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An adaptive targets detector used in polarimetric high resolution radars is presented based on generalized likelihood ratio test (GLRT) criterion. The detector can ensure CFAR property for range-distributed targets in compound-Gaussian clutter. The simulation shows that the proposed detector achieves in general a better detection performance than its counterparts.

It is usually not convenient to use the functions supplied by Visual DSP++ to operate peripherals interactively during debug when an emulator is used. In this paper we develop a simple framework which offers a configurable graphic user interface (GUI), a component to manipulate digital signal processor (DSP) memory and a virtual register mechanism. This framework can help DSP developer with modifying peripherals' registers using a user-friendly dialog. Though the framework is developed using Python, a DSP developer who may not be familiar with Python can manipulate it easily.

Most methods of angular estimation for unresolved targets are based on Swerling II targets model. These methods rely upon the use of pulse-to-pulse frequency agility. In this paper we consider the case that the fluctuation of targets observed are slow, research how the RCS fluctuation of targets affects monopulse radar system and then we address a method of resolving two unresolved targets based on the statistical feature of monopulse angular estimation for slow fluctuation targets. The result of simulation demonstrates that this method is effective.

Non-coherent radar backscattering from chaff clouds is studied, employing a polarimetric radar cross section. Two orthogonally polarimetric scattering cross sections are derived. Both mathematical analysis and measurements show that the depolarization phenomenon is remarkable in radar echo of chaff clouds.

Passive centroid jamming is an effective method against conventional monopulse radar. When spatially dispersed decoy is used, the radar antenna will tend to point at the centroid between target and decoy. This paper analyzes the effect of centroid jamming on angle estimation in monopulse radar, and provides for a practical method against this jamming based on multiple targets detection algorithm and a priori knowledge of DOA of the target. Simulation results validate the effectiveness of this method.

The noncoherent processing can alleviate the effect of phase imbalances in receiver channels of monopulse radar. In this paper, a novel noncoherent processing scheme, which uses logarithmic amplifiers, is considered and explicit expressions are derived for the indicated angle as a function of various imbalances in the receiver channels. Its performance is then analyzed using shift in null position and deviation in slope of the angle sensitivity curve as criteria. Its performance in some aspect is superior to that of the conventional monopulse processing due to symmetrical channels and wide dynamic range.

A tri-pole filter is proposed as a video integrator for scanning radar. Coefficients optimization of the tri-pole filter is carried out via genetic algorithm (GA) which evaluates the fitness of individual using a new function in time-domain. The tri-pole filter requires only 0.1 dB increase in signal-to-noise ratio to provide the same detection capability as the optimum integrator. Moreover, it has better stability than two-pole filter because the distance between its poles and unit circle is further. The tri-pole filter is analyzed and it is shown that its performance is superior to that of the two-pole filter.

The measurements of the two-closely spaced targets are merged when the target echoes are not resolved in angle or radial velocity. Conventional monopulse radar will only obtain single DOA measurement of the centroid. The paper provides an approach to extract direction-of-arrival (DOA) of the target. This method is simple and effective, though it requires complex measurements of signal and a priori knowledge of the polarization scattering characteristics of interference.

This paper investigates conventional theory of angular glint based on phase gradient method and considers that it only was expressed as phase distortion of radar echoes, independent of radar antenna parameters. The analysis demonstrates that echo's non-uniform illumination to radar antenna leads to target glint, which causes the distortion of antenna directional diagram at the same time. The paper also regards the distortion of antenna directional diagram as the result of some non-distortional directional diagrams' addition after rotation and weighting, which provides a convenient method to calculate glint error of complicated-target accurately. The simulation results present that the glint error using the new model is more appropriate than using conventional one.

A focused minimum variance distortionless (MVDR) beamformer for broadband adaptive beamforming is formulated and contrasted with the conventional beamformer. The proposed beamformer involves a preprocessor that focuses the signal spaces at different frequencies to a common one and an MVDR beamformer as the narrowband beamformer following the pre-processor. The merits that result as a consequence are improved computational efficiency of focusing and adaptivity and high beamforming resolution of MVDR with short observation times.

The paper focuses on the improved 2-D MUSIC algorithm that operates in beamspace for DOA estimation with a uniform circular array (UCA). The algorithm requires only real eigenvalue decompositions to obtain noise subspace estimates, so that it has many advantages, including reduced amount of computation and enhanced precision, especially in a series of dual coherent sources scenarios. These excellent performances are verified by computer simulations.

Angular glint caused by a target of dual point sources is discussed in phase gradient method. Deterministic relation between phase gradient and RCS is deduced. On the basis of that, a RCS based compensation method of angular glint is presented. The validity is verified by simulation. For target of multi-point sources, compensation for angular glint error is similar if it is treated as a target of dual point sources.