Page 459 - Fundamentals of Radar Signal Processing
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(6.33)

               Thus, under hypothesis H ,                       . Similarly, under hypothesis H  y = m
                                             0
                                                                                                     1
               + w and                   . Note that the mean of z is real in both cases. The power
               of  the  complex  Gaussian  noise  splits  evenly  between  the  real  and  imaginary
                                                  H
               parts  of z.  Since  ϒ  =  Re{m y},  it  follows  that                         under H   and
                                                                                                       0
                                under H . Following the procedure used in Sec. 6.1.2, it can be
                                          1
               seen that







                                                                                                       (6.34)

               Repeating  the  development  of Eqs.  (6.22)  to (6.24)  gives  the  probability  of
               detection













                                                                                                       (6.35)

               Note again that the last term in Eq. (6.35) is the square root of the energy in the

               signal m,  divided  this  time  by  the  noise  power            ,  i.e.,  the  signal-to-noise
               ratio. Thus Eq. (6.35) can be written as










                                                                                                       (6.36)


               Finally, in the equal means case when m = m1 , Eq. (6.35) is similar (but not
                                                                        N
               identical)       to Eq.  (6.24).  The  coherent  case  includes  the  term
                                                because all of the signal energy competes with only
               half of the noise power.

                     Figure 6.5 shows the receiver operating characteristic for this example. It
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