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FIGURE 6.10   Taxonomy of detection problems considered. (Adapted from
               Levanon, 1988.)



               Each of these will be discussed in turn in this section, with the exception of the
               Swerling 3 and 4 cases, for which the strategy is shown but the details are not
               carried out; the partially correlated case, which is not considered; and adaptive
               threshold-setting techniques (CFAR), which are the subject of Sec. 6.5.


               6.3.1   Coherent, Noncoherent, and Binary Integration
               The ability to detect targets is inhibited by the presence of noise and clutter.
               Both are modeled as random processes; the noise as uncorrelated from sample

               to sample, the clutter as partially correlated (including possibly uncorrelated)
               from sample to sample. The target is modeled as either nonfluctuating (i.e., a
               constant)  or  a  random  process  that  can  be  either  completely  correlated  or
               completely  uncorrelated  from  sample  to  sample  (the  Swerling  models),  or
               partially  correlated  from  sample  to  sample.  The  signal-to-interference  ratio

               (SIR)  and  thus  the  detection  performance  are  often  improved  by integrating
               (adding) multiple samples of the target and interference, motivated by the idea
               that the interference can be “averaged out” by adding multiple samples. This
               idea was first discussed in Chap. 1. Thus, in general detection will be based on
               N samples of the target + interference. Note that care must be taken to integrate
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