theoretical analysis, computer simulation and field experiments. The system consists of a forward looking sonar, with separate projector and receiver. The projector is a line source with an 80 degrees by 1.2 degree beam pattern, which is electronically scanned within a 150 degree sector...
Show moreIn this dissertation, the digital signal processing techniques required for a 3-D sonar imaging system are examined. The achievable performance of the generated images is investigated by using a combination of theoretical analysis, computer simulation and field experiments. The system consists of a forward looking sonar, with separate projector and receiver. The projector is a line source with an 80 degrees by 1.2 degree beam pattern, which is electronically scanned within a 150 degree sector. The receiver is a multi element line array, where each transducer element has a directivity pattern that covers the full sector of view, that is 150 degrees by 80 degrees. The purpose of this sonar system is to produce three dimensional (3-D) images which display the underwater topography within the sector of view up to a range of 200 meters. The principle of operation of the proposed 3-D imaging system differs from other commonly used systems in that it is not based on the intensity of backscatter. The geometries of the targets are obtained from the delay and direction information that can be extracted from the signal backscatter. The acquired data is further processed using an approach based on sequential Fourier transforms to build the 3-D images. With careful selection of the system parameters, the generated images have sufficient quality to be used for AUV tasks such as obstacle avoidance, navigation and object classification. An approach based on a sophisticated two dimensional (2-D) autoregressive (AR) model is explored to further improve the resolution and generate images with higher quality. The real time processing requirements for image generation are evaluated, with the use of dedicated Digital Signal Processing (DSP) chips. A pipeline processing model is analyzed and developed on a selected system.
Show less - Date Issued
- 1992
- PURL
- http://purl.flvc.org/fcla/dt/12317
- Subject Headings
- Sonar, Signal processing--Digital techniques, Three-dimensional display systems, Submersibles
- Format
- Document (PDF)
- Title
- Feasibility of target tracking for high speed high seas cargo transfer.
- Creator
- Tucker, Glenn C., Florida Atlantic University, Driscoll, Frederick R., College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
At sea cargo transfer has historically been a logistical challenge for both the military and the offshore industry. Even in moderate seas, three to five foot wave heights, extreme pendulations of cargo and large relative motions between vessels can occur that halts cargo transfer activities. This work develops a six-degree-of-freedom rigid crane dynamics model that is used to investigate the feasibility of crane target tracking which could extend and enhance offshore crane operations. A...
Show moreAt sea cargo transfer has historically been a logistical challenge for both the military and the offshore industry. Even in moderate seas, three to five foot wave heights, extreme pendulations of cargo and large relative motions between vessels can occur that halts cargo transfer activities. This work develops a six-degree-of-freedom rigid crane dynamics model that is used to investigate the feasibility of crane target tracking which could extend and enhance offshore crane operations. A double girder crane system is developed that easily adapts to different configurations and efficiently supports long reach heavy lift applications. Target tracking is feasible in sea states up to 5 when using the double girder crane. When compared to a present crane system, the target tracking crane requires, on average, only 3.65% more absolute total system power and 13.4% less continuous power, indicating that the proposed system should be realizable.
Show less - Date Issued
- 2006
- PURL
- http://purl.flvc.org/fcla/dt/13388
- Subject Headings
- Cargo handling, Unitized cargo systems, Signal processing--Digital techniques, Ocean circulation--Mathematical models
- Format
- Document (PDF)
- Title
- Identification and approximation of one-dimensional and two-dimensional digital filters.
- Creator
- Wang, Dali., Florida Atlantic University, Zilouchian, Ali, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
In this dissertation, identification and approximation of one-dimensional (1-D) and two-dimensional (2-D) recursive digital filters are addressed. In the identification phase, a novel Neural Network (NN) structure is proposed which provides the state-space model of 1-D filters based upon input-output data. The state space identification technique is also extended to 2-D digital filters and several comparison studies are performed. In the approximation phase, frequency-domain balanced...
Show moreIn this dissertation, identification and approximation of one-dimensional (1-D) and two-dimensional (2-D) recursive digital filters are addressed. In the identification phase, a novel Neural Network (NN) structure is proposed which provides the state-space model of 1-D filters based upon input-output data. The state space identification technique is also extended to 2-D digital filters and several comparison studies are performed. In the approximation phase, frequency-domain balanced structures for 1-D as well as 2-D digital filters are proposed. The model reduction technique is based on the conceptual view point of balancing the controllability and observability Grammians of a digital filter in an arbitrary frequency range of operation. Finally, the interrelations between these two phases are presented. Extensive simulation experiments are presented to demonstrate the effectiveness of proposed methods.
Show less - Date Issued
- 1998
- PURL
- http://purl.flvc.org/fcla/dt/12555
- Subject Headings
- Digital filters (Mathematics), Signal processing--Digital technique, Electric filters, Digital
- Format
- Document (PDF)
- Title
- The Comprehensive Evaluation of Performance and Environmental Influence on MPSK Modulated High-Speed Acoustic Communications in Shallow Water.
- Creator
- Proteau, Joshua C., Beaujean, Pierre-Philippe, Florida Atlantic University, College of Engineering and Computer Science, Department of Ocean and Mechanical Engineering
- Abstract/Description
-
A daily study spanning a month of the shallow water acoustic channel was conducted to estimate the environmental influence on performance of an underwater acoustic communications system. An automated acoustic modem transmitted phase-coherent modulated sequences of identical data with 186 dB re IpPa source level, at coded rates from 4000 to 16000 bits/s with 4 or 8 kHz symbol bandwidth, three times daily for a month. A 64 channel Mills-Cross receiver array was used with horizontal and vertical...
Show moreA daily study spanning a month of the shallow water acoustic channel was conducted to estimate the environmental influence on performance of an underwater acoustic communications system. An automated acoustic modem transmitted phase-coherent modulated sequences of identical data with 186 dB re IpPa source level, at coded rates from 4000 to 16000 bits/s with 4 or 8 kHz symbol bandwidth, three times daily for a month. A 64 channel Mills-Cross receiver array was used with horizontal and vertical beams each containing 32 and 33 elements respectively, spaced 0.03 meters apart, with a sampling frequency of 72 kHz. Source and receiver were deployed at depths of 20 meters respectively, with a 720 meter separation range. Environmental measurements of wind velocity and direction, surface wave activity, current and sound velocity profiles, and tidal measurements were performed. Results demonstrate reliable achievement of high data-rate shallow water acoustic communications using phase-coherent modulation techniques.
Show less - Date Issued
- 2006
- PURL
- http://purl.flvc.org/fau/fd/FA00012541
- Subject Headings
- Underwater acoustics--Measurement, Artificial satellites in telecommunication, Underwater acoustic telemetry, Signal processing--Digital techniques
- Format
- Document (PDF)
- Title
- Matched filter bound for frequency-selective Nakagami fading channel.
- Creator
- Jiao, Jiemei., Florida Atlantic University, Aalo, Valentine A.
- Abstract/Description
-
Based on the theoretical method developed by Clark and Greenstein for frequency-selective Rayleigh fading channel, we develop a general model for frequency-selective Nakagami fading channel. We derive analytical expressions of the average bit-error-rate in an ideal space diversity mobile radio receiver using the matched filter bound. Our simulation results show that the influences of the diversity order, the shape of the multipath delay profile, and delay spread of the multipath delay profile...
Show moreBased on the theoretical method developed by Clark and Greenstein for frequency-selective Rayleigh fading channel, we develop a general model for frequency-selective Nakagami fading channel. We derive analytical expressions of the average bit-error-rate in an ideal space diversity mobile radio receiver using the matched filter bound. Our simulation results show that the influences of the diversity order, the shape of the multipath delay profile, and delay spread of the multipath delay profile. Five shapes are considered in our simulation. Our simulation results highlight the importance of the ratio the normalized delay spread d. The results show that the delay profile is of no importance for $d<0.3,$ but can have a profound influence for $d\geq0.3.$
Show less - Date Issued
- 1995
- PURL
- http://purl.flvc.org/fcla/dt/15223
- Subject Headings
- Digital communications, Signal processing--Digital techniques, Radio--Transmitters and transmission--Fading
- Format
- Document (PDF)
- Title
- Interactive graphical tools for digital signal processing education.
- Creator
- Aksaray, Ali Ercument., Florida Atlantic University, Erdol, Nurgun
- Abstract/Description
-
In this thesis, we develop a set of programs in the MATLAB RTM Graphical User Interface environment, for use as an Interactive Digital Signal Processing Laboratory. The software toolbox consists of programs on selected topics covered in undergraduate Digital Signal Processing courses. Care is taken to give the user sufficient degrees of freedom to illustrate the effect of various parameter changes. Program code is left open and well documented to allow expansion.
- Date Issued
- 2002
- PURL
- http://purl.flvc.org/fcla/dt/12960
- Subject Headings
- Signal processing--Digital techniques--Study and teaching, Multimedia systems, Graphical user interfaces (Computer systems)
- Format
- Document (PDF)
- Title
- Integrating Multi-user Scheduling with Retransmission Diversity over Wireless Links.
- Creator
- Li, Irena, Zhuang, Hanqi, Wang, Xin, Florida Atlantic University, College of Engineering and Computer Science, Department of Computer and Electrical Engineering and Computer Science
- Abstract/Description
-
Research presented in this thesis develops a mainly theoretical basis and computer models for enhancing the throughput of multi-user wireless communication networks. The cross-layer combination of an adaptive modulation and coding (AMC) scheme at the physical layer and the use of automatic repeat request (ARQ) retransmi ssions at the data link layer is integrated into a scheduling framework for multi-user networks. Scheduling algorithms incorporating retransmission diversity are derived for...
Show moreResearch presented in this thesis develops a mainly theoretical basis and computer models for enhancing the throughput of multi-user wireless communication networks. The cross-layer combination of an adaptive modulation and coding (AMC) scheme at the physical layer and the use of automatic repeat request (ARQ) retransmi ssions at the data link layer is integrated into a scheduling framework for multi-user networks. Scheduling algorithms incorporating retransmission diversity are derived for three cases of typical network traffic: best-effort, non-realtime, and realtime. For each case, numeric computer si mulations of wireless communications over Nakagami-m block fading channels are developed to examine the effectiveness of the formulated schemes.
Show less - Date Issued
- 2008
- PURL
- http://purl.flvc.org/fau/fd/FA00012533
- Subject Headings
- Wireless communication networks, Code division multiple access, Modulation (Electronics), Signal processing (Digital techniques)
- Format
- Document (PDF)
