Benefits of space-time diversity for radar - Les bienfaits de la diversité spatio-temporelle en radar

When designing a new radar system, standard resolution trade-offs play a major role, providing the basic parameters of the radar, such as size, update rate, and range. Besides, diversity has long been used for mitigating fading effects due to the fluctuation of targets and clutter. However, with the arrival of more flexible systems, using...

Diversity considerations in wideband radar detection of migrating targets in clutter

Wideband radars have been proposed for detection of moving targets, with unique capability of non-ambiguous detection due to range migration. Moreover, frequency diversity has long been used for mitigating the fading effects caused by target and clutter fluctuations. The real benefits of wideband radars are difficult to analyze, since they...

Adaptive Detection of Range Migrating Target in non-Gaussian Clutter

Adaptive detection of fast moving targets by means of high range resolution radar is considered. It is assumed that a fast-moving target of interest has a few range cells migration during the coherent processing interval and the clutter power fluctuates rapidly along the range. Therefore, the target competes with the clutter responses in a few...

Unambiguous sparse recovery of migrating targets with a robustified Bayesian model

The problem considered is that of estimating unambiguously migrating targets observed with a wideband radar. We extend a previously described sparse Bayesian algorithm to the presence of diffuse clutter and off-grid targets. A hybrid-Gibbs sampler is formulated to jointly estimate the sparse target amplitude vector, the grid mismatch, and the...

Detection of range migrating targets in compound-Gaussian clutter

This paper deals with the problem of coherent radar detection of fast moving targets in a high range resolution mode. In particular, we are focusing on the spiky clutter modeled as a compound Gaussian process with rapidly varying power along range. Additionally, a fast moving target of interest has a few range cells migration within the coherent...

Range migrating target detection in correlated compound-Gaussian clutter

The problem of range-migrating target detection in a compound-Gaussian clutter is studied here. We assume a target to have a range-walk of a few range cells during the coherent processing interval, when observed by wideband radar with high range resolution. Two CFAR detectors are proposed assuming different correlation properties of clutter over...

Performance Prediction of Wideband Unambiguous Target Detection in Diffuse Ground Clutter

In this paper the influence of clutter power spectrum on unambiguous radar target detection with single low pulse repetition frequency wideband waveform is analyzed. Impact of both stationary and diffuse clutter components for different signal bandwidths and coherent processing intervals (CPI) is studied. Exponential model of the ground clutter...

New Sparse-Promoting Prior for the Estimation of a Radar Scene with Weak and Strong Targets

In this paper, we consider the problem of estimating a signal of interest embedded in noise using a sparse signal representation (SSR) approach. This problem is relevant in many radar applications. In particular, estimating a radar scene consisting of targets with wide amplitude range can be challenging since the sidelobes of a strong target can...

Unambiguous Detection of Migrating Targets with Wideband Radar in Gaussian Clutter

In this paper the problem of unambiguous moving target detection using wideband radar is considered. Doppler ambiguities, which are present in the low pulse repetition frequency mode, are transformed into ambiguous sidelobes of targets and clutter using range migration effect. However, the level of these sidelobes is typically high, such that...

Exploiting range migration for unambiguous velocity measurements

One of the most striking challenges that radar designers have to deal with, when developing new doppler systems, is to overcome the difficulty of working with ambiguous velocities. Even using high PRF’s, target’s velocities become ambiguous because wavelengths are getting shorter. This article tries to depict an idea of becoming unambiguous in...

An analytical model for the description of the full-polarimetric sea surface Doppler signature

This paper describes an analytical model of the full-polarimetric sea surface scattering and Doppler signature. The model combines the small-slope-approximation theory (at the second order) with a weak nonlinear sea surface representation. Such a model is used to examine the variation of the Doppler central frequency/bandwidth and of the...

Fast implementation of iterative adaptive approach for wideband unambiguous radar detection

Iterative adaptive approach for unambiguous wideband radar target detection

DopSCAT: A mission concept for simultaneous measurements of marine winds and surface currents

A radar scatterometer operates by transmitting a pulse of microwave energy toward the ocean’s surface and measuring the normalized (per-unit-surface) radar backscatter coefficient (r8). The primary application of scatterometry is the measurement of near-surface ocean winds. By combining r 8 measurements from different azimuth angles, the 10 m...

Self-similarity matrix based slow-time feature extraction for human target in high-resolution radar

A new approach is proposed to extract the slow-time feature of human motion in high-resolution radars. The approach is based on the self-similarity matrix (SSM) of the radar signals. The Mutual Information is used as a measure of similarity. The SSMs of different radar signals (high-resolution range profile, micro-Doppler, and range-Doppler...

Space-Time radar waveforms: Circulating codes

This paper describes a concept of the circulating codes covering the whole class of the space-time codes. The circulating codes do not narrow the radiated pattern of the antenna array, thus providing a wide angular coverage, possibly tunable. In turn, the beam-forming on transmit is achievable by means of the signal processing in one (or each)...

Clutter suppression for moving targets detection with wideband radar

Wideband (high range resolution) radars have been proposed [7] as high performance systems for detection of small targets in adverse environments, due to their small resolution cells and non-ambiguity in range and velocity (velocity ambiguity removed by the measurement of the range migration of the target during the pulse train duration)....