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current

Current distribution on metal or dielectric antenna or array surface

Syntax

current(object,frequency)
i = current(object,frequency)
current(object,frequency,'dielectric')
i = current(object,frequency,'dielectric')

Description

example

current(object,frequency) calculates and plots the absolute value of the current on the surface of an antenna or array object, at a specified frequency.

example

i = current(object,frequency) returns the x, y, z components of the current on the surface of an antenna or array object, at a specified frequency.

example

current(object,frequency,'dielectric') calculates and plots the absolute value of current at a specified frequency value on the dielectric face of the antenna or array.

i = current(object,frequency,'dielectric') returns the x, y, z components of the current on the dielectric surface of an antenna or array object, at a specified frequency.

Examples

collapse all

Calculate and plot the current distribution for a circular loop antenna at 70MHz frequency.

 h = loopCircular;
 current(h,70e6);

Calculate the current distribution of a default rectangular array at 70MHz frequency.

h = rectangularArray;
i = current(h,70e6)
i = 
  Columns 1 through 4

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0039 + 0.0063i  -0.0018 - 0.0027i   0.0018 + 0.0031i  -0.0018 - 0.0029i
   0.0041 + 0.0067i   0.0160 + 0.0258i   0.0197 + 0.0320i   0.0274 + 0.0448i

  Columns 5 through 8

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0016 + 0.0028i  -0.0016 - 0.0027i   0.0014 + 0.0026i  -0.0014 - 0.0025i
   0.0310 + 0.0508i   0.0377 + 0.0624i   0.0409 + 0.0680i   0.0468 + 0.0787i

  Columns 9 through 12

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0012 + 0.0023i  -0.0012 - 0.0022i   0.0009 + 0.0021i  -0.0010 - 0.0020i
   0.0495 + 0.0837i   0.0546 + 0.0934i   0.0569 + 0.0980i   0.0610 + 0.1065i

  Columns 13 through 16

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0007 + 0.0018i  -0.0008 - 0.0017i   0.0005 + 0.0015i  -0.0006 - 0.0014i
   0.0628 + 0.1105i   0.0660 + 0.1180i   0.0673 + 0.1214i   0.0695 + 0.1277i

  Columns 17 through 20

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0002 + 0.0014i  -0.0003 - 0.0012i   0.0000 + 0.0012i  -0.0001 - 0.0067i
   0.0703 + 0.1306i   0.0713 + 0.1361i   0.0716 + 0.1380i   0.0717 + 0.1464i

  Columns 21 through 24

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0001 - 0.0068i   0.0000 + 0.0012i  -0.0003 - 0.0012i   0.0002 + 0.0014i
   0.0717 + 0.1463i   0.0716 + 0.1380i   0.0713 + 0.1361i   0.0703 + 0.1306i

  Columns 25 through 28

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0005 - 0.0015i   0.0005 + 0.0015i  -0.0008 - 0.0018i   0.0007 + 0.0017i
   0.0695 + 0.1276i   0.0673 + 0.1214i   0.0660 + 0.1179i   0.0628 + 0.1105i

  Columns 29 through 32

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0010 - 0.0021i   0.0010 + 0.0020i  -0.0012 - 0.0023i   0.0012 + 0.0022i
   0.0610 + 0.1065i   0.0568 + 0.0979i   0.0546 + 0.0934i   0.0495 + 0.0837i

  Columns 33 through 36

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0014 - 0.0026i   0.0014 + 0.0025i  -0.0016 - 0.0028i   0.0016 + 0.0027i
   0.0467 + 0.0786i   0.0408 + 0.0679i   0.0377 + 0.0624i   0.0310 + 0.0508i

  Columns 37 through 40

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0018 - 0.0031i   0.0018 + 0.0029i  -0.0017 - 0.0029i   0.0039 + 0.0062i
   0.0274 + 0.0447i   0.0197 + 0.0319i   0.0160 + 0.0258i   0.0041 + 0.0066i

  Columns 41 through 44

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0040 + 0.0063i  -0.0016 - 0.0028i   0.0019 + 0.0031i  -0.0017 - 0.0030i
   0.0042 + 0.0067i   0.0160 + 0.0258i   0.0197 + 0.0320i   0.0274 + 0.0448i

  Columns 45 through 48

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0017 + 0.0028i  -0.0015 - 0.0027i   0.0015 + 0.0026i  -0.0013 - 0.0025i
   0.0310 + 0.0508i   0.0377 + 0.0624i   0.0409 + 0.0680i   0.0468 + 0.0787i

  Columns 49 through 52

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0013 + 0.0023i  -0.0011 - 0.0023i   0.0010 + 0.0021i  -0.0010 - 0.0020i
   0.0495 + 0.0837i   0.0546 + 0.0934i   0.0569 + 0.0979i   0.0610 + 0.1065i

  Columns 53 through 56

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0008 + 0.0018i  -0.0007 - 0.0017i   0.0005 + 0.0015i  -0.0005 - 0.0014i
   0.0628 + 0.1105i   0.0660 + 0.1180i   0.0673 + 0.1214i   0.0695 + 0.1277i

  Columns 57 through 60

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0002 + 0.0014i  -0.0003 - 0.0012i   0.0000 + 0.0012i  -0.0001 - 0.0067i
   0.0703 + 0.1306i   0.0713 + 0.1361i   0.0716 + 0.1380i   0.0717 + 0.1464i

  Columns 61 through 64

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0001 - 0.0068i   0.0000 + 0.0011i  -0.0003 - 0.0012i   0.0002 + 0.0014i
   0.0717 + 0.1463i   0.0716 + 0.1380i   0.0713 + 0.1361i   0.0703 + 0.1307i

  Columns 65 through 68

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0006 - 0.0015i   0.0004 + 0.0015i  -0.0008 - 0.0018i   0.0007 + 0.0017i
   0.0695 + 0.1276i   0.0673 + 0.1214i   0.0660 + 0.1179i   0.0628 + 0.1105i

  Columns 69 through 72

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0011 - 0.0021i   0.0009 + 0.0020i  -0.0013 - 0.0023i   0.0011 + 0.0023i
   0.0610 + 0.1065i   0.0568 + 0.0979i   0.0545 + 0.0934i   0.0495 + 0.0837i

  Columns 73 through 76

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0015 - 0.0026i   0.0013 + 0.0025i  -0.0017 - 0.0028i   0.0015 + 0.0027i
   0.0467 + 0.0786i   0.0408 + 0.0680i   0.0377 + 0.0624i   0.0310 + 0.0508i

  Columns 77 through 80

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0019 - 0.0031i   0.0017 + 0.0029i  -0.0018 - 0.0029i   0.0038 + 0.0063i
   0.0273 + 0.0447i   0.0197 + 0.0320i   0.0160 + 0.0258i   0.0040 + 0.0066i

  Columns 81 through 84

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0039 + 0.0063i  -0.0018 - 0.0027i   0.0018 + 0.0031i  -0.0018 - 0.0029i
   0.0041 + 0.0067i   0.0160 + 0.0258i   0.0197 + 0.0320i   0.0274 + 0.0448i

  Columns 85 through 88

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0016 + 0.0028i  -0.0016 - 0.0027i   0.0014 + 0.0026i  -0.0014 - 0.0025i
   0.0310 + 0.0508i   0.0377 + 0.0624i   0.0409 + 0.0680i   0.0468 + 0.0787i

  Columns 89 through 92

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0012 + 0.0023i  -0.0012 - 0.0022i   0.0009 + 0.0021i  -0.0010 - 0.0020i
   0.0495 + 0.0837i   0.0546 + 0.0934i   0.0569 + 0.0980i   0.0610 + 0.1065i

  Columns 93 through 96

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0007 + 0.0018i  -0.0008 - 0.0017i   0.0005 + 0.0015i  -0.0006 - 0.0014i
   0.0628 + 0.1105i   0.0660 + 0.1180i   0.0673 + 0.1214i   0.0695 + 0.1277i

  Columns 97 through 100

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0002 + 0.0014i  -0.0003 - 0.0012i   0.0000 + 0.0012i  -0.0001 - 0.0067i
   0.0703 + 0.1306i   0.0713 + 0.1361i   0.0716 + 0.1380i   0.0717 + 0.1464i

  Columns 101 through 104

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0001 - 0.0068i   0.0000 + 0.0012i  -0.0003 - 0.0012i   0.0002 + 0.0014i
   0.0717 + 0.1463i   0.0716 + 0.1380i   0.0713 + 0.1361i   0.0703 + 0.1306i

  Columns 105 through 108

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0005 - 0.0015i   0.0005 + 0.0015i  -0.0008 - 0.0018i   0.0007 + 0.0017i
   0.0695 + 0.1276i   0.0673 + 0.1214i   0.0660 + 0.1179i   0.0628 + 0.1105i

  Columns 109 through 112

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0010 - 0.0021i   0.0010 + 0.0020i  -0.0012 - 0.0023i   0.0012 + 0.0022i
   0.0610 + 0.1065i   0.0568 + 0.0979i   0.0546 + 0.0934i   0.0495 + 0.0837i

  Columns 113 through 116

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0014 - 0.0026i   0.0014 + 0.0025i  -0.0016 - 0.0028i   0.0016 + 0.0027i
   0.0467 + 0.0786i   0.0408 + 0.0679i   0.0377 + 0.0624i   0.0310 + 0.0508i

  Columns 117 through 120

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0018 - 0.0031i   0.0018 + 0.0029i  -0.0017 - 0.0029i   0.0039 + 0.0062i
   0.0274 + 0.0447i   0.0197 + 0.0319i   0.0160 + 0.0258i   0.0041 + 0.0066i

  Columns 121 through 124

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0040 + 0.0063i  -0.0016 - 0.0028i   0.0019 + 0.0031i  -0.0017 - 0.0030i
   0.0042 + 0.0067i   0.0160 + 0.0258i   0.0197 + 0.0320i   0.0274 + 0.0448i

  Columns 125 through 128

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0017 + 0.0028i  -0.0015 - 0.0027i   0.0015 + 0.0026i  -0.0013 - 0.0025i
   0.0310 + 0.0508i   0.0377 + 0.0624i   0.0409 + 0.0680i   0.0468 + 0.0787i

  Columns 129 through 132

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0013 + 0.0023i  -0.0011 - 0.0023i   0.0010 + 0.0021i  -0.0010 - 0.0020i
   0.0495 + 0.0837i   0.0546 + 0.0934i   0.0569 + 0.0979i   0.0610 + 0.1065i

  Columns 133 through 136

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0008 + 0.0018i  -0.0007 - 0.0017i   0.0005 + 0.0015i  -0.0005 - 0.0014i
   0.0628 + 0.1105i   0.0660 + 0.1180i   0.0673 + 0.1214i   0.0695 + 0.1277i

  Columns 137 through 140

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
   0.0002 + 0.0014i  -0.0003 - 0.0012i   0.0000 + 0.0012i  -0.0001 - 0.0067i
   0.0703 + 0.1306i   0.0713 + 0.1361i   0.0716 + 0.1380i   0.0717 + 0.1464i

  Columns 141 through 144

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0001 - 0.0068i   0.0000 + 0.0011i  -0.0003 - 0.0012i   0.0002 + 0.0014i
   0.0717 + 0.1463i   0.0716 + 0.1380i   0.0713 + 0.1361i   0.0703 + 0.1307i

  Columns 145 through 148

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0006 - 0.0015i   0.0004 + 0.0015i  -0.0008 - 0.0018i   0.0007 + 0.0017i
   0.0695 + 0.1276i   0.0673 + 0.1214i   0.0660 + 0.1179i   0.0628 + 0.1105i

  Columns 149 through 152

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0011 - 0.0021i   0.0009 + 0.0020i  -0.0013 - 0.0023i   0.0011 + 0.0023i
   0.0610 + 0.1065i   0.0568 + 0.0979i   0.0545 + 0.0934i   0.0495 + 0.0837i

  Columns 153 through 156

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0015 - 0.0026i   0.0013 + 0.0025i  -0.0017 - 0.0028i   0.0015 + 0.0027i
   0.0467 + 0.0786i   0.0408 + 0.0680i   0.0377 + 0.0624i   0.0310 + 0.0508i

  Columns 157 through 160

   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i   0.0000 + 0.0000i
  -0.0019 - 0.0031i   0.0017 + 0.0029i  -0.0018 - 0.0029i   0.0038 + 0.0063i
   0.0273 + 0.0447i   0.0197 + 0.0320i   0.0160 + 0.0258i   0.0040 + 0.0066i

Create a microstrip patch antenna using 'FR4' as the dielectric substrate.

d = dielectric('FR4');
pm = patchMicrostrip('Length',75e-3, 'Width',37e-3,                 ...
        'GroundPlaneLength',120e-3, 'GroundPlaneWidth',120e-3, ...
        'Substrate',d)
show(pm)
pm = 

  patchMicrostrip with properties:

               Length: 0.0750
                Width: 0.0370
               Height: 0.0060
            Substrate: [1x1 dielectric]
    GroundPlaneLength: 0.1200
     GroundPlaneWidth: 0.1200
    PatchCenterOffset: [0 0]
           FeedOffset: [-0.0187 0]
                 Tilt: 0
             TiltAxis: [1 0 0]
                 Load: [1x1 lumpedElement]

Plot the current distribution on the antenna at a frequency of 1.67 GHz.

figure
current(pm,1.67e9,'dielectric')

Input Arguments

collapse all

Antenna or array object, specified as a scalar handle.

Frequency to calculate current distribution, specified as a scalar in Hz.

Example: 70e6

Data Types: double

Output Arguments

collapse all

x, y, z components of current distribution, returned as a 3-by-n complex matrix in A/m. The value of the current is calculated on every triangle mesh or every dielectric tetrahedron face on the surface of an antenna or array.

See Also

|

Introduced in R2015a

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