Coherent and non-coherent processing of multiband radar sensor data

[摘要] Increasing resolution is an attractive goal for all types of radar sensorapplications. Obtaining high radar resolution is strongly related to thesignal bandwidth which can be used. The currently available frequency bandshowever, restrict the available bandwidth and consequently the achievablerange resolution. As nowadays more sensors become available e.g. onautomotive platforms, methods of combining sensor information stemming fromsensors operating in different and not necessarily overlapping frequency bandsare of concern. It will be shown that it is possible to derive benefit fromperceiving the same radar scenery with two or more sensors in distinctfrequency bands. Beyond ordinary sensor fusion methods, radar information canbe combined more effectively if one compensates for the lack of mutualcoherence, thus taking advantage of phase information.

At high frequencies, complex scatterers can be approximately modeled as agroup of single scattering centers with constant delay and slowly varyingamplitude, i.e. a set of complex exponentials buried in noise. Theeigenanalysis algorithms are well known for their capability to better resolvecomplex exponentials as compared to the classical spectral analysis methods.These methods exploit the statistical properties of those signals to estimatetheir frequencies. Here, two main approaches to extend the statisticalanalysis for the case of data collected at two different subbands arepresented. One method relies on the use of the band gap information (andtherefore, coherent data collection is needed) and achieves an increasedresolution capability compared with the single-band case. On the other hand,the second approach does not use the band gap information and represents arobust way to process radar data collected with incoherent sensors. Combiningthe information obtained with these two approaches a robust estimator of thetarget locations with increased resolution can be built.

[学科分类] 电子、光学、磁材料