The paper analyses and compares the possibility for airplanes detection by a FSR system that exploits radio emission from such cosmic bodies as Moon, Sun and pulsars. This possibility is estimated as a magnitude of SNR at the input of the... more
The paper analyses and compares the possibility for airplanes detection by a FSR system that exploits radio emission from such cosmic bodies as Moon, Sun and pulsars. This possibility is estimated as a magnitude of SNR at the input of the signal detector calculated depending on the frequency of reception, the size of airplanes, which are crossing the baseline of FSR at the approximately right angle and the distance from the receiver to airplanes.
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The presence of strong pulse jamming in a reference window used by Cell-Averaging CFAR detectors for noise power estimation can cause drastic degradation in performance even if the CA CFAR detectors employ binary integration. The... more
The presence of strong pulse jamming in a reference window used by Cell-Averaging CFAR detectors for noise power estimation can cause drastic degradation in performance even if the CA CFAR detectors employ binary integration. The technique for pulse jamming suppression discussed in this work is the use of filters matched to a broadband transmitted pulse in combination with an excision
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In the present paper, an algorithm for target detection that exploits the Hough transform is proposed. The target is detected by the Hough detector. The effectiveness of the algorithm proposed is formulated in terms of a quality parameter... more
In the present paper, an algorithm for target detection that exploits the Hough transform is proposed. The target is detected by the Hough detector. The effectiveness of the algorithm proposed is formulated in terms of a quality parameter - the probability of detection. The quality parameter is estimated using the Monte Carlo simulation approach. We compare the results of detection
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Track before detect (TBD) in netted radar system in the presence of multi false alarms is proposed and studied. The proposed structure uses TBD algorithm based on Polar Hough Transform (PHT). This algorithm improves the detection... more
Track before detect (TBD) in netted radar system in the presence of multi false alarms is proposed and studied. The proposed structure uses TBD algorithm based on Polar Hough Transform (PHT). This algorithm improves the detection probability of moving target along a straight line in conditions of multi false alarm. The advantage of the proposed approach is the data unification
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The aim of SSA is to make a decomposition of the original series (GPR traces in the considered case) into a sum of a small number of independent and interpretable components such as: low-frequency trends, narrowband quasi-periodic signals... more
The aim of SSA is to make a decomposition of the original series (GPR traces in the considered case) into a sum of a small number of independent and interpretable components such as: low-frequency trends, narrowband quasi-periodic signals and noise. In this paper SSA based algorithms that ldquocleanrdquo noise from the radargram and/or enhance certain characteristics of the GPR data are presented. The results show the SSA based algorithms are well suited to impulse GPR data processing. SSA method applied to data makes GPR images more acceptable for initial interpretation and data evaluation.
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In this work Bistatic Inverse Forward Scattering Inverse Synthetic Aperture Radar (BFISAR) concept is addressed. Geometric description of BFISAR topology with stationary transmitter and receiver, and moving target is given. Kinematic... more
In this work Bistatic Inverse Forward Scattering Inverse Synthetic Aperture Radar (BFISAR) concept is addressed. Geometric description of BFISAR topology with stationary transmitter and receiver, and moving target is given. Kinematic vector equations are derived. BFISAR signal mathematical model with short pulse modulation is described. It is proven that BFISAR signal formation and image reconstruction can be interpreted as direct
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In this paper, different Constant False Alarm Rate (CFAR) detectors (Cell Averaging (CA), Greatest Of (GO), Smallest Of (SO) and Order Statistic (OS)), are proposed and studied in the presence of strong urban pulse interference. The... more
In this paper, different Constant False Alarm Rate (CFAR) detectors (Cell Averaging (CA), Greatest Of (GO), Smallest Of (SO) and Order Statistic (OS)), are proposed and studied in the presence of strong urban pulse interference. The detection performance of the CFAR is studied for Swerling II target model. Also is studied the detection probability of these different types of CFAR detectors. The experimental results are obtained by simulation analysis in MATLAB computational environment. The obtained results for these CFAR detectors can be used in both, radar and communication receiver networks.
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In this paper we present the research results concerning the performance of Hough detector with an Order Statistic False Alarm Rate (OS CFAR) processor, in the presence of randomly arriving impulse interference with Poisson distributed... more
In this paper we present the research results concerning the performance of Hough detector with an Order Statistic False Alarm Rate (OS CFAR) processor, in the presence of randomly arriving impulse interference with Poisson distributed flow and Raleigh amplitude distribution. In the presented contribution are investigated two types of Hough detectors with CFAR processors, in order to choose the most efficient one in the presence of clutter and randomly arriving impulse interference. The Hough detector with OS CFAR processor is compared to Hough detector with CA CFAR processor. The achieved results reveal that the Hough detector with the OS CFAR algorithm is more effective. The experimental results are obtained by numerical analysis. We have studied the detection probability and the average decision threshold of Hough detector with two types of CFAR processors. The results show that the use of this structure of Hough detector allows drastically reducing the detectability losses in co...
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We present in this paper the research results concerning the performance of an Excision Constant False Alarm Rate (EXC CFAR) detector and an EXC CFAR Binary Integration (BI) detector with Hough transform in the presence of randomly... more
We present in this paper the research results concerning the performance of an Excision Constant False Alarm Rate (EXC CFAR) detector and an EXC CFAR Binary Integration (BI) detector with Hough transform in the presence of randomly arriving impulse interference with binomial distributed flow and Raleigh amplitude distribution. We have studied the detection probability and the average decision threshold of EXC CFAR detectors with Hough transform. The experimental results are obtained by numerical analysis. They reveal that the use of Hough transform allows reducing drastically detectability losses in comparison to the conventional EXC CFAR detector and that it is effective for small signal-to-noise ratios. The research work is performed in MATLAB computational environment. The obtained analytical results for excision Hough CFAR detectors can be used in both, radar and communication receiver networks.
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The aim of this article is to test the effectiveness of the known structures of radar signal processing (RSP) that employ CFAR processors in order to detect moving targets in the frequency domain, depending on the chosen width of velocity... more
The aim of this article is to test the effectiveness of the known structures of radar signal processing (RSP) that employ CFAR processors in order to detect moving targets in the frequency domain, depending on the chosen width of velocity channels (the number of FFT). The Doppler radar is radar with continuous transmission of PSP (Phase Shift Keying) signals. Real records that have been produced by Doppler radar for the case of moving people or cars on the background of trees are used in the study. The results obtained lead to believe that detection of targets with CA CFAR processors provides the required effectiveness in case when the velocity channel width is correctly defined.
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In this paper we research one original structure of the CFAR detector and made a parameter estimation of the moving marine targets at the background of a sea clutter using Bistatic Forward Scatter Radar (FSR) system. The specific two... more
In this paper we research one original structure of the CFAR detector and made a parameter estimation of the moving marine targets at the background of a sea clutter using Bistatic Forward Scatter Radar (FSR) system. The specific two pulse MTI CFAR processor with K/M-L batch processor and parameter estimator for a marine target with unknown size are investigated on the base of real data records. The data itself t have been gathered by the team of the Birmingham University using in-house developed FSR.
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ABSTRACT
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In the present paper the target elevation error is estimated. VHF radar and a three- antenna positioned one above the other is used. The sensitivity of the elevation finding algorithm versus the coefficient of reflection, variation of... more
In the present paper the target elevation error is estimated. VHF radar and a three- antenna positioned one above the other is used. The sensitivity of the elevation finding algorithm versus the coefficient of reflection, variation of input signal amplitude and phase is studied. Mean square error of elevation estimation versus target range and elevation is obtained.
In this paper, two multi-sensor approaches for measuring the radar target elevation in the VHF range are studied and compared. The first approach is the classic trilateral approach, described by Caspers. It measures the target altitude... more
In this paper, two multi-sensor approaches for measuring the radar target elevation in the VHF range are studied and compared. The first approach is the classic trilateral approach, described by Caspers. It measures the target altitude using three independent measurements of a target range. The second approach is the interferential multipath lobbed approach, described by Chen. The difficulty in doing comparison rises from the difference between these approaches and the difference between sensor parameters used by the two methods. Therefore, our goal is to compare the two methods in the same operating conditions - space-power conditions and technical conditions (accuracy of target range measurement). The investigation is performed by Monte-Carlo simulation, and the statistical results are obtained for the confidence interval of 0.95. The results obtained allow concluding that the potential accuracy of both methods is nearly the same regardless of the difference between them. However,...
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AbstractThe data fusion problem is important in the process of building up multiple sensors system for detection of target and trajectories. In this paper, we research a multisensor data fusion approach that uses the polar Hough... more
AbstractThe data fusion problem is important in the process of building up multiple sensors system for detection of target and trajectories. In this paper, we research a multisensor data fusion approach that uses the polar Hough transform (PHT). After every one radar scan ...
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ABSTRACT Based on theoretical methods for synthesis of complementary signals briefly below, the authors have developed a new algorithm and software for automated synthesis of Direct sequence complementary codes. The authors propose a... more
ABSTRACT Based on theoretical methods for synthesis of complementary signals briefly below, the authors have developed a new algorithm and software for automated synthesis of Direct sequence complementary codes. The authors propose a numerical method for analysis and comparison of this types synthesize Complementary codes with well – know code sequences like Barker and Z-complementary codes. Build on the autocorrelation and ambiguity functions of signals, the numerical method estimates the volume of sidelobes separately for each signal. The results are obtained using the specialized software in MATLAB R2007b.
ABSTRACT Not Available
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The article analyses the possibility of the forward scatter radar method for detecting large-sized cosmic objects when using emission of the Sun as probing signals. The method of the forward scatter radar is based on the phenomenon of a... more
The article analyses the possibility of the forward scatter radar method for detecting large-sized cosmic objects when using emission of the Sun as probing signals. The method of the forward scatter radar is based on the phenomenon of a significant increase the bistatic target radar cross section when the probe signal is scattered forward, i.e. along direction of the principal beam of locator pattern.
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The feasibility of an X-ray Forward Scatter Radar (FSR) system, which exploits X-ray pulsars as opportunity transmitters, is examined. We provide a power budget estimate for detection of large cosmic objects using such a FSR system and... more
The feasibility of an X-ray Forward Scatter Radar (FSR) system, which exploits X-ray pulsars as opportunity transmitters, is examined. We provide a power budget estimate for detection of large cosmic objects using such a FSR system and assume the use of the high-resolution X-ray telescopes mounted on a satellite as the receivers. The numerical results are obtained for three types of pulsars and small asteroids, whose diameters equal and overcome 50m.
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The paper explores the shadows created by moving humans in two types of Forward Scatter (FS) systems, which use GPS signals and sound signals. The comparative analysis of results is based on the correlation analysis and focused on... more
The paper explores the shadows created by moving humans in two types of Forward Scatter (FS) systems, which use GPS signals and sound signals. The comparative analysis of results is based on the correlation analysis and focused on establishing of relationships between different types of shadows. The results show whether it is possible to use sound barriers for detection of moving objects.
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ABSTRACT This paper focuses on the Time of Arrival (TOA) estimation problem related to new application of pulsar signals for airplane-based navigation. The aim of the paper is to propose and evaluate a possible algorithm for TOA... more
ABSTRACT This paper focuses on the Time of Arrival (TOA) estimation problem related to new application of pulsar signals for airplane-based navigation. The aim of the paper is to propose and evaluate a possible algorithm for TOA estimation that consists of epoch folding, filtering, CFAR detection, crosscorrelation and TOA calculation. The TOA estimation algorithm proposed is verified using real experimental data obtained from the Westerbork radio observatory in The Netherlands. The performance of the proposed TOA algorithm is evaluated in terms of SNR at the cross-correlator input and the TOA accuracy.
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A new parallel algorithm for signal processing and a parallel systolic architecture of a CFAR processor with adaptive post detection integration (API) are presented in this paper. The processor proposed is used for effective target... more
A new parallel algorithm for signal processing and a parallel systolic architecture of a CFAR processor with adaptive post detection integration (API) are presented in this paper. The processor proposed is used for effective target detection in a single range resolution cell of a radar when echoes from small airborne targets are performed in conditions of pulse jamming. The main
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The paper studies an extremely important and promising scientific issue, namely the question of determining the coordinates of moving objects and their navigation in space. For this purpose, we propose a conceptual model of a multi-sensor... more
The paper studies an extremely important and promising scientific issue, namely the question of determining the coordinates of moving objects and their navigation in space. For this purpose, we propose a conceptual model of a multi-sensor navigation system, based on a navigation system using pulsar signals. An approximate model of pulsar navigation system is presented as well.
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The paper analyses the possibility of Forward Scatter Radar (FSR) systems to detect airplanes using cosmic emission from pulsars and planets (pulsar, Sun, Moon). A suboptimal multichannel algorithm for joint detection and evaluation of... more
The paper analyses the possibility of Forward Scatter Radar (FSR) systems to detect airplanes using cosmic emission from pulsars and planets (pulsar, Sun, Moon). A suboptimal multichannel algorithm for joint detection and evaluation of the parameters of the forward scattering signal created by an airplane (duration and velocity) is proposed, with preliminary compensation of the powerful direct signal emitted by cosmic sources (pulsar, Sun and Moon). The expressions for calculation of the Signal-to-Noise Ratio (SNR) at the input of the detector and the compensator are obtained. The detection characteristics are also obtained, and the requirements for the suppression coefficient of the compensator are evaluated. A methodology for calculating the maximum distance for detecting an aircraft using a described algorithm is proposed. The obtained results show that due to the Forward Scatter (FS) effect, there is the theoretical possibility to detect airplanes at close ranges by FSRs, which ...
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The feasibility of asteroid detection using the Forward Scatter Radar Network that exploits three pulsars as transmitters is examined. We provide a power budget estimate for asteroid detection using such a FSR-network with the radio... more
The feasibility of asteroid detection using the Forward Scatter Radar Network that exploits three pulsars as transmitters is examined. We provide a power budget estimate for asteroid detection using such a FSR-network with the radio telescope used as a receiver. The numerical results are obtained for two known radio telescopes in the Netherland and three known pulsars.
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Bistatic Forward Scattering Inverse Synthetic Aperture Radar (BFISAR) concept is discussed. BFISAR kinematics and topology with a stationary transmitter and receiver, and moving target are described. BFISAR signal formation and image... more
Bistatic Forward Scattering Inverse Synthetic Aperture Radar (BFISAR) concept is discussed. BFISAR kinematics and topology with a stationary transmitter and receiver, and moving target are described. BFISAR signal formation and image reconstruction are analytically described. Theoretical constraints and BFISAR basic parameters are defined. To verify mathematical models numerical and natural experiments are carried out.
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Two detection algorithms (heuristic and CFAR) for target detection in pulsar FSR are analyzed using the simulation approach. The simulation results are verified by processing of the experimental data obtained by the radio observatory... more
Two detection algorithms (heuristic and CFAR) for target detection in pulsar FSR are analyzed using the simulation approach. The simulation results are verified by processing of the experimental data obtained by the radio observatory Dwingeloo in the Netherlands. The simulation and experimental results proved that the CFAR detection algorithm is more effective than the heuristic algorithm and can be successfully used in a pulsar FSR system for protection of air space from unwanted air objects.
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An approach and algorithm are proposed for separating the useful signal from a moving cosmic target and the direct signal transmitted by GPS satellites, on the background of the receiver noise. The algorithms for separating the useful... more
An approach and algorithm are proposed for separating the useful signal from a moving cosmic target and the direct signal transmitted by GPS satellites, on the background of the receiver noise. The algorithms for separating the useful signal will be based on the principle of separation in speed of two GPS signal sequences, the first — with a satellite velocity (reference signal), the second — with the target velocity. We will evaluate their performance with computer calculation or simulation.
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... Using the Hough Transform * Vera Behar1, Lyubka Doukovska2, and Christo Kabakchiev2 ... The slope of the target trajectory presented in Fig.1 is determined by the radial velocity of the target: V = (j2 − j1)δR (i2 − i1)tsc = tan θ δR... more
... Using the Hough Transform * Vera Behar1, Lyubka Doukovska2, and Christo Kabakchiev2 ... The slope of the target trajectory presented in Fig.1 is determined by the radial velocity of the target: V = (j2 − j1)δR (i2 − i1)tsc = tan θ δR tsc , (3) ...
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The aim of this article is to test the effectiveness of the known CFAR processors in order to detect moving targets in the frequency domain of real records. The purpose is to be chosen optimal CFAR detector for moving target detection.... more
The aim of this article is to test the effectiveness of the known CFAR processors in order to detect moving targets in the frequency domain of real records. The purpose is to be chosen optimal CFAR detector for moving target detection. The data are obtained by portable, surveillance, Frequency Modulated Continuous Wave (FMCW) radar with Low probability of Intercept (LPI). In the paper are studied and compared CA, OS, SO, GO CFAR processors.
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In this paper we study the efficiency of CA CFAR BI, EXC CFAR BI and Adaptive CFAR PI detectors in strong pulse jamming. We achieve new results for the average decision threshold (ADT) using the minimum detectable signal (Pd=0.5). For... more
In this paper we study the efficiency of CA CFAR BI, EXC CFAR BI and Adaptive CFAR PI detectors in strong pulse jamming. We achieve new results for the average decision threshold (ADT) using the minimum detectable signal (Pd=0.5). For comparison we use also the approach with Monte-Karlo simulation for estimation of the ADT of the studied CFAR detectors. Differently from other authors, we consider the entire range (0 to 1) of the probability for the appearance of pulse jamming in range cells.
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A new parallel algorithm for signal processing and a parallel systolic architecture of a CFAR processor with adaptive censoring and post detection integration (API) are presented in the paper. The processor proposed is used for target... more
A new parallel algorithm for signal processing and a parallel systolic architecture of a CFAR processor with adaptive censoring and post detection integration (API) are presented in the paper. The processor proposed is used for target detection when echoes from targets are performed in conditions of binomial distribution pulse jamming. The property of the algorithm proposed is its ability automatically to determine and censor the unwanted samples corrupted by pulse jamming in both, the two-dimensional reference window and the test cell, before noise level estimation. In case of binomial distribution pulse jamming for big repetition frequency, the censoring capabilities of the algorithm offered from Behar is small and the probability of false alarm is not constant. We offer the vector at the output of the reference window to be sorted and censored again. In such a way the influence of pulse jamming environment over adaptive threshold is reduced to minimum. The systolic architecture o...
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In this paper we study one original algorithm realized in the frequency domain for detection and parameter estimation of moving marine targets on the background of real interference in a Bistatic Forward Scattering Radar (FSR) system. The... more
In this paper we study one original algorithm realized in the frequency domain for detection and parameter estimation of moving marine targets on the background of real interference in a Bistatic Forward Scattering Radar (FSR) system. The specific two-pulse MTI CFAR processor which includes a K/M-L batch processor for detection of a marine target with unknown size and a parameter estimator of both target energy spectrum and Doppler frequency, is investigated on the base of real data records that have been obtained by the team of the Birmingham University using Forward Scattering Radar.
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Stars have been used -in what is called celestial navigation- since thousands of years by mankind. Celestial navigation was used extensively in aviation until the 1960s, and in marine navigation until recently. It has been investigated... more
Stars have been used -in what is called celestial navigation- since thousands of years by mankind. Celestial navigation was used extensively in aviation until the 1960s, and in marine navigation until recently. It has been investigated for agriculture applications, utilized for military aircraft and, presumably, for intercontinental ballistic missiles. Recently the interest in celestial navigation has sparked again with an emphasis on deep space navigation using pulsars. Pulsars are fast rotating neutron stars that emit electromagnetic radiation, which is received anywhere in our solar system as a series of very stable fast periodic pulses. A number of studies have been performed on navigating using pulsar signals; the first study performed by NASA in 1974 focused on radio pulsars, but in later years most attention was given to X-ray pulsars. Radio pulsar navigation - utilizing signals which could be detected on Earth - has not received much attention, since the signal strength of r...
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In this paper, one possible algorithm for air target detection and velocity estimation in a pulsar FSR system is proposed. In this processing algorithm, one approaches for extraction with nonlinear element of the target signal from the... more
In this paper, one possible algorithm for air target detection and velocity estimation in a pulsar FSR system is proposed. In this processing algorithm, one approaches for extraction with nonlinear element of the target signal from the input mixture "direct pulsar signal + reradiated target signal" are studied. The signal processing algorithm is evaluated by computer simulation.