{
"metadata": {
"name": "",
"signature": "sha256:036aa35bf5e5de2a2351f2b120a2084a8b3fc2b376331b57004e9eccc3893299"
},
"nbformat": 3,
"nbformat_minor": 0,
"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 11: Antennas"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.1, page no. 292"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"# Variable Declaration\n",
"f1 = 1.00*pow(10,6) # Operating Frequency (Hz)\n",
"f2 = 10.00*pow(10,3) # Operating Frequency (Hz)\n",
"c = 3.00*pow(10,8) # Speed of light in vacuum (m/s)\n",
"\n",
"# Calculation\n",
"Lambda1 = c/f1 # Mechanical Length (m)\n",
"Lambda2 = c/f2 # Mechanical Length (m)\n",
"\n",
"# Result\n",
"print \"(a) Mechanical Length at 1 MHz, Lambda1 =\",round(Lambda1),\"m\"\n",
"print \"(b) Mechanical Length at 10 kHz, Lambda2 =\",round(Lambda2),\"m\"\n",
"print \" Increase in Length =\",round(Lambda2/Lambda1),\"times\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"(a) Mechanical Length at 1 MHz, Lambda1 = 300.0 m\n",
"(b) Mechanical Length at 10 kHz, Lambda2 = 30000.0 m\n",
" Increase in Length = 100.0 times\n"
]
}
],
"prompt_number": 16
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.2, page no. 294"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"# Variable Declaration \n",
"f = 1.00*pow(10,6) # Operating Frequency (Hz)\n",
"Le = 30 # Hertzian Dipole Length (m)\n",
"I = 5 # Current value (A)\n",
"r = 1.00*pow(10,3) # Distance (m)\n",
"Theeta = 90 # Angle (degrees)\n",
"c = 3.00*pow(10,8) # Speed of light in vacuum (m/s)\n",
"\n",
"# Calculation\n",
"import math\n",
"Lambda = c/f # Wavelength (m)\n",
"E = ((60*math.pi*Le*I)/Lambda*r)*math.sin(Theeta*math.pi/180) # Calculation of Field Strength (s/m)\n",
"\n",
"# Result\n",
"print \"Field Strength at a distance of 1 km and at an angle of 90 degrees, E =\",round(E/(math.pi*pow(10,3))),\"*pi*10^(-3) us/m\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Field Strength at a distance of 1 km and at an angle of 90 degrees, E = 30.0 *pi*10^(-3) us/m\n"
]
}
],
"prompt_number": 15
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.3, page no. 296"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"# Variable Declaration \n",
"f = 500*pow(10,3) # Operating Frequency (Hz)\n",
"vel = 3.00*pow(10,8) # Speed of light in vacuum (m/s)\n",
"Vf = 0.95 # Velocity Factor\n",
"\n",
"# Calculation\n",
"import math # Math Library\n",
"Le = vel/f*Vf # Length of the antenna (m)\n",
"\n",
"# Result\n",
"print \"The Length of the Antenna, Le =\",round(Le),\"m or\",round(Le*3.936),\"ft\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The Length of the Antenna, Le = 570.0 m or 2244.0 ft\n"
]
}
],
"prompt_number": 17
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.4, page no. 299"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"# Variable Declaration \n",
"P1 = 1*pow(10,3) # Power of Half Wave Dipole antenna (w)\n",
"A = 2.15 # Gain (dB)\n",
"\n",
"# Calculation\n",
"import math # Math Library\n",
"P2 = pow(10,A/10)*P1 # Power delivered (w)\n",
"\n",
"# Result\n",
"print \"The power delivered to the isotropic antenna to match the field strength of directional antenna, P2 =\",round(P2,1),\"W\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The power delivered to the isotropic antenna to match the field strength of directional antenna, P2 = 1640.6 W\n"
]
}
],
"prompt_number": 18
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.5, page no. 300"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"# Variable Declaration \n",
"P = 1.00*pow(10,3) # Input Power (W)\n",
"field_gain = 2 # Field Gain\n",
"E = 0.5 # (*100) Efficiency (%)\n",
"\n",
"# Calculation\n",
"import math # Math Library\n",
"Po = P*E # Power fed (W)\n",
"erp = Po*pow(field_gain,2) # Effective Radiated Power (w)\n",
"\n",
"\n",
"# Result\n",
"print \" The Effective Radiated Power, erp =\",round(erp),\"W\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
" The Effective Radiated Power, erp = 2000.0 W\n"
]
}
],
"prompt_number": 19
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.6, page no. 300"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"# Variable Declaration \n",
"P_in = 800 # Input Power (W)\n",
"E_lost = 0.25 # (*100) Loss Percentage (%)\n",
"\n",
"# Calculation\n",
"import math # Math Library\n",
"Pd = E_lost*P_in # Power Lost (W)\n",
"P_rad = P_in-Pd # Radiated Power (W)\n",
"\n",
"# Result\n",
"print \"Radiated Power, P_rad =\",round(P_rad),\"W\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Radiated Power, P_rad = 600.0 W\n"
]
}
],
"prompt_number": 20
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.7, page no. 301"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"\n",
"# Variable Declaration \n",
"R_rad = 100 # Radiation Resistance (Ohms)\n",
"E = 0.75 # (*100) Efficiency (%)\n",
"\n",
"# Calculation\n",
"import math # Math Library\n",
"Rd = R_rad/E-R_rad # Antenna Resistance (Ohms)\n",
"\n",
"# Result\n",
"print \"Antenna Resistance, Rd =\",round(Rd,2),\"Ohms\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Antenna Resistance, Rd = 33.33 Ohms\n"
]
}
],
"prompt_number": 10
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.8, page no. 309"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"# Variable Declaration \n",
"Zs = 5 # Impedance of the transmission line (Ohms)\n",
"Zr = 70 # Impedance of the antenna (Ohms)\n",
"\n",
"# Calculation\n",
"import math # Math Library\n",
"Z = Zs*Zr # Characteristic Impedance (Ohms)\n",
"\n",
"# Result\n",
"print \"The characteristic impedance of the matching section, Z =\",round(Z),\"Ohms\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The characteristic impedance of the matching section, Z = 350.0 Ohms\n"
]
}
],
"prompt_number": 21
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.9, page no. 316"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"# Variable Declaration \n",
"D = 2 # Mouth diameter of reflector (m)\n",
"f = 6.00*pow(10,9) # Operating Frequency (Hz)\n",
"c = 3.00*pow(10,8) # Speed of light in vacuum (m/s)\n",
"\n",
"# Calculation\n",
"import math # Math Library\n",
"Lambda = c/f # Wavelength (m)\n",
"phi_o = 2*70*Lambda/D # Beam width between nulls of a paraboloid reflector (degrees)\n",
"\n",
"# Result\n",
"print \"The beam width between nulls of a paraboloid reflector, phi_o =\",round(phi_o,1),\"degrees\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The beam width between nulls of a paraboloid reflector, phi_o = 3.5 degrees\n"
]
}
],
"prompt_number": 22
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 11.10, page no. 317"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"\n",
"# Variable Declaration \n",
"D = 200 # Mouth diameter of reflector (m)\n",
"Lambda = 5 # Wavelength (m)\n",
"\n",
"# Calculation\n",
"import math # Math Library\n",
"Ap = 6*pow(D/Lambda,2) # Gain of the antenna\n",
"\n",
"# Result\n",
"print \" The gain of the antenna, Ap =\",round(Ap)"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
" The gain of the antenna, Ap = 9600.0\n"
]
}
],
"prompt_number": 13
}
],
"metadata": {}
}
]
}