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Radar systems operating in a maritime environment need to be able to detect targets against a background of sea clutter returns. Hence it is important to understand the statistical behaviour of these returns in order to optimise a radar system detection algorithm. In this paper low and medium grazing angle radar sea clutter are analysed, to separate the effects of wind driven sea and swell in the ...Show More
Low grazing angle S-band radar sea clutter data, collected with the NetRAD multistatic radar system, are analyzed. The Suzuki distribution, a compound Gaussian model with log normal texture, is found to be a good model for both monostatic and bistatic clutter. Clutter textures from simultaneously recorded monostatic and bistatic data are interpreted using hydrodynamics, providing estimates of the ...Show More
Two examples of low grazing angle radar sea clutter, both well-described by the compound $K$ -distribution model, are studied. Pulse Doppler processing is applied to obtain 2-D range–time textures for the intensity, centroid, and width of the Doppler spectrum. The first example exhibits a monochromatic swell pattern, allowing phase averaging to be applied to the textures. The second example has a...Show More
Modelling and simulation of radar sea clutter is extremely important to assist with radar system design, evaluate radar detection algorithms and stimulate radar processors during development and testing. In this paper, the key tradeoffs in designing a scanning maritime radar are presented with details of how the radar return can be simulated. The sea clutter model is a compound Gaussian model with...Show More
The trimodal discrete (3MD) radar clutter model is a simple and accurate model for the interference distribution, which facilitates the computation of the probability of false alarm as a function of the detection threshold. Four estimation methods for the 3MD parameters are presented: two method-of-moments estimators-one based on an analytic solution to the moment equations for integer order from ...Show More
This paper presents a novel implementation of the saddle-point technique for calculating the non-coherent detection probability of targets by airborne surveillance radar in the presence of pulse-to-pulse correlation. It is based on the inverse Laplace transform of the moment generating function for the returned power distribution by means of integration along the path of steepest descent. To illus...Show More
A new two component compound Gaussian model is proposed for coherent radar sea clutter, with each component having its own spatial correlation. One component represents Bragg scattering from capillary waves, modulated in both frequency and intensity by gravity waves, and the other fast scattering from breaking waves. The intensity of each component is represented by an independent gamma variate wi...Show More
Modelling and simulation of radar sea-clutter is extremely important for evaluating radar detection algorithms and to stimulate radar processors during development and testing. Of the many aspects of sea-clutter, the Doppler spectrum plays a key role in determining the statistics which are important for coherent processing. In this paper, the evolving Doppler spectrum model and the spatially and t...Show More
Robustly predicting target detection performance in temporally correlated clutter has proven to be a difficult problem. If the correlation is not accounted for in a radar model, the required signal to interference ratio for a given probability of detection will be incorrect, resulting in over-estimated performance. In this paper, we examine exact and approximate methods for calculating the probabi...Show More
This paper describes the non-coherent target detection performance of an airborne surface surveillance radar in the presence of medium grazing angle sea clutter. In the absence of frequency agility, the temporal correlation of the sea clutter can be significant and if it is not accounted for in the clutter model, the required signal to interference ratio for a given probability of detection will b...Show More
Accurate simulation of sea-clutter is essential to assess the performance of existing target detection schemes and to assist in the development of new ones. A recent simulation technique which captures the evolving Doppler spectrum has been demonstrated in a number of recent publications for both low and high grazing angle data sets. This paper presents empirical models for each of the parameters ...Show More
Robust maritime surveillance with radar requires an accurate description of the backscatter from the sea. The probability distribution of the backscatter is commonly used to determine the threshold for separating targets from clutter. Analysis of data collected at medium grazing angles, between 15° and 45°, by the Defence Science Technology Organisation (DSTO) Ingara fully polarimetric X-band rada...Show More
A method for simulating coherent sea clutter has been adapted for Pareto distributed clutter by using an inverse gamma distribution for the local clutter intensity. The model is applied to the range variation of Doppler spectra from Pareto distributed clutter collected at grazing angles of 31°-37° with the DSTO Ingara radar. The model produces Doppler spectra with a Gaussian shape that vary with r...Show More
The probability distribution of the radar backscatter is commonly used to determine the threshold for separating targets from clutter. Analysis of sea-clutter data collected at high grazing angles, between 15° and 45°, by the Defence Science Technology Organisation (DSTO) Ingara fully polarimetric X-band radar has been used extensively to test distribution models given a large number of samples. T...Show More
Robust maritime surveillance with radar requires an accurate description of the backscatter from the sea. The probability distribution of the backscatter is commonly used to determine the threshold for separating targets from clutter. Analysis of data collected at high grazing angles, 15° and 45° by the Defence Science Technology Organisation (DSTO) Ingara fully polarimetric X-band radar has shown...Show More
Robustly predicting target detection performance in temporally correlated clutter with a fluctuating target has proven to be a difficult problem. If the correlation is not accounted for in a radar model, the required signal to interference ratio for a given probability of detection, Pd, could be incorrect by several dB, resulting in over-estimated performance. This paper describes a robust method ...Show More
The memoryless nonlinear transformation method is used to simulate Pareto distributed sea clutter with a specified correlation function for the clutter power. The Pareto distribution is formed from a compound model with a negative exponential distribution for the speckle intensity and an inverse gamma distribution for the clutter power. An estimator based on the expectation value of z log z is obt...Show More