{
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"name": "",
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"worksheets": [
{
"cells": [
{
"cell_type": "heading",
"level": 1,
"metadata": {},
"source": [
"Chapter 9: Analog Signals"
]
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.1, Page 235"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable Declaration\n",
"\n",
"Bs=4.2 #Signal Bandwidth(MHz)\n",
"delf=2.56 #Deviation Ratio\n",
"\n",
"#Calculation\n",
"\n",
"delF=Bs*delf #Peak Deviation(MHz)\n",
"BIF=2*(delF+Bs) #Signal Bandwidth(MHz)\n",
"BIF=round(BIF,1)\n",
"#Results\n",
"\n",
"print \"The peak deviation is:\" , delF,\"MHz\"\n",
"print \"Signal Bandwidth is\" , BIF,\"MHz\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The peak deviation is: 10.752 MHz\n",
"Signal Bandwidth is 29.9 MHz\n"
]
}
],
"prompt_number": 1
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.2, Page 236"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable Declaration\n",
"\n",
"delF=200 #Peak Deviation(kHz)\n",
"f=0.8 #Test tone frequency (kHz)\n",
"\n",
"#Calculation\n",
"\n",
"m=delF/f #Modualtion index\n",
"B=2*(delF+f) #Bandwidth of the signal(kHz)\n",
"\n",
"#Results\n",
"\n",
"print \"The modulation index is\" , m\n",
"print \"Bandwidth of the signal is\", B,\"kHz\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The modulation index is 250.0\n",
"Bandwidth of the signal is 401.6 kHz\n"
]
}
],
"prompt_number": 2
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.3, Page 236"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"#Variable Declaration\n",
"\n",
"Bs1=4.2 #Signal Bandwidth(MHz) of Example 9.1\n",
"delf=2.56 #Deviation Ratio of Example 9.1\n",
"\n",
"delF2=200 #Peak Deviation(kHz) of Example 9.2\n",
"Bs2=0.8 #Test tone frequency (kHz) of Example 9.2\n",
"\n",
"#Calculation\n",
"\n",
"delF1=Bs1*delf #Peak Deviation(MHz) of Example 9.1\n",
"\n",
"BIF1=2*(delF1+2*Bs1) #Signal Bandwidth(MHz) of Example 9.1 according to Carson's rule\n",
"BIF1=round(BIF1,1)\n",
"BIF2=2*(delF2+2*Bs2) #Signal Bandwidth(kHz) of Example 9.2 according to Carson's rule.\n",
"\n",
"#Results\n",
"\n",
"print \"Signal Bandwidth of Example 9.1 by Carson's rule is\",BIF1,\"MHz\"\n",
"\n",
"print \"Signal Bandwidth of Example 9.2 by Carson's rule is\",BIF2,\"kHz\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Signal Bandwidth of Example 9.1 by Carson's rule is 38.3 MHz\n",
"Signal Bandwidth of Example 9.2 by Carson's rule is 403.2 kHz\n"
]
}
],
"prompt_number": 3
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.4, Page 241"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"#Variable Declaration\n",
"\n",
"delf=5 #Deviation frequency (kHz)\n",
"Bs=1 #Test Tone Frequency (kHz)\n",
"CNR=30 #Carrier to noise ration(dB)\n",
"\n",
"#Calculation\n",
"\n",
"m=delf/Bs #Modulation Index\n",
"Gp=3*(m**2)*(m+1) #Processing gain for sinusoidal modulation\n",
"Gp=10*math.log10(Gp) #Converting Gp into dB\n",
"SNR=CNR+Gp\n",
"\n",
"Gp=round(Gp,1)\n",
"SNR=round(SNR,1)\n",
"\n",
"#Results\n",
"\n",
"print \"The receiver processing gain is\",Gp,\"dB\"\n",
"print \"The Signal to noise ratio is\", SNR,\"dB\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The receiver processing gain is 26.5 dB\n",
"The Signal to noise ratio is 56.5 dB\n"
]
}
],
"prompt_number": 4
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.5, Page 245"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"#Variable Declaration\n",
"\n",
"n=24 #Number of channels\n",
"g=13.57 #Peak/rms factor(dB)\n",
"b=3.1 #Channel Bandwidth(kHz)\n",
"P=4 #Emphasis improvement (dB)\n",
"W=2.5 #Noise weighting improvement(dB)\n",
"CNR=25 #Carrier to noise ratio (dB)\n",
"delFrms=35 #rms value of Peak Deviation(kHz)\n",
"fm=108 #Baseband frequency (kHz)\n",
"#Calculation\n",
" \n",
"L=10**((-1+4*math.log10(n))/20)\n",
"g=10**(g/20) #Converting process gain to ratio\n",
"delF=g*delFrms*L #Peak Deviation(Hz)\n",
"BIF=2*(delF+fm) #Signal Bandwidth(kHz) by Carson's rule\n",
"Gp=(BIF/b)*((delFrms/float(fm))**2) #Processing Gain\n",
"Gp=10*math.log10(Gp) #Converting Gp to dB\n",
"SNR=CNR+Gp+P+W #Signal to noise ratio for top channel in 24-channel FDM basseband signal\n",
"SNR=round(SNR,1)\n",
"#Results\n",
"\n",
"print \"Signal to noise ratio for top channel in 24-channel FDM Baseband signal is\", SNR,\"dB\"\n"
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"Signal to noise ratio for top channel in 24-channel FDM Baseband signal is 45.7 dB\n"
]
}
],
"prompt_number": 5
},
{
"cell_type": "heading",
"level": 2,
"metadata": {},
"source": [
"Example 9.6, Page 246"
]
},
{
"cell_type": "code",
"collapsed": false,
"input": [
"import math\n",
"#Variable Declaration\n",
"\n",
"delF=9 #Peak Deviation (MHz) \n",
"fm=4.2 #Baseband frequency(MHz)\n",
"SNR=62 #Signal to noise ration(dB)\n",
"M=11.8 #Noise weighing(P)+emphasis improvement(W)-implementation margin(IMP)\n",
"\n",
"#Calculation\n",
"\n",
"D=delF/fm #Modulation Index\n",
"GPV=12*(D**2)*(D+1) #Processing Gain for TV\n",
"GPV=10*math.log10(GPV) #Converting GPV into dB\n",
"CNR=SNR-GPV-M #carrier to noise ratio(dB)\n",
"CNR=round(CNR,1)\n",
"#Results\n",
"\n",
"print \"The Carrier to noise ratio required at the input of FM detector is\",CNR,\"dB\""
],
"language": "python",
"metadata": {},
"outputs": [
{
"output_type": "stream",
"stream": "stdout",
"text": [
"The Carrier to noise ratio required at the input of FM detector is 27.8 dB\n"
]
}
],
"prompt_number": 6
}
],
"metadata": {}
}
]
}