Moving target indication

About: Moving target indication is a research topic. Over the lifetime, 2653 publications have been published within this topic receiving 32435 citations.

Multi-channel moving target radar detection and imaging apparatus and method

Abstract: A radar detection and imaging system provides for the simultaneous imaging of the stationary objects on the earth's surface and the detection and imaging of moving targets. The radar system includes at least one transmitting aperture and a plurality of receiving apertures that are simultaneously operated in a synthetic aperture radar (SAR) mode caused by the motion of the satellite or airborne platform on which they are mounted. Each receiving aperture is connected to its own coherent receiver and the digitized signals from all receivers are processed to image both stationary clutter and moving targets. The system employs space- time adaptive processing (STAP) algorithms to better compensate for channel mismatches, better suppress stationary clutter, and to suppress mainbeam jamming. Moving target detection and estimation modules are also included and are their performance is improved as a result of the STAP algorithms. The system also employs SAR processing algorithms to create high- resolution images of stationary objects, and to image moving targets. The SAR and STAP algorithms are uniquely integrated in the radar signal processor (RSP) to provide improved performance while reducing the computational requirements, facilitating real-time implementation.

An airborne synthetic aperture radar (SAR) experiment to support RADARSAT-2 ground moving target indication (GMTI)

Abstract: As part of the preparatory work for the RADARSAT-2 moving object detection experiment (MODEX special operating mode), an airborne experiment was conducted at Canadian Forces Base Petawawa in July 1999 to study synthetic aperture radar (SAR) along-track interferometry (ATI) and SAR displaced phase centre antenna (DPCA) as candidate measurement techniques. The CV 580 SAR system operated by Environment Canada was configured as a two-aperture temporal interferometer, and data were collected over an experiment site that contained coordinated, global positioning system (GPS) monitored, moving targets. A robust ATI phase probability density function was identified and used in conjunction with a moving-target matched filter to extract and measure target motion. Corner reflector and vehicle velocities were measured for target speeds between 9 and 100 km/h to within 5% accuracy. SAR ATI and SAR DPCA performed equally well over this range of velocities, but ATI appears to be the more robust processing algorithm.

A variable structure multiple model particle filter for GMTI tracking

Abstract: The problem of tracking ground targets with GMTI sensors has received some attention in the recent past. In addition to standard GMTI sensor measurements, one is interested in using non-standard information such as road maps, and terrain-related visibility conditions to enhance tracker performance. The conventional approach to this problem has been to use the variable structure IMM (VS-IMM), which uses the concept of directional process noise to model motion along particular roads. In this paper, we present a particle filter based approach to this problem which we call variable structure multiple model particle filter (VS-MMPF). Simulation results show that the performance of the VS-MMPF is much superior to that of VS-IMM.

High-speed multi-target detection with narrowband radar

Abstract: High-speed multi-target detection is a challenging problem in radar applications. Typically, targets with high speed go through several range cells in the observation period, which makes it more difficult to obtain each target's power coherently accumulated for target detection. In this study, novel multi-target detection with a narrowband radar system is proposed. In order to remove range migration and obtain coherent integration of the target energy, the Keystone transform is applied to the moving targets. However, because of the high target velocity and the low radar pulse repetition frequency phase ambiguity will occur, so the range migration will not be corrected properly. Then the phase ambiguity function of the kth target is compensated, and the envelope of the kth target concentrates in a certain range cell. Following by frequency modulation rate search a quadratic phase term is compensated, and the signal energy is finally coherently accumulated by FT analysis. The target is detected if the ratio of peak value to noise is higher than a predetermined threshold. For target detection in low signal-to-noise ratio (SNR), the Clean technique is applied. The proposed algorithm is verified by simulation and raw radar data results.

A comparison of displaced phase centre antenna and along-track interferometry techniques for RADARSAT-2 ground moving target indication

Abstract: Canada's RADARSAT-2 commercial synthetic aperture radar (SAR) satellite will have an experimental mode that will permit ground moving target indication (GMTI) measurements to be made. In this mode of operation, the radar antenna is partitioned into two subapertures that sequentially observe the scene of interest from the same point in space. Two of the GMTI processing approaches currently being explored are examined in this paper. One utilizes the displaced phase centre antenna (DPCA) clutter-cancellation technique to provide subclutter visibility for dim, slowly moving objects. The other is based on the along-track interferometry (ATI) technique, in which magnitude and phase information of the targets' interferograms are exploited to extract them from the background clutter. In this paper the performance of each processor is examined for three RADARSAT-2 slant-range resolutions: 12.5, 3.0, and 1.5 m. The study focuses on the influence of SAR resolution cell size on the GMTI processor performance. Results...