CHAPTER 11

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CHAPTER 11RADAR CROSS SECTIONEugene F. KnottThe Boeing INTRODUCTIONA radar detects or tracks a target, and sometimes can identify it, only becausethere is an echo signal. It is therefore critical in the design and operation of radarsto be able to quantify or otherwise describe the echo, especially in terms of suchtarget characteristics as size, shape, and orientation. For that purpose the targetis ascribed an effective area called the radar cross section. It is the projected areaof a metal sphere which would return the same echo signal as the target had thesphere been substituted for the the echo of the sphere, however, which is independent of the viewingangle, the echoes of all but the simplest targets vary significantly with orienta-tion. As such, one must mentally allow the size of this fictitious sphere to vary asthe aspect angle of the target changes. As will be shown, the variation can bequite rapid, especially for targets many wavelengths in echo characteristics depend in strong measure on the size and nature ofthe target surfaces exposed to the radar beam.

the wave equation are, at best, guidelines for gauging other (approximate) meth-ods of computing scattered fields. An alternative approach is the solution of the integral equations governing the

  Chapter, Equations, Waves, Chapter 11, Wave equation