B. L. CORDRY • W. R. FRIED 

 R. H. LAPRADE • F. STAUFFER 



CHAPTER 14 



AIRBORNE NAVIGATION AND GROUND 

 SURVEILLANCE RADAR SYSTEMS* 



The preceding pages have concentrated on airborne radar systems which 

 are employed for the detection, acquisition, and tracking of airborne targets 

 (AI and AEW radars). For such systems, the operation of the radars had 

 to be made as independent as possible of the degrading effects of weather, 

 ground return, and sea return. 



An equally important group of radar systems is composed of systems 

 for which the radar returns from the ground, sea, and meteorological 

 phenomena constitute the desired intelligence. Such systems are employed 

 for navigation, bombing, and reconnaissance, as was briefly described in 

 Chapter 1. 



While the same basic laws of nature apply to these systems, there are 

 sufficient diff"erences in their importance relative to tactical requirements — 

 as reflected by the design practices necessary to achieve the navigation 

 and mapping function — to warrant a separate discussion of these radar 

 system types. This chapter will discuss the essential features of the 

 airborne radar systems designed to provide navigation and ground mapping 

 intelligence. Particular emphasis will be given to the interrelations among 

 radar techniques and the tactical functions. This information will provide 

 the reader with the background knowledge necessary to derive the technical 

 specifications for such systems, as was done for the AI and AEW systems 

 in Chapter 2. The primary technical problems and limiting considerations 

 of each type of system will be outlined. Examples of operational installa- 

 tions will be presented to acquaint the reader with the state of the art. 



The discussion will cover the following radar system types: 



1. Doppler navigation systems 



2. Weather radar systems 



♦Paragraphs 14-1 through 14-8 are by W. R. Fried. Paragraphs 14-9 through 14-14 are by 

 B. L. Cordry. Paragraphs 14-15 through 14-21 are by R. H. Laprade. Paragraphs 14-22 

 through 14-26 are by F. Stauffer. 



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