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In this paper, we consider the motion parameter estimation of ground moving targets in a multistatic passive airborne radar that utilizes broadcast signals as a source of opportunity. It is shown, by focusing on the target position or within its close vicinity, that the narrow signal bandwidth permits the use of a moderate coherent integration time without range migration compensation. The multistatic...
We consider adaptive detection of a signal embedded in additive disturbance whose multivariate distribution belongs to a very general class, including many statistical models commonly adopted for radar interference. We introduce the concept of generalized Constant False Alarm Rate (CFAR) and show that a class of receivers sharing some invariances complies with the quoted property. Then, we devise...
The Active Antennas (AESA) technology has dramatically increased the operational capability of modern radars. Nevertheless, minimize production costs and cost of ownership of these systems is also a major industrial objective. The paper is organized in two parts. The first one deals with improvements achieved so far for reducing the costs and the complexity of industrial testing. In the second part,...
This work investigates the target localization capabilities of a multiple input multiple output (MIMO) radar with multiple widely separated transmit and receive sensor arrays. The corresponding Cramer-Rao lower bound (CRLB) is derived for noncoherent estimation of a target's location. The derived CRLB can be seen as a generalization of the CRLB for a monostatic radar with a single sensor array. It...
This paper deals with the problem of adaptive radar detection when a limited number of training data, due to environmental heterogeneity, is present. We suppose that some a-priori spectral models for the interference in the cell under test are available and determine Generalized Likelihood Ratio Test (GLRT) based detection algorithms. The basic idea is to model the actual interference inverse covariance...
This paper deals with the distribution of signal received by airborne radar in Doppler domain for maritime surveillance mission. It is composed of thermal noise and sea clutter which its intensity may be described by a compound K-distribution. The data used was recorded in high range and Doppler resolution by monostatic coherent X-band radar above Mediterranean sea and Atlantic ocean. The statistics...
For synthetic aperture imaging of through-wall-radar, the multi-path propagation between target and walls introduces the ghosts into the formed image. This paper proposes a new algorithm for suppressing these multi-path ghosts. A multi-path model in an enclosed building is first developed. By analyzing the model, we obtain an important feature of the multi-path ghosts to be defined as aspect dependence...
We consider the problem of multi-frame target detection in radar systems‥ The Detector and Plot Extractor, operating on a scan-by-scan basis, provides a list of candidate detections (or plots) to a Track-before-detect (TBD) Processor, which correlates data over multiple scans (or frames) before taking the final decision as to the target presence. A new dynamic programming algorithm to implement the...
This paper mainly addresses the through-wall life-sign detection with the low signal-to-noise ratio in the Gaussian background. A novel detection approach based on fourth-order cumulant is proposed to extract the weak life-sign such as human breathing. First, MTI is adopted to reduce the zero-frequency clutters including wall echoes. Then, according to the characteristic of suppression for Gaussian...
The ICE-SAIS project uses Space-based Automatic Identification System (S-AIS) data in conjunction with satellite Synthetic Aperture Radar (SAR) imagery for Ship and Iceberg Monitoring. The objectives of this work are to exploit S-AIS data for collecting groundtruth to improve existing ship/iceberg discrimination algorithms and to demonstrate the utility of S-AIS data for operational iceberg surveillance...
In recent years there have been two significant and related developments that seem set to lead to new and improved radar capability. These are: (i) diversity, in the form of highly flexible digital technology and (ii) the early adoption of intelligent or cognitive processing techniques. Together these provide a powerful combination that are helping to pave the way to intelligent adaptive radar networks...
Inverse synthetic aperture radar imaging of moving targets with a stepped frequency waveform presents unique challenges. Intra-step target motion introduces phase discontinuities between frequency bands, which in turn produce degraded range side lobes. Frequency stitching of the stepped-frequency waveform to emulate a contiguous bandwidth can dramatically reduce the effective pulse repetition frequency,...
In this paper, we discuss the advantages and limitations of coherent multiple-input multiple-output (MIMO) radars. This is a radar system in which the transmit and receive elements are in relative close proximity so that the target response is coherent between transmit and receive antenna pairings up to a known geometric effect. In particular, we compare the performance of MIMO radars that employ...
This paper investigates the methodology of applying the spatial integration approach (SIA) to the scattering coefficient retrieval from GNSS-R signals for sea surface oil slick detection. The SIA has been traditionally used in the generation of simulated Delay-Doppler Maps, which emphasizes the power contribution of every sea surface point. While in this paper, the SIA is applied to the scattering...
Statistical model for high resolution sea clutter, which we called the compound Inverse Gaussian distribution (CIG), is proposed. The model is a mixture of the Rayleigh distribution and the Inverse Gaussian distribution to model the speckle and the texture components respectively. The proposed distribution is extended to cover the additive thermal noise to achieve a good match to real data. The overall...
Phase only transmit nulling may help the next generation of radar systems operate in an over-crowded RF spectrum. Open air experimental results from an eight-channel X-band radar test bed are presented that demonstrate an approach for generating constant modulus waveforms that possess spatial nulls when transmitted from an antenna array. The Re-iterative Uniform Weight Optimization (RUWO) algorithm...
We design a parametric multicarrier phase-coded (MCPC) waveform that achieves the optimal performance in detecting an extended target in the presence of signal-dependent interference. Traditional waveform design techniques provide only the optimal energy spectral density of the transmit waveform and suffer a performance loss in the synthesis process of the time-domain signal. Therefore, we opt for...
The pulse time of arrival is an important parameter estimated in an electronic warfare receiver. The Cramér-Rao bound provides a lower bound on the variance of unbiased parameter estimates. In the past, time of arrival performance has been compared to a bound derived under Gaussian assumptions. However, these estimates are frequently computed from the pulse envelope, which exhibits Rician statistics...
Frequency estimation algorithms are utilized to find target doppler frequency accurately in radars using DFT/FFT doppler filter-banks and target range in FMCW radars. Although there are many different single-tone frequency estimation methods published in the literature, the algorithms that combine few of the DFT/FFT coeffients around the target frequency with simple arithmetic operations are of interest...
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