Principles of Modern Radar - Volume 2 1891121537

Automatic Target RecognitionCHAPTER14Kristin F. Bing, Lisa M. Ehrman, Teresa M. Selee✬Chapter Outline14.1 Introduction .................................................................. 63114.2 Unified Framework for ATR ................................................... 63314.3 Metrics and Performance Prediction .......................................... 63414.4 Synthetic Aperture Radar ..................................................... 63814.5 Inverse Synthetic Aperture Radar ............................................. 65214.6 Passive Radar ATR ........................................................... 65614.7 High-Resolution Range Profiles............................................... 65814.8 Summary..................................................................... 66114.9 Further Reading .............................................................. 66114.10 References ................................................................... 66214.11 Problems..................................................................... 668✫✩✪14.1 INTRODUCTIONThe three main functions of radar are detection, tracking, and target recognition. Detectionis discussed at length in Principles of Modern Radar: Basic Principles, and tracking isaddressed in Chapter 15 of this text. This chapter focuses on target recognition.Automatic target recognition (ATR) systems are deployed in a broad spectrum of military,civilian, and commercial applications, where they assist with everything from identifyingaircraft [100–105] to spotting tornados [106] to countering bioterrorism [107–109].Regardless of the application, the goal is the same. ATR systems attempt to automaticallycategorize targets into one of a set of classes. The sensors exploited in ATR systems are asvaried as the applications. These include imaging sensors such as synthetic aperture radar(SAR), inverse synthetic aperture radar (ISAR), and electro-optical/infrared (EO/IR) focalplane arrays, as well as non-imaging sensors such as high range resolution (HRR) radar,bistatic passive radar, and Raman spectrometers [107–109].Before progressing any further, it is worth noting that the terminology varies substantiallyfrom one radar application to another. For example, literature on SAR and ISARtypically use discrimination to refer to the process of segmenting an image into the broadclasses of (natural) background and man-made portions. The subsequent process of assigninga target to a specific category of interest is then referred to as classification. However,631