Introduction 



Following the RMS 

 TITANIC's disastrous collision 

 with an iceberg off the Tail of 

 the Grand Banks of 

 Newfoundland in 1912, the 

 U.S. Coast Guard has been 

 charged with the conduct and 

 administration of the North 

 Atlantic Ice Patrol. The 

 ongoing exploitation of remote 

 sensing techniques, starting 

 with shipboard radar and 

 progressing to airborne radar, 

 has enabled the International 

 Ice Patrol to safely discharge 

 its duties for over 85 years. 

 The International Ice Patrol 

 (IIP) currently uses a suite of 

 airborne radars, visual 

 reconnaissance, data from 

 Canadian government sources 

 and observations by 



transatlantic ships to record, 

 track and report the locations of icebergs in 

 the vicinity of the Grand Banks of 

 Newfoundland (Figure 1). IIP performs 

 aerial remote sensing reconnaissance on 

 board a Coast Guard Hercules (HC-130), a 

 four engine turboprop aircraft, equipped 

 with a Motorola AN/APS-135 Side Looking 

 Airborne Radar (SLAR) and a Texas 

 Instruments AN/APS-137 Forward Looking 

 Airborne Radar (FLAR). Though both are 

 X-band radars, SLAR is a real aperture 

 radar which provides a thermal film analog 

 output. The newer FLAR displays on a 

 seven-inch digital screen and features an 

 Inverse Synthetic Aperture (ISAR) mode, 

 allowing the user to identify targets based 

 on doppler characteristics. IIP has 

 operated using this dual-sensor mode 

 effectively since 1991. (CMP, 1994) 



In November 1995, a Mission 

 Analysis was conducted to investigate IIP 

 operations and to identify its major costs 



Figure 1. IIP Operations Area on Grand Banks. Location of Hibernia 

 GBS shown by "H", location of TITANIC sinking shown by T. 



and opportunities for future improvements 

 (Pritchett and Armacost, 1995). This report 

 stated that as satellite Synthetic Aperture 

 Radar (SAR) assets become more 

 prevalent and tested, IIP should investigate 

 SAR products as additional means of 

 conducting ice reconnaissance. It is 

 speculated that as SAR costs decrease, 

 satellite remote sensing products may 

 alleviate the major cost to IIP of aircraft 

 operation and help obviate the accelerating 

 obsolescence of the AN/APS-135 SLAR 

 (Sielbeck et al., 1998). Over the past five 

 years, much work has been done to 

 assess the abilities of satellite SAR with 

 respect to point target detection (Vachon et 

 al., 1997; Olsen et al., 1995), though 

 admittedly and understandably, most of 

 this work has been devoted to the 

 detection and identification of surface 

 vessels or natural oceanic phenomena. 

 Some researchers, however, have focused 



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