آشكارسازي با نرخ ثابت هشدار كاذب در رادارهاي MIMO

چكيده انگليسي :

AbstractConstant False Alarm Rate CFAR detection is an important concept in radar detectionproblems CFAR processors are useful for detecting radar targets in background for whichsome parameters of the statistical distribution are not known and may be non stationary The conventional method for producing CFAR property in radar is to set the detectionthreshold adaptively and equal to the scaled version of the noise power estimated byprocessing the resolution cells surrounding the cell under test to achieve the desiredconstant false alarm probability Various algorithms have been proposed to keep the falsealarm rate constant in different environmental conditions such as the presence ofinterfering targets or clutter edge These algorithms can be divided into single pulse CFARdetectors one dimensional CFARs and multiple pulse CFAR detectors two dimensionalCFARs Multiple pulse CFAR detectors are detectors that use the samples of multiplepulses in each range cell for target detection A conventional processing method in thesedetectors is to integrate the pulses incoherently and apply the one dimensional CFARdetector to the result Although CFAR detection has been studied widely for monostaticradars reviewing the publications in this field shows that it has not been consideredseriously for MIMO radars MIMO radar is defined broadly as a radar employing multipletransmitters and receivers and capable of jointly processing signals received at multiplereceive antennas MIMO radar may be configured with its antennas collocated or widelyseparated over an area In this thesis CFAR detection for MIMO radars with widelyseparated antennas in Gaussian noise is considered After modeling the received data in asingle pulse MIMO radar with widely separated antennas some of the one dimensionalCFAR detectors from Averaging and Ordered statistics families have been generalized inseveral ways for MIMO radars Some of these methods are similar to those employed togeneralize one dimensional CFAR detectors for processing multiple pulses in monostaticradars Parameters of these generalized detectors have been found using mathematicalanalysis Also performance of these detectors has been evaluated by means of detectionand false alarm probability calculation in homogeneous background and computersimulation results in nonhomogeneous background Comparison of different detectors performances shows that two dimensional CFAR detectors used for processing multiplepulses in monostatic radars are not perfect for MIMO radars Instead the algorithms thatestimate the total noise power by averaging the noise power estimations in MIMO radar sdifferent receivers have a better performance in most of the cases In addition it has beenshown that proposed detectors which are generalization of ordered statistics processors aremore robust than the others in multiple target situations

جنتيان، نفيسه

آشكارسازي با نرخ ثابت هشدار كاذب در رادارهاي MIMO

آشكارسازي CFAR