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This paper extends the concept of autofocus in SAR processing procedure and proposes an adaptive algorithm for SAR data focusing. The novel algorithm discards the hypothesis in the autofocus algorithms, i.e. the range migration has been removed perfectly, and moves the ldquoadaptiverdquo processing to the front of RCMC. By adjusting the parameters for focusing adaptively, the range migration in the...
Numerous space-borne X-band synthetic aperture radars (X-SAR) systems will be launched by European agencies in the coming decade commencing this year. Those X-SARs can measure precipitation over land, thereby significantly augmenting the sensors that comprise the Global Precipitation Mission (GPM). This will incur relatively little incremental cost because they have already been funded. X-SAR measurements...
Tuscany regional government has improved the real time weather monitoring system by setting up a regional weather radar network, to provide an useful hydro-geological risk reduction instrument to the civil protection emergency system. The fully automated regional radar network is constituted by three ARIES-C systems which are fully coherent Doppler weather radars, operating in C-band with very reduced...
Radar measurements of a radar calibration sphere test target suspended in sea surface multipath propagation conditions are reported. Wideband measurements together with high range resolution (HRR) processing were employed to resolve the direct reflection component and sea surface reflected multipath components of the received signal. The temporal correlation characteristics of the resolved single...
The noise radar concept can be extended to an array of K transmit antenna and M receive antenna. When independent noise sources are transmitted from each antenna the approach may be viewed as a special case of MIMO radar and matched filters may be derived. In this contribution statistical properties of matched filters for MIMO noise radar are derived. For any array the concepts of the sum and difference...
It is natural to approach multi-channel SAR in terms of spatial diversity concepts developed for multiple-input-multiple-output (MIMO) communications and recent advances in MIMO radar. We introduce the MIMO SAR concept in this paper, and the goal here is to research the concept and potential design of a new SAR application based on MIMO theory and techniques. MIMO technology which were develop originally...
Conformal arrays possess certain desirable characteristics for deployment on unmanned aerial vehicles and other payload-limited platforms: aerodynamic design, minimal payload weight, increased field of view, and ease of integration with diverse sensor functions. However, the conformal arraypsilas nonplanar geometry causes high adaptive losses in conventional space-time adaptive processing (STAP) algorithms...
Bistatic radar has a history which dates back to the very earliest days of radar itself. It has been remarked that interest in bistatic radar has been cyclic, with a period of about fifteen years. Numerous experimental systems have been built and evaluated, though rather fewer operation systems. The purpose of this paper is to present and discuss recent developments that indicate that bistatic systems...
In this paper a technique to conduct tomographic analyses of forested areas through multiple, coherent SAR images is presented. This technique differs from other methods existing in literature in that it may be regarded as a natural extension of SAR interferometry to the case where several distributed targets are present within the system resolution cell. In this way, it is possible to estimate the...
Synthetic aperture radar raw data simulation serves many purposes such as testing different image formation algorithms, studying the interaction of electromagnetic waves with a scene being imaged, testing and validating different system design parameters, etc. Frequency domain raw data simulation can be used to generate the raw data efficiently, as compared to time domain simulation. However, contrary...
In this paper we apply a data association in track-before detect (TBD) with a polar Hough transform (PHT) in a radar network. The proposed algorithm is applied in multiple input multiple output (MIMO) radar system. We study the sensitivity of TBD multi-radar system as a function of the errors of target trajectory parameters measurement. The results are obtained in the presence of Randomly Arriving...
The availability of long sequences of SAR data virtually at any location on the Earth allows an extensive evaluation of land cover dynamics, which is a well-known extension to image pair multitemporal analysis. In this work we show the first results of an extensive evaluation of one among these ldquohypertemporalrdquo SAR sequences, with a stress on urban area monitoring.
New operational requirements for stealth targets detection in dense & inhomogeneous clutter are emerging (littoral warfare, low altitude asymmetric threats, battlefield in urban area...). Classical radar approaches for Doppler & array signal processing have reached their limits. We propose new improvements based on advanced mathematical studies on geometry of SPD matrix (symmetric positive...
Circular shifting and windowing have been introduced to improve the performance of Doppler centroid tracking (DCT) in inverse synthetic aperture radar (ISAR) image focusing when the target has prominent scattering centers. However, the conventional unified windowing method is hard to implement and affects the performance of DCT. An adaptive windowing method based on ISAR target extraction is proposed...
Speckle reduction is a prerequisite for many synthetic aperture radar (SAR) image processing tasks. In recent years, the hidden Markov tree (HMT) in wavelet domain is widely used for speckle reduction. The HMT model captures the persistence property of wavelet coefficients, but lacks the clustering property of them within a scale, whereas the Gaussian Markov random field (GMRF) model can characterize...
In radar imaging, it's well known that relative motion or deformation of parts of illuminated objects induce additional features in the Doppler frequency spectra. These features are called micro-Doppler effect and appear as sidebands around the central Doppler frequency. They can provide valuable information about the structure of the moving parts and may be used for identification purposes. Previous...
Synthetic aperture radar (SAR) is active and coherent microwave high resolution imaging system, which has the capability to image in all weather and day-night conditions. SAR transmits chirp signals and the received echoes are sampled into In-phase (I) and Quadrature (Q) components, generally referred to as raw SAR data. Raw data compression is an essential future requirement for high resolution space...
In this paper, the residue is extended to the second order, which is called second order residue. Second order residue is researched and applied in the interferometric synthetic aperture radar (SAR) phase unwrapping. Similar to the residue, the second order residue reflects the discontinuity in the wrapped phase. In phase unwrapping, the traditional residue is normally used to form the branch cut...
This paper explores the use of implementing deception waveforms in the space-time adaptive processing (STAP) model for efficient waveform optimization in hardware-in-the-loop simulation. By understanding range gate pull-off (RGPO) techniques developed in a generic form, velocity gate pull-off (VGPO) technique models can be explored in a similar manner. The VGPO mathematical models are developed using...
The current development of the high resolution concept allows to redefine standard applications of radars, like the measurement of the motion parameters of road traffic. High resolution radars may be used to monitor the road traffic. In this paper, live captures from a high resolution linear frequency modulated continuous wave (LFMCW) millimeter-wave radar are shown. For the estimation of the dynamics...
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