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Millimeter Wave RADAR Power-Range Spectra Interpretation    81

                                                    PDFs for noise and signal + noise
                                      1400
                                                   Signal + noise distribution
                                      1200

                                      1000

                                     Number  800       Noise distribution

                                       600

                                       400

                                       200

                                        0
                                         –15  –10  –5   0    5   10   15   20   25   30
                                                            Power (dB)

                              FIGURE 2.21 Experimental estimation of signal and noise distributions. In the CFAR
                              method, the local noise-plus-clutter power (Equation [2.10]) in the window is used to
                              set the detection threshold. The method compares the signal in the test window and
                              the detection threshold. The method fails when there are multiple detections within a
                              range-bin and in cluttered environments.


                              u(k) =[v(k), α(k)]. v(k) is the velocity of the vehicle at time k and α(k) is the
                              steering angle. In full, the predicted state at time, (k + 1) becomes

                                             ˆ x(k + 1|k)     ˆ x(k|k)    x(k)
                                          ⎡            ⎤   ⎡        ⎤   ⎡     ⎤
                                          ⎢  ˆ y(k + 1|k)  ⎥  ⎢  ˆ y(k|k)  ⎥  ⎢  y(k) ⎥
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                             ˆ               ˆ
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                          ⎢ θ R (k + 1|k) ⎥  ⎢ θ R (k|k) ⎥  ⎢ α(k) ⎥
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                               (k + 1|k) ⎥     (k|k) ⎥
                                          ⎢ x p 1          ⎢ x p 1      ⎢ 0 p 1  ⎥
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                            y (k + 1|k)      y (k|k)
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                          ⎢ p 1        ⎥   ⎢ p 1    ⎥   ⎢  0 p 1 ⎥
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                          ⎢ϒ R 1  (k + 1|k)⎥  ⎢ϒ R 1  (k|k)⎥  ⎢ 0 p 1 ⎥
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                                                                       (2.24)
                                               (k + 1|k) ⎥     (k|k) ⎥
                                          ⎢ ϒ a 1          ⎢ ϒ a 1      ⎢ 0 p 1  ⎥
                                          ⎢            ⎥ = ⎢        ⎥ + ⎢     ⎥
                                                 .              .          .
                                          ⎢      .     ⎥   ⎢    .   ⎥   ⎢  .  ⎥
                                                 .              .          .
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                          ⎢ x p N  (k + 1|k) ⎥  ⎢ x p N  (k|k) ⎥  ⎢ 0 p N  ⎥
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                               (k + 1|k)       (k|k)
                                          ⎢            ⎥   ⎢        ⎥         ⎥
                                            y p N           y p N       ⎢ 0 p N ⎥
                                          ⎢            ⎥   ⎢        ⎥   ⎢
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                          ⎢ ϒ R N  (k + 1|k) ⎥  ⎢ ϒ R N  (k|k) ⎥  ⎢  0 p N ⎥
                                          ⎢            ⎥   ⎢        ⎥   ⎢     ⎥
                                          ⎣ϒ a N  (k + 1|k)⎦  ⎣ϒ a N  (k|k)⎦  ⎣ 0 p N ⎦
                                             L(k + 1|k)      L(k|k)        0
                              © 2006 by Taylor & Francis Group, LLC
                                 FRANKL: “dk6033_c002” — 2006/3/31 — 17:29 — page 81 — #41
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