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It is well known that ultra-wideband (UWB) noise radar achieves high-resolution imaging of targets and terrain. The wide bandwidth yields fine range resolution, while the noise waveform provides immunity from detection, interference, and interception. Having multiple noise radars networked with each other provides significant benefits in target detection and recognition. We propose a scheme to modify...
Far-field target detection, multi-sensor communications, and security are essential requirements of first-emergency networks. A radar-communications system is a potential opportunistic spectrum access (OSA) solution, harnessing the coexisting advantages of radio detection and ranging (RADAR), and wireless communications. A multi-functional waveform has been designed, by embedding an Orthogonal Frequency...
High resolution radar system usually has a massive amount of raw data, so we have to carry out data fusion as quickly as possible. In this paper, we propose a fast clustering algorithm based on single dimensional distance calculation. The proposed algorithm divides raw data into subsets by single dimensional distance, and then merges subsets according to single dimensional distance and set-density...
Side lobe suppression is extremely important in precisely determining the weak echo scattering region in the presence of range side lobes. This paper addresses the signal design problem for the detection of multiple/distributed targets in high resolution radar (HRR) application with improved side lobe suppression ratio. The simulation results indicate a significant improvement in terms of noise tolerance...
In this paper, the target magnitude signature and Doppler signature characteristics are analyzed in detail. Based on the Doppler signature, the target motion parameters can be extracted. Combining the magnitude signal and Doppler signal, the target convoy resolutions in ground forward scattering radar (FSR) are analytically obtained, which is different from the conventional shadow inverse synthetic...
An iterative range profile estimation process is derived for Golay waveforms. The Re-Iterative Super Resolution (RISR) algorithm is used in conjunction with Golay waveforms and processing for radar range-Doppler estimation. Various additional range-Doppler estimation methods that use RISR and Golay waveforms and processing are simulated for the sake of comparison. Range and Doppler sidelobes are seen...
This paper deals with the optimal radar waveform design problem using the quadratically constraint quadratic programing (QCQP) in the narrowband signal echo to range-doppler extended target regime. The solution is obtained in the sense of signal to interference plus noise ratio(SINR) maximization with resolution and fixed transmit power constraints. The performance is compared with other conventional...
Modern SAR systems have high resolution which leads the backscattering clutter to be non-Gaussian. In order to properly classify images from these systems, a non-Gaussian noise model is considered: the SIRV model. A statistical test of equality of covariance matrices is used to classify pixels, taking into account the critical region of the test which rejects the likeliness of a covariance matrix...
In this study, an iterative maximum a posteriori (MAP) approach using a Bayesian model of Markovrandom field (MRF) was proposed for despeckling images that contains speckle. Image process is assumed to combine the random fields associated with the observed intensity process and the image texture process respectively. The objective measure for determining the optimal restoration of this “double compound...
The document describes a detection and inherent ambiguity resolution scheme for Medium-PRF waveforms. Medium-PRF waveforms are characterized by ambiguous measurements of both range and doppler. Ambiguities are resolved by changing the pulse repetition frequency (PRF) from burst to burst and by combining the ambiguous results of adjacent bursts. The classical binary integration procedure applies a...
Modern operational and/or high resolution SAR satellite missions impose stringent requirements on on-board data compression such as a higher data reduction ratio, more flexibility, and faster data throughput. A novel approach is Flexible Dynamic Block Adaptive Quantization (FDBAQ). This method outperforms currently used Block Adaptive Quantization with respect to Signal-to-Noise-Ratio related to the...
In this paper statistical approach to synthesize algorithms for digital signal processing in UWB noise radar and sodar is used. Nonparametric copula based detection algorithms are suggested. Multiple input multiple output case is investigated. Monte-Carlo simulation for suggested algorithm is done. Experimental check is done on the basis of developed acoustic physical model which is used to build...
In this paper, we propose a modified filtering algorithm to the Lopez and Fabregas [6] noise reduction algorithm for the interferometric phase noise in SAR interferometry using a multiresolution approach. Our contribution to the existing algorithm consists on the exploitation of the InSAR coherence map in order to generate a more adaptive mask for each decomposition level. The developed algorithm...
Comparison of resolution and a side lobe level on delay (range) and azimuth in UWB noise radar with linear equidistant transmitting antenna array and the single receiving antenna is submitted at presence and absence of signal recirculation in a feedback loop transmitting element - target - receiving element.
In the radar system, modelling and simulation can guarantee the high reliability and correctness of system design, shorten designing period and reduce development cost. This paper discusses signal processing system of the SFR (stepped-frequency radar), especially the several key processing steps to get the HRRP (high resolution rang profile). The system simulation has done based on LabVIEW (Laboratory...
We present a high resolution method for spotlight mode SAR imaging that utilizes pole/residue modeling of projected target reflectivity density function and tomographic reconstruction. Utilization of a matrix pencil method (MPM) allows super resolution to be achieved in range for a single imaging angle. Hence the quality of the image reconstructed is also improved. It is shown that the method is very...
A stylized compressed sensing radar is proposed in which the time-frequency plane is discretized into an N by N grid. Assuming that the number of targets K is small (i.e. KLtN2), then we can transmit a sufficiently ldquoincoherentrdquo pulse and employ the techniques of compressed sensing to reconstruct the target scene. A theoretical upper bound on the sparsity K is presented. Numerical simulations...
This paper considers the problem of high-resolution imaging of the environment formalized in terms of a nonlinear ill-posed inverse problem of nonparametric estimation of the power spatial spectrum pattern (SSP) of the wavefield scattered from an extended remotely sensed scene (referred to as the scene image) via processing the discrete measurements of a finite number of independent realizations of...
Traditionally, moving target indication (MTI) modes tailored to wide-area surveillance (WAS) have employed waveforms with bandwidths matched to the range extent of targets of interest. Matching range resolution to expected vehicle lengths serves to minimize interfering clutter returns while preserving available target power, thereby maximizing target probability-of-detection. Recent advances in waveform...
Multiscan data association can significantly enhance tracking performance in critical radar surveillance scenarios involving multiple targets, low detection probability, high false alarm probability, evasive target maneuvers and finite radar resolution. Unfortunately, however, this approach is affected by the curse of dimensionality which hinders its real-time application for tracking problems with...
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