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"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 01 : Antenna Principles"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Exa 1.1 : page 1.42"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from __future__ import division\n",
"from math import pi\n",
"#given data :\n",
"E=4.0 #in V/m\n",
"Eta=120*pi #constant\n",
"#Formula : E/H=Eta\n",
"H=E/Eta #in A/m\n",
"print \"Strength of magnetic field in free space = %0.4f A/m \" %H"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Strength of magnetic field in free space = 0.0106 A/m \n"
]
}
],
"prompt_number": 5
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Exa 1.2 : page 1.42"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import pi\n",
"#given data :\n",
"H=5.2 #in mA/m\n",
"Eta=120*pi #constant\n",
"#Formula : E/H=Eta\n",
"E=H*10**-3*Eta #in V/m\n",
"print \"Strength of Electric field in free space =\",round(E),\"V/m\" "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Strength of Electric field in free space = 2.0 V/m\n"
]
}
],
"prompt_number": 4
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Exa 1.3 : page 1.42"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#given data :\n",
"I=20.0 #in A\n",
"Rr=100.0 #in Ohm\n",
"#Formula : Wr=I**2*R\n",
"Wr=I**2*Rr #in W\n",
"print \"Radiated power = %0.f kW \" %(Wr/1000) "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Radiated power = 40 kW \n"
]
}
],
"prompt_number": 3
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Exa 1.4 : page 1.42"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import sqrt\n",
"#given data :\n",
"W=625.0 #in KW\n",
"r=30.0 #in Km\n",
"Erms=sqrt(90*W*1000)/(r*1000) #in V/m\n",
"print \"Strength of Electric field at 30Km away = %0.f mV/m \" %(Erms*1000) "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Strength of Electric field at 30Km away = 250 mV/m \n"
]
}
],
"prompt_number": 6
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Exa 1.6 : page 1.43"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import pi\n",
"#given data :\n",
"le=50.0 #in m\n",
"f=100.0 #in MHz\n",
"lamda=300.0/(f) #in m\n",
"Rr=(160*(pi)**2)*(le/lamda)**2 #in Ohm\n",
"print \"Radiation Resistance = %0.2f Mohm \" %(Rr/10**6) \n",
"#Note : Answer in the book is wrong"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Radiation Resistance = 0.44 Mohm \n"
]
}
],
"prompt_number": 12
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Exa 1.7 : page 1.44"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import pi\n",
"#given data :\n",
"l=30 #in m\n",
"Irms=20 #in A\n",
"f=1 #in MHz\n",
"r=10 #in Km\n",
"r=r*1000 #in m\n",
"le=2*l/pi #in m\n",
"lamda=300/(f) #in m\n",
"Erms=120*pi*le*Irms/(lamda*r) #in V/m\n",
"print \"Field strength at 10Km distance = %0.2e V/m \" %Erms \n",
"#Note : Answer in the book is wrong"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Field strength at 10Km distance = 4.80e-02 V/m \n"
]
}
],
"prompt_number": 14
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Exa 1.8 : page 1.44"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import pi\n",
"#given data :\n",
"Rl=1.0 #in ohm\n",
"#Formula : Rr=80*pi**2*(l/lamda)**2\n",
"#Given l=lamda/10\n",
"#l/lamda=1/10\n",
"Rr=80*pi**2*(1.0/10)**2 #in Ohm\n",
"print \"Radiation resistance = %0.2f Ohm \" %(Rr) \n",
"Eta=Rr/(Rr+Rl) #Unitless\n",
"print \"Antenna Efficiency = %0.2f %% \" %(Eta*100) "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Radiation resistance = 7.90 Ohm \n",
"Antenna Efficiency = 88.76 % \n"
]
}
],
"prompt_number": 15
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Exa 1.9 : page 1.44"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import sqrt\n",
"#given data :\n",
"r=100 #in Km\n",
"W=100 #in KW\n",
"Erms=sqrt(90*W*1000)/(r*1000) #in V/m\n",
"print \"Strength of Electric Field = %0.2f V/m \" %Erms "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Strength of Electric Field = 0.03 V/m \n"
]
}
],
"prompt_number": 16
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Exa 1.10 : page 1.44"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import pi\n",
"#given data :\n",
"le=200.0 #in m\n",
"Irms=200 #in A\n",
"f=300 #in KHz\n",
"r=10 #in Km\n",
"c=3*10**8 #speed of light i m/s\n",
"lamda=c/(f*1000) #in m\n",
"Erms=120*pi*le*Irms/(lamda*r*10**3) #in V/m\n",
"print \"Field strength at 10Km distance = %0.4f V/m\" %(Erms) \n",
"Rr=(160*(pi)**2)*(le/lamda)**2 #in Ohm\n",
"W=Irms**2*Rr #in Watts\n",
"print \"Radiated Power = %0.2f MW \" %(W/10**6) \n",
"#Note : Answer is wrong in the book. Unit of answer in the book is written mW instead of MW by mistake."
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Field strength at 10Km distance = 1.5080 V/m\n",
"Radiated Power = 2.53 MW \n"
]
}
],
"prompt_number": 21
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Exa 1.11 : page 1.45"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import pi\n",
"#given data :\n",
"#Formula : Rr=80*pi**2*(l/lamda)**2\n",
"#Given l=lamda/60\n",
"#l/lamda=1/60\n",
"Rr=80*pi**2*(1.0/60)**2 #in Ohm\n",
"print \"Radiation resistance = %0.3f Ohm \" %Rr "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Radiation resistance = 0.219 Ohm \n"
]
}
],
"prompt_number": 23
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Exa 1.12 : page 1.45"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#given data :\n",
"r=10.0 #in Km\n",
"Erms=10.0 #in mV/m\n",
"r1=20.0 #in Km\n",
"#Formula : Erms=sqrt(90*W)/r #in V/m\n",
"#Let swrt(90*W)=a\n",
"a=Erms*r \n",
"Erms1=a/r1 #in mV/m\n",
"print \"Field strength at 20Km distance = %0.f mV/m \" %Erms1 "
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Field strength at 20Km distance = 5 mV/m \n"
]
}
],
"prompt_number": 4
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Exa 1.13 : page 1.45"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"from math import pi\n",
"#given data :\n",
"r=1.0 #in Km\n",
"r=1*10**3 #in m\n",
"l=1.0 #in m\n",
"Irms=10.0 #in A\n",
"f=5.0 #in MHz\n",
"c=3*10**8 #speed of light i m/s\n",
"lamda=c/(f*10**6) #in m\n",
"le=2*l/pi #in m\n",
"Erms=120*pi*le*Irms/(lamda*r) #in V/m\n",
"print \"Field strength at 10Km distance = %0.4f V/m \" %Erms\n",
"#Note : Answer in the book is wrong. Mistake during value putting."
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Field strength at 10Km distance = 0.0400 V/m \n"
]
}
],
"prompt_number": 26
}
],
"metadata": {}
}
]
}