Page 163 - ITU Journal Future and evolving technologies – Volume 2 (2021), Issue 2
P. 163

ITU Journal on Future and Evolving Technologies, Volume 2 (2021), Issue 2




                3                                              0.14
                                              Multi-rotor UAVs                                Multi-rotor UAVs
                                              Helicopters                                     Helicopters
               2.5                            Fixed wing UAVs   0.12                          Fixed wing UAVs
                                              Small fixed wing planes                         Small fixed wing planes
                                              Large fixed wing planes                         Large fixed wing planes
                2                             Fighter jets     0.1                            Fighter jets
                                              Cruise missiles  0.08                           Cruise missiles
               PDF  1.5                       Birds           PDF                             Birds
                                              Ballistic missiles
                                                                                              Ballistic missiles
                                              Rockets & artillery
                                              HGVs             0.06                           Rockets & artillery
                                                                                              HGVs
                1
                                                               0.04
               0.5
                                                               0.02
                0                                                0
                 0    10   20   30   40    50   60   70   80     0   1000  2000  3000  4000  5000  6000  7000  8000
                              Length of central part (m)                        Max. velocity (m/s)
                                    (a)                                             (b)
                               Fig. 8 – PDFs of length of central section and maximum velocity of the training targets.

          Algorithm 2 Simultaneous Detection, Classi ication, Localization, and Tracking of the Aerial Target.
          1: procedure SDCLT
          2: % The total coverage of a single virtual door is   Δ  ℎ and the total area spanned at all the steering positions is   Δ  Δ  (2   +1)  ℎ
                                                  th
          3: % Considering that we have    laser mesh at the    steering position (see Fig. 3 )
          4:   for i = ‑N:N do
          5:      if there are laser beams with   /   <    then for a given pfa
                                            G
          6:         Obtain the estimated features of the target given in Table 1, (and discussed in Section 4)
          7:         Categories and classify the target (see Section 5)
          8:         if a positive threat identi ied then
                                                                             th
          9:           Obtain the localization and tracking of the target and update at every    steering position (see Section 5.2)
          10:        end if
          11:     else
          12:        Steering positions only
          13:     end if
          14:  end for
          15: return Estimated coordinates, and features of the target (if detected)
          16: end procedure


         Each class has    number of samples and there are    = 11  Let C (Tr)    represents an array that  contains the target







         classes in our training set.                          classes. In (14), the size of this vector corresponding to
         Similar to the training data, the feature values for a given  (11) are    ×   , given as
         target is given in the form of a matrix, M (eval)  as
                                                                         [   1,1     1,2  …    1,       2,1     2,2  …
                                                                   (Tr)
                        (c)     (c)  ℎ (c)     (w)     (w)     (t)  C  =              … …            …     ]   
                                          1
                           1
                      1
                                1
                                     1
                                               1
                    ⎡ (c)  (c)  (c)  (w)  (w)  (t)                                2,          ,1    ,2    ,  
                       
                    ⎢ 2      2  ℎ 2     2     2     2                                                       (14)
                    ⎢ ⋮    ⋮    ⋮    ⋯    ⋮    ⋮               where    is the transpose operation.
                      (c)  (c)  (c)  (w)  (w)  (t)
                                                 
                                       
                                  
                        
                             
                                            
            M (eval)  =  ⎣   ′     ′  ℎ ′     ′     ′     ′  (12)







                               (t)     1     1     1  ℎ (G)    In this study, four different types of   iers, i.e.,

                                                1
                              1
                               (t)     2     2     2  ℎ (G) ⎤  Naive Bayes (NB, Linear Discriminant Analysis (LDA, K‑
                                                2 ⎥
                              2







                              ⋮   ⋮    ⋮    ⋮    ⋮ ⎥           nearest Neighbor (KNN, and Random Forest (RF, are
                              (t)               (G)            used for classi ication. With    representing the modeling
                                    
                               ′     ′     ′     ′  ℎ ′ ⎦
                                              
                                         
                                                               function of a classi ier, ℳ , ℳ , ℳ , and ℳ expresses

                                                                                                     4
                                                                                     1
                                                                                         2
                                                                                             3
                                                               the corresponding models as given below
                                                    ′
          where the number of samples for the target are    . The
          target data is interpolated to adjust the size of the target’s
          data equal to the training data that can be formulated as
                    M (eval)  =interpolate(M (eval) ,   ).  (13)
                                             © International Telecommunication Union, 2021                   149
   158   159   160   161   162   163   164   165   166   167   168