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Актуальність теми: пов’язана із необхідністю підвищення швидкості оперативного контролю та управління процесами передачі даних за рахунок розроблення способів класифікації інформаційних сигналів на основі застосування методу оптимального дерева рішень. Мета та завдання дослідження: Метою роботи є підвищення швидкодії та надійності системи передачі даних. Для чого потрібно розробити спосіб більш точного і швидкого аналізу та обробки інформаційних сигналів. Для досягнення поставленої мети необхідно вирішити низку завдань: 1. Проаналізувати сучасні методи класифікації інформаційних сигналів, їх основні способи опису, аналізу та обробки сигналів. 2. Дослідити аспекти використання методу дерева рішень, його алгоритми та етапи побудови. 3. Розробити метод класифікації інформаційних сигналів шляхом побудови оптимального дерева рішень. 4. Привести способи практичного застосування розробленого методу та проаналізовати його ефективність. Об’єктом дослідження: процеси аналізу та обробки інформаційних сигналів, метод дерева рішень та його особливості. Предмет дослідження: існуючі методи класифікації та аналізу інформаційних сигналів. Основні принципи їх обробки. Процес побудови оптимального дерева рішень. Методи дослідження: Розробки і дослідження проводилися на основі теорії аналізу інформаційних сигналів, теорії перетворень Лапласа, теорії перетворень Котельнікова, теорії рядів Фур’є, теорії вейвлет-аналізу, теорії метода дерева рішень. Наукова новизна одержаних результатів: 1. Проведено порівняльну характеристику методів опису, аналізу та обробки сигналів. 2. Досліджено сучасні способи ідентифікації та класифікації інформаційних сигналів. 3. Створено спосіб класифікації інформаційних сигналів на основі метода оптимального дерева рішень. Практичне значення одержаних результатів: Отримані в роботі наукові результати мають практичне значення для покращення процесів передачі даних, що дозволить вдосконалити методи швидкісної передачі інформації в мережах, що використовуються в к, Relevance of the topic: related to the need to increase the speed of operational control and management of data transmission processes through the devel-opment of methods for classifying information signals based on the application of the optimal decision tree method. Aim and objectives of the study: The aim of the work is to increase the speed and reliability of the data transmission system. For what it is necessary to develop a way of more exact and fast analysis and processing of information signals. To achieve this goal it is necessary to solve a number of tasks: 1. Analyze modern methods of classification of information signals, their main methods of description, analysis and signal processing. 2. Investigate aspects of using the decision tree method, its algorithms and construction stages. 3. Develop a method for classifying information signals by constructing an optimal decision tree. 4. Give ways of practical application of the developed method and analyze its effectiveness. Object of research: processes of analysis and processing of information signals, method of decision tree and its features. Subject of research: existing methods of classification and analysis of information signals. Basic principles of their processing. The process of building an optimal decision tree. Research methods: Developments and researches were carried out on the basis of the theory of the analysis of information signals, the theory of transformations of Laplace, the theory of transformations of Kotelnikov, the theory of Fourier series, the theory of wavelet analysis, the theory of a method of a tree of decisions. Scientific novelty of the obtained results. 1. A comparative description of the methods of description, analysis and signal processing. 2. Modern methods of identification and classification of information sig-nals are investigated. 3. A method of classification of information signals based on the method of optimal decision tree is created. The practical significance of

We present the results of the development of high-density 3-D interconnect technology that is applicable to the integration of heterogeneous integrated circuits. The technology relies on through-silicon vias, advanced thinning of silicon wafers, and copper/tin-copper solid-liquid diffusion bonding to produce vertical interconnects at a density of 1 x 10(exp 6)/sq cm. The processing approach allows for the integration of known-good-die in either die-to-die or die-to-wafer bonding configurations, providing the flexibility desirable for the implementation in mixed-signal microsystems., See also ADB387878. Presented at the GOMACTech-13 Government Microcircuit Applications and Critical Technology Conference (38th) on Microelectronics for Net-Enabled and Cyber Transformational Technologies held in Las Vegas, Nevada, on 11-14 March 2013, p641-644.

Photonic systems that transmit and process microwave-frequency analog signals have traditionally been encumbered by relatively large signal distortion and noise. Optical phase modulation (PM) and frequency modulation (FM) are promising techniques that can improve system performance. In this dissertation, I discuss an optical filtering approach to demodulation of PM and FM signals, which does not rely on high frequency electronics, and which scales in linearity with increasing photonic integration. I present an analytical model, lter designs and simulations, and experimental results using planar lightwave circuit (PLC) lters and FM distributed Bragg re ec- tor (DBR) lasers. The linearity of the PM and FM photonic links exceed that of the current state-of-the-art.

A narrow-band photonic sigma-delta digital antenna is described as a system intended to provide a proof of concept for the use of photonics technology in the sampling of wide-band radio frequency (RF) signals. The ability to sample wide-band RF signals is an important requirement in modern electronic warfare (EW) systems where a determination of the existence of complex and often difficult to detect signals is sought. As an example, the class of signals referred to as low probability of intercept (LPI) is becoming increasingly common-place with the evolution of modern radar and communication systems. The emergence of this class has led to a concomitant demand for receivers that can provide the necessarily high sensitivity to detect these signals thereby enabling their classification in an electronic intelligence (ELINT) database or jamming using electronic attack (EA). The described system is designed to oversample the analog RF signal exciting an antenna at a rate at least 10 times higher than the Nyquist rate relative to the RF signal frequency (that is, twice the RF signal frequency). Numerous aspects of the development of the described concept demonstrator are presented and extended to outline the requirements for progressing the technology to wide-band capability., The original document contains color images.

A signal processing system and method includes a transducer for receiving an analog signal having a random component and possibly an information component. The analog signal is converted into a digital signal having sample points. A nearest-neighbor calculation component calculates the expected average nearest neighbor distance between the sample points, the actual average distance and an error value. These values are corrected for edge effects. A first randomness assessment compares the actual average distance against the expected average distance with the standard error value. A second randomness assessment compares actual repeated values in the digital signal against expected repeated values. An information processing system continues processing the signal if the assessments indicate the possibility of an information component.

In this project, we focused on the architectural and circuit-level design for a low cost, portable soldier radio with high survivability. We identified passive switched capacitor circuits as a suitable candidate for meeting these performance targets. We developed an architecture that uses a high dynamic range FFT to perform low amplitude signal detection in the presence of large jammers. Based on our analysis and modeling of non-idealities in switched capacitors, we were able to construct and simulate a sampled charge based 16 point FFT processor. The processor is able to compute the FFT of a 2GHz wideband input signal using only 1mW total power with a dynamic range exceeding 65dB without noise averaging and 90dB with noise averaging. This performance exceeds the requirements for signal detection in a typical wireless war theater communications scenario., The original document contains color images.

We describe recent work with Sanjeev Khanna (U.\ Penn.) where we explore potential axioms about the mechanics of information transmission with a view to understanding whether continuous signals can carry more information than analog signals.

Analog-To-Digital Converters (ADCs) are integral building blocks of most sensor and communication systems today. As the need for ADCs with faster conversion speeds and lower power dissipation increases, there is a growing motivation to reduce the number of power-consuming components by employing folding circuits to fold the input analog signal symmetrically, prior to quantization by high-speed comparators. These properties of low-power consumption, compactness, high-resolution and fast conversion speeds make folding ADCs an attractive concept to be used for defense applications, such as unmanned systems, direction-finding antenna architectures and system-on-achip applications. In this thesis, a prototype of an optical folding ADC was implemented using the Robust Symmetrical Number System (RSNS). The architecture employs a three-modulus (Moduli 7, 8, 9) scheme to preprocess the antenna signal. This thesis focuses on the simulation and hardware implementation of this ADC architecture, including the bank of comparators and the RSNS-to-Binary Conversion within a Field Programmable Gate Array (FPGA), to achieve an eight-bit Dynamic Range of 133. This is then integrated with the front-end photonics implementation (designed under a separate thesis). Low frequency analyses of the results using a 1-kHz input signal indicate a 5.39 Effective Number of Bits (ENOB), a Signal-to-Noise Ratio plus Distortion (SINAD) of 34.21 dB, and a Total Harmonic Distortion (THD) of - 61.68 dB., The original document contains color images.

A method is provided for the design of a wide-band high dynamic-range electromagnetic signal receiving system. The method provides for receiving a plurality of analog signals, converting the plurality to a digital replica that can be processed to recover separate high-fidelity replicas of each individual signal in the received plurality. The method also provides increasing the signal dynamic range with a parallel architecture comprising p identical parallel analog-to-digital channels wherein the value of is determined by the ratio of the largest amplitude signal to the minimum detectable signal. Further, it is demonstrated that p is the fundamental limit on the number of parallel channels necessary to linearly process a specified plurality of signals containing a largest signal and a minimum detectable signal.

This thesis describes the design and development of an automated demodulator calibration station. Many commercial demodulator boards have an inherent problem of DC offset due to their direct down conversion architecture. It is necessary to measure the DC offset and compensate for it when the demodulator is used in a system such as a digital phase array. The proposed automated calibration station uses a combination of COTS hardware and software, such as NI PXI-1044 (PC) and LabVIEW programs, to digitally generate I and Q signals. The LabVIEW program cycles through phase shifts over a range of 00 to 3600. These signals are converted into analog outputs using NI PXI-6704 (DAC). Subsequently, these converted analog signals are fed into the modulator, going through an upconversion modulation process with an RF output. This RF output is adjusted to meet RFIN specification of the quadrature demodulator board before feeding into the board to recover the I and Q control signals, which are sampled by the NI PXI-5112 digitizer. After the full cycling of phase shifting by the modulator is completed, I and Q offsets are computed. This station has improvements over the existing manual calibration station, such as ease of use, shorter calibration time, accuracy and versatility for future modifications and improvements., The original document contains color images.

This thesis carried out the design and development of an integrated array and receiver processor that utilizes advanced techniques of Robust Symmetric Numeric System (RSNS) and monopulse Digital Beamforming (DBF) to accurately track a UAV using commercial-off-the-shelf (COTS) equipment. This was based on previous work done using virtual spacing RSNS and digital beamforming to extend the method to a functional six element array with direction finding and tracking capability. The six-element antenna array and direct-conversion receiver were developed and tested to retrieve a FM-modulated video signal encoded using the NTSC format. This thesis addresses system-level design tradeoffs, as well as hardware and software design, development and testing. A bench top test was conducted to test the functionality of the NTSC decoding and FM software modules developed and a comprehensive test was done in an anechoic chamber to characterize the array's capability in DF using RSNS and monopulse DBF., The original document contains color images.

Several novel phase-modulated fiber optic links for analog or microwave signal transport up to at least 20 GHz frequency are theoretically developed and experimentally demonstrated. Each link uses a linearization technique exploiting the Lithium Niobate modulator's electro-optic anisotropy between orthogonal crystallographic axes that has not previously been applied to phase-modulated links. This technique and its variants suppress the dominant third-order distortion product to extend the sub-octave spur-free dynamic range of the systems, and does so passively using the modulator instead of with processing at the receiver. Two of the links incorporate frequency downconversion, with one of them employing a new method to spectrally filter the local oscillator and signal sidebands together. This both downconverts the signal to an appropriate intermediate frequency and causes the phase modulation to appear as intensity modulation for photodetection with a low-speed detector. This technique does not require a separate optical oscillator source and can be implemented with commercial hardware., The original document contains color images. All DTIC reproductions will be in black and white.

The emerging theory of compressed sensing (CS) provides a universal signal detection approach for sparse signals at sub-Nyquist sampling rates. A small number of random projection measurements from the received analog signal would suffice to provide a salient information for signal detection. However, the compressive measurements are not efficient at gathering signal energy. In this paper, a set of detectors called subspace compressive detectors are proposed where a more efficient detection scheme can be constructed by exploiting the sparsity model of the underlying signal. Furthermore, we show that the signal sparsity model can be approximately estimated using reconstruction algorithms with very limited random measurements on the training signals. Based on the estimated signal sparsity model, an effective subspace random matrix can be designed for unknown signal detection, which significantly reduces the necessary number of measurements. The performance of the subspace compressive detectors is analyzed. Simulation results show the effectiveness of the proposed subspace compressive detectors., See also ADM002091. Presented at the IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP 2008), held in Las Vegas, Nevada on March 30-April 4, 2008. Published in the Proceedings of the IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP 2008) p3873-3876, 2008. The original document contains color images.

A parallel structure to do spectrum sensing in Cognitive Radio (CR) at sub-Nyquist rate is proposed. The structure is based on Compressed Sensing (CS) that exploits the sparsity of frequency utilization. Specifically, the received analog signal is segmented or time-windowed and CS is applied to each segment independently using an analog implementation of the inner product, then all the samples are processed together to reconstruct the signal. Applying the CS framework to the analog signal directly relaxes the requirements in wideband RF receiver front-ends. Moreover, the parallel structure provides a design flexibility and scalability on the sensing rate and system complexity. This paper also provides a joint reconstruction algorithm that optimally detects the information symbols from the sub-Nyquist analog projection coefficients. Simulations showing the efficiency of the proposed approach are also presented., See also ADM002091. Presented at the IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP 2008) held in Las Vegas, Nevada on 30 March - 4 April 2008. Published in the Proceedings of the IEEE International Conference on Acoustics, Speech, and Signal Processing (ICASSP 2008), p3861-3864, 2008. Government or Federal Purpose Rights License.

We report the implementation of an in-band chaotic scrambler for securing wireless analog video. In this demonstration system, an analog video signal is injected into a chaotic oscillator and the output is transmitted through a standard wireless video link. At the receiver, a descrambler separates the video from the chaotic signal in real time. Experimental results show the scrambled signal effectively hides the original video image, yet the descrambler recovers the original color video with reasonable clarity and detail. Compared to digital encryption, chaotic scrambling offers an efficient, lowcost alternative for masking time-critical analog communications., See also ADM002187. Presented at Proceedings of the Army Science Conference (26th) held in Orlando, FL on 1-4 December 2008. Published in Army Science Conference (26th) Proceedings, p1-7, December 2008. The original document contains color images.

Experimental results for a photonic recirculating delay line for high-speed, high-resolution Analog-to-Digital Converted (ADC) and other applications is presented. The approach modifies an analog fiber optic link with a recirculating optical loop as a means to store a time-limited microwave signal so that it may be digitized by using a slower, conventional electronic ADC. Detailed analytical analysis of the dynamic range and noise figure show that under appropriate conditions the microwave signal degradation is sufficiently small so as to allow the digitization of a multi-gigahertz signal with a resolution greater than 10 effective bits. Experimental results provided support the theory., Prepared in collaboration with the Department of Electrical and Computer Engineering, University of Florida, Gainesville, FL; Department of Electrical Engineering, State University of New York, Binghamton, NY; and the Department of Biomedical Engineering, Syracuse University, Syracuse, NY. Presented at the SPIE Defense + Security Conference, Orlando, FL on 16-20 Mar 2008. Published in Enabling Photonics Technologies for Defense, Security, and Aerospace Applications IV, Proceedings of the SPIE v6975 paper 69750F, 2008. The original document contains color images. The original document contains color images.

The direct-sequence spread-spectrum (DSSS) receiver performs demodulation of wideband DSSS signals, accepting as input an analogue signal at low intermediate frequency (IF) or baseband, and producing as output the recovered digital message bitstream. It consists of firmware (FW) entities that perform signal processing; a PCI-compliant digital processor card (DPC) that provides analogue to digital conversion and host resources for the FW; and a computer which hosts the DPC and runs software to access, control and monitor it. This manual provides the information required to allow an operator to connect, configure and dynamically control the DSSS Receiver in a precise way to achieve the best demodulation performance., The original document contains color images.

Networks have been rapidly evolving over the last several decades and continue to do so today. This evolution has been driven by a need for increased performance, as characterized by increased data rates and larger bandwidth. This project focused on the development of a reconfigurable network architecture that connects existing Local Area Networks (LANs) to create an extended LAN. The network uses optical fiber and supports data transparency. This Fully Interconnected Optical Network Architecture (FIONA), uses Dense Wavelength Division Multiplexing (DWDM), wavelength conversion and out-of-band control to achieve all-optical routing within the network. The architecture uses all-optical wavelength conversion as both a mechanism to route data and to reconfigure the network in the event of a link failure. A portion of the network was constructed and a simple control algorithm was implemented. Proof of concept testing was completed, demonstrating all-optical routing of data and out-of-band control. The network has demonstrated some ability to handle mixed signal transmission, and its data transparent nature allows for the connection of heterogeneous LANs to form a single extended LAN. The reconfigurability of the network improves survivability and fault tolerance without necessarily adding redundant systems or links. Fiber optics allow for higher data rates and larger available bandwidth compared to existing copper networks. The mixed signal nature of the network eliminates the need for pre-transmission conversion of analog data and enables the interconnection of analog and digital devices. FIONA is an improvement over existing access network architectures, such as those used in shipboard and avionics applications. It provides greater connectivity between local area networks, resulting in increased network performance., The original document contains color images.