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In this paper, the development of a stationary SAR receiver system using TerraSAR-X as transmitter is described. First the bistatic geometry and expected resolution are considered. After giving an overview of the hardware setup, the expected performance of the system is evaluated. The paper ends with the processed results of a measurement campaign performed in summer and fall 2009, and a comparison...
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...
This paper discusses methods and parameter settings that help to estimate texture in SAR images. In general, this is a difficult task for SAR images that are characterized by speckle noise and which span a wide range of pixel magnitudes. We applied Gauss Markov Random Field (GMRF) models and Enhanced Model Based Despeckling (EMBD) to 1 meter resolution amplitude images of the German TerraSAR-X mission...
We have shown that area-averaged structure orientation angles relative to incident angle of POLSAR in urban area can be estimated from argument of correlation coefficient of circularly-polarized observation bases. It is quite interesting that by this approach we can estimate area-averaged urban parameters even if we can not distinguish them from conventional received signal component intensity map...
Thanks to the signal processing applied to radar signal, radar systems can provide images with a very high resolution. With regard to these properties, one can estimate that radar images are used to get elevation terrain considering the basic characteristics of a radar image. This paper examines one way to produce DEM (Digital Elevation Models) from a mountainous area (the French Alps). So, we organize...
The TerraSAR-X SAR system provides high spatial resolution and geometric accuracy imagery which supports well the mapping of the 3-D structure of large-scale civil infrastructure and its motions (4-D). In this work, we investigated the potential of TerraSAR-X observations for monitoring rapid land subsidence induced by reclamation activities. A case study was conducted in Hong Kong Disneyland Theme...
As an essential approach of SAR image interpretation, a good pose estimation calls for two conditions: an accurate extraction of the scattering centers and a thorough exploration of the structural information among them. The article focuses on these two topics successively. Firstly, the power spectrum estimation methods are recommended to improve the scattering center resolution and the Minimum Variance...
Space-surface bistatic synthetic aperture radar (SS-BSAR) has gained more and more researcher's interests. In this paper, we focus on improving range resolutions of GNSS illuminator based SS-BSAR with the method of spectrum synthesis of ultra-wide-band (UWB). Narrow bandwidth signals, such as GPS P code, can be spliced into a wider signal. Simulation results show that it can effectively increase signal...
A new concept for change detection algorithm for urban areas affected by earthquake is here presented. It is characterized as applicable to just one post-event amplitude Synthetic Aperture Radars (SAR) image and employs the inversion of sound scattering models already introduced in literature by the same authors. Aim of the algorithm is to try obtaining fast mapping of damaged areas and provide a...
Wavelet transform is a new applied signal processing technique in recent years, its time-frequency multi-resolution and signal processing performance are analyzed in the paper. A practical ground penetrating radar signal processing method based on wavelet transform is proposed; it contrast with continuous wavelet transform, the experiments indicate that it improves the processing performance of underground...
An algorithm based on compressive sensing (CS) is proposed for synthetic aperture radar (SAR) imaging of moving targets. The received echo is decomposed into the sum of many basis sub-signals that are generated by discretizing the target spatial domain and velocity domain and synthesizing the SAR received data for every discretized spatial position and velocity candidate. In this way, the SAR imaging...
The characteristic of radar video is analyzed in detail. The design and implementation of high resolution radar video transfer system are described. And the experiment is performed. The experimental results have revealed that the high efficient compression coding of radar video is achieved and the high resolution of echo signal is assured. The system has good practicability.
The theoretical result shows that the self-correlation function not only has the time-shift invariant feature, but also largely reduces the computational work. To overcome the sensitivity of High-Resolution Range Profile(HRRP), this paper has extracted the self-correlation function of HRRP as a feature for target recognition. Templates and test data are created by using the measured data of sea targets...
Millimeterwave radar sensors are netted to cover a sufficient region of an airport and deliver as well information on position as classification of debris. To be able to miniaturize the antenna assembly, which is critical for the vicinity of a runway, the 220-GHz radar band is used. Use of this band also allows to achieve a wide signal bandwidth and consequently a high range resolution.
The principals of range resolution improvement the self-mixing FMCW radar based on analysis of the spectrum of high-order harmonics of intermediate frequency is proposed. Developed the scheme and investigated the model of Ka-band surveillance self-mixing FMCW radar with digital control and spectral processing of receiving signal. Advantages of this radar are small size, low power consumption and use...
The detection performance of wideband radars in noise is better than that of the narrowband radars under some conditions, due to higher range resolution and less target return fluctuation. The detection probabilities of wideband and narrowband radars for the wideband non-fluctuation, Rayleigh and Ricean target models in white Gaussian noise are deduced. The detection curves show that the wideband...
Inspired by compressed sensing theory, a novel radar system, called hybrid-frequency radar is proposed. It transmits multiple carrier-frequency modulated by random amplitude in each pulse, and can use much fewer pulses than that of stepped-frequency radar to achieve the same non-ambiguous range interval while the target is sparse spatially.
The synthetic aperture technique can not be used to improve azimuth resolution in forward-looking mode or real aperture radar systems. In this paper, an improved High-Frequency-Raised (HFR) algorithm is introduced to enhance the azimuth resolution of radar systems. The super-resolution performance of the proposed algorithm depends on the raise coefficient and is different for different equivalent...
The impact of moving target on the one-dimensional coherent imaging in stepped radar is analyzed in this paper. A cross-correlation-based estimation method of radial velocity is proposed. It is proven by analytical derivation that the cross-correlation analysis on adjacent pulses yields the quantity related to the radial acceleration and velocity of moving target, based on which the radial motion...
Scan rate selection has a crucial impact on the performance of maritime surveillance systems. In this work, a sea clutter database has been used to obtain experimental insight on the trade-off between within-scan and scan-to-scan integration. This paper extends the previous empirical studies to the case of sub-meter range resolution Ka-band coherent sea-clutter data. Results show a clear performance...
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