Other SAR type radars have been built for recon- 

 naissance and terrain- imaging from aircraft such as the AN/APQ-102. 

 Optical processing techniques on the radar data produce images having 

 the appearance of optical quality. Reference 5 provides a good summary 

 of the state of SAR technology. 



(2) Surveillance Coverage Capabilities 



Conventional Radars --The area coverage of a conven- 

 tional surveillance radar depends on the maximum altitude at which it 



can still detect the required target. For example, TI analysis of their 



2 

 proposed modified AN/APS-116 has shown that it could detect our 500-m 



fishing vessel target out to 300 nmi. The aircraft platform altitude 



that will support this radar horizon distance is around 70 kft. The 



aircraft platform could be either a manned aircraft or remotely piloted 



vehicle (RPV). Assuming the maximum useful coverage is 200 nmi, an 



aircraft could fly along the coastline and search only the seaward sector. 



This surveillance geometry is seen in Figure 4. 



The area covered in a radar sweep included by the 



radar maximum range and the 200-nmi boundary is approximately 104,000 



2 

 nmi . Considering an eight hour mission period and an aircraft velocity 



of 250 kts, the total coast length passed over would be 8 x 250 = 2000 nmi. 



2 

 Considering this to be a 200-nmi swath, over 400,000 nmi could be sur- 

 veyed per eight-hour mission. Restating this, a single aircraft could 

 patrol the west coast out to and beyond the 200-nmi limit every four 

 hours. This average rate applies to detection of potential fishing 

 vessels only. Classification to sort out actual foreign fishing vessels 

 would require additional resources. 



Synthetic Aperture Radars (SARS)--The coverage from 

 a synthetic aperture radar is usually limited by the swath width it can 



43 



