Organization:
Electrical and Computer Engineering (ECE)

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2022
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The mission of the Electrical and Computer Engineering department is to provide relevant and unique advanced education and research programs to meet Naval unique needs, and increase the warfighting effectiveness of the U.S. Naval Forces, DoD and allied armed forces. Our students include commissioned officers of the Naval Service, other U.S. and allied armed forces, civilian employees of the Defense Department and international defense establishments. Civilian employees of DoD contractors are also eligible to attend NPS in limited numbers.
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Publication Search Results

Now showing 1 - 10 of 98
  • Publication
    Investigation of feature dimension reduction schemes for classification applications
    (Monterey, California. Naval Postgraduate School, 2001-06) Fargues, Monique P.; Electrical and Computer Engineering (ECE); Graduate School of Engineering and Applied Science (GSEAS); Center for Reconnaissance Research
    Extracting relevant features that allow for class discrimination is the first critical step in classification applications. However, this step often leads to high-dimensional feature spaces, which requires large datasets to create viable classification schemes. As a result, there is a strong incentive to reduce the feature space dimension. Two classical types of approaches to reduce feature dimension exist Principal Component Analysis (PCA)-based or discriminant-based approaches. The main difference between the two types lies in the criterion selected; PCA-based schemes seek a projection direction which bests represents the data in a norm sense, while discriminant-based schemes seek a projection that best separates the class data. This study presents a comparison of three discriminant-based feature dimension reduction schemes: the Mean Separator Neural Network (MSNN), the Mahalanobis-based Dimension Reduction scheme (MBDR), and the kernel-based Generalized Discriminant Analysis (GDA) approach. PCA is included for comparison purposes as it is also widely used in classification applications. All four feature dimension reduction schemes are implemented and evaluated by applying the transformed features to a basic minimum distance classifier. Three classification datasets commonly used in statistics for benchmarking purposes are selected to compare the schemes and results discussed Results show the kernel-based generalized discriminant analysis approach to lead to consistently higher classification performances than the other schemes considered in the study for the data investigated.
  • Publication
    Analyzing VLSI component test results of a GenRad GR125 tester
    (Monterey, California. Naval Postgraduate School, 1995-06) Zulaica, Dan; Lee, Chin-Hwa; Electrical and Computer Engineering (ECE); Graduate School of Engineering and Applied Science (GSEAS); Electrical and Computer Engineering
  • Publication
    A hierarchical approach to the classification of digital modulation types in multipath environments
    (Monterey, California. Naval Postgraduate School, 2001-05) Fargues, Monique P.; Hatzichristos, G.; Electrical and Computer Engineering (ECE); Graduate School of Engineering and Applied Science (GSEAS); Electrical and Computer Engineering
    This study presents a hierarchical classification approach to the classification of digital modulation schemes of types 2,4,8-PSK, 2,4,8-FSK and 16,64,256-QAM in low SNR levels and multipath propagation channel conditions. A hierarchical tree-based classification approach is selected as it leads to a relatively simple overall scheme with few parameters needed to differentiate between the various modulation types. Back-propagation neural network units are adopted at each tree node because they offer the flexibility needed to cope with varying propagation environments, as is the case in real-world communications. The selection of robust and well-defined higher-order statistics-based class features is considered and a small number of cumulates and moments chosen to differentiate between all various types of modulation types, except for specific M-QAM types. Simulations show that M-QAM types may be so affected by multipath and fading that higher-order statistic parameters become of very limited use. While being part of the hierarchical procedure, the identification of specific M-QAM types is conducted via equalization algorithms. Extensive simulations show overall classification performances to be strongly affected by the amount of multipath distortion and noise in the transmission channels. Results also show a much higher sensitivity of high-order M-QAM types to fading and multipath propagation distortions than other modulation types.
  • Publication
    Step frequency high PRF waveform design
    (Monterey, California. Naval Postgraduate School, 1996-06) Gill, Gurnam Singh, 1940-; Soares, Paulo A.; Electrical and Computer Engineering (ECE); Graduate School of Engineering and Applied Science (GSEAS); Research and Sponsored Programs Office (RSPO); Electrical and Computer Engineering
  • Publication
    Analysis Using Bi-spectral Related Technique
    (Monterey, California. Naval Postgraduate School, 1993-11) Hippenstiel, Ralph Dieter; Electrical and Computer Engineering (ECE); Graduate School of Engineering and Applied Science (GSEAS); Electrical and Computer Engineering
    This report investigates the use of Bi-spectral related techniques to extract detection/classification clues from time frequency representations. Earlier results have indicated that 1.5-D spectral techniques (a degenerate version of the Bi-spectrum) has potential Signal to Noise Ratio (SNR) gain over conventional techniques. This is partially due to the rejection of Gaussian like perturbations by the cumulant based techniques. The third order moment for Gaussian zero mean random processes is essentially zero. It is assumed that (1) the independence of the Instantaneous Power Spectrum (IPS) from analytic signal representations and (2) the Gaussian character of the noise causes minimal distortion of the output vaxiables, hence permit signal characterization at low to moderate SNRs. The per rm ce is demonstrated on (1) synthetic signals and (2) on segment(s) of the NOSC data set.
  • Publication
    Classification of Ocean Acoustic Data Using AR Modeling and Wavelet Transforms
    (Monterey, California. Naval Postgraduate School, 1997-01) Fargues, Monique P.; Bennett, R.; Barsanti, R.J.; Electrical and Computer Engineering (ECE); Graduate School of Engineering and Applied Science (GSEAS); Electrical and Computer Engineering
    This study investigates the application of orthogonal, non-orthogonal wavelet-based procedures, and AR modeling as feature extraction techniques to classify several classes of underwater signals consisting of sperm whale, killer whale, gray whale, pilot whale, humpback whale, and underwater earthquake data. A two-hidden-layer back-propagation neural network is used for the classification procedure. Performance obtained using the two wavelet-based schemes are compared with those obtained using reduced-rank AR modeling tools. Results show that the non-orthogonal undecimated A-trous implementation with multiple voices leads to the highest classification rate of 96.7%
  • Publication
    A Look Back at the History of the NPS and the Electrical Engineering Department
    (Monterey, California. Naval Postgraduate School, 2000-07-27) Sheingold, Abe; Electrical and Computer Engineering (ECE); Graduate School of Engineering and Applied Science (GSEAS); Electrical and Computer Engineering (ECE)
    A poster advertising a talk by Prof. Sheingold on the topic of how the ECE department evolved from the 1940s to the 1970s, and to provide a background on origins of the ECE department and on how portions of the Physics, Electronics and the traditional Electrical Engineering (machinery) evolved into the organization of that time; the exodus from Annapolis; a review of the past chairmen and how the campus changed. Prof. Emeritus Conley Smith provided videos and images of NPS both in Monterey and in Annapolis to accompany the talk.
  • Publication
    Detection and parameter estimation of chirped radar signals
    (Monterey, California. Naval Postgraduate School, 2000-01-10) Hippenstiel, Ralph Dieter; Fargues, Monique P.; Moraitakis, I.; Williams, C.; Electrical and Computer Engineering (ECE); Graduate School of Engineering and Applied Science (GSEAS); Electrical and Computer Engineering
    This work investigated the detection of pulses and extraction of modulation parameters from different types of time-limited chirp signals, as may be found in pulse- compression radar signals. The work is split into two parts. The first part examines the pulse detection problem, i.e., the detection of the pulse start/stop times. Such information can be used to determine the pulse width and repetition rate of the radar systems under investigation in an automated fashion. We compare the robustness of three TCF-based schemes and an envelope detection algorithm in noisy environments.
  • Publication
    Integrated masts for ship radiofrequency electromagnetic interference mitigation – a preliminary electromagnetic characterization study (u)
    (Monterey, California. Naval Postgraduate School, 2011-12) Dall’Armi-Stoks, Giuseppina; Electrical and Computer Engineering (ECE); Graduate School of Engineering and Applied Science (GSEAS); Engineer and Scientist Exchange Program (ESEP)
    This report provides an electromagnetic characterization analysis in order to ascertain if integrated masts are an effective ship radiofrequency electromagnetic interference mitigation strategy. Free space and fitted antenna radiation patterns, and fitted relative near field power flux densities of a linear array transmitting antenna, and the mutual antenna-to-antenna coupling between a linear array transmit and receive antennas, both fitted on the same mast structure, was determined. Overall, the mast structure can reduce the mutual antenna-to-antenna coupling (up to ~20dB) and can affect the fitted antenna radiation pattern. There is both significantly high (i.e., up to 0 dB) and low (~ -30dB) fitted relative near field power flux density within the vicinity of the transmitting antenna and regions around the mast structure. All this depends on the location and position of the transmit antenna relative to the mast structure, and the location of the receiver antenna relative to the transmit antenna. Both desensitization and third order subharmonic distortions non-linear effects on the receiver antenna system were also assessed due to the fitted relative near field power densities. Depending on the specifications of the receiver system, desensitization (or gain compression) was found to be significant, whereas, third order sub-harmonic distortion was not..
  • Publication
    Symmetrical number system phase sampled interferometer direction finding antennas
    (Monterey, California. Naval Postgraduate School, 1998-02) Jenn, David C.; Pace, Phillip E.; Electrical and Computer Engineering (ECE); Graduate School of Engineering and Applied Science (GSEAS); Dept. of Electrical and Computer Engineering.