path: root/Electronic_Communication_by_D._Roddy/Chapter4_Noise.ipynb

{
 "cells": [
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "# Chapter 4 Noise"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.2.1,Pg.no 120"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 1,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The value of thermal noise power is 4.002e-15 W\n",
      "The value of RMS noise voltage is 0.89 uV\n"
     ]
    }
   ],
   "source": [
    "from math import sqrt\n",
    "T=290.0\n",
    "BW=1*10**6          #Noise bandwidth in hertz\n",
    "k=1.38*10**-23      #Boltzman constant in J/K\n",
    "R=50.0              #Determination of thermal noise power Pn\n",
    "Pn=k*T*BW\n",
    "#Pn=round(Pn,1)\n",
    "print 'The value of thermal noise power is',Pn,'W'\n",
    "#Determination of RMS noise voltage\n",
    "En=sqrt(4*R*k*T*BW)\n",
    "En=En*(10**6)\n",
    "En=round(En,2)\n",
    "print 'The value of RMS noise voltage is',En,'uV'"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.2.2,Pg.no.122"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 2,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "a) i )The value of RMS noise voltage is 5.66 uV\n",
      "   ii)The value of RMS noise voltage is 8949245.77828 uV\n",
      "b)The value of RMS noise voltage is 10588890.4 uV\n",
      "c)The value of RMS noise voltage is 4783573.08 uV\n"
     ]
    }
   ],
   "source": [
    "from math import sqrt\n",
    "R1=20000.0\n",
    "R2=50000.0\n",
    "k=1.38*10**-23              #Boltzman constant in J/K\n",
    "T=290.0\n",
    "BW=100*10**3       #Determination of thermal noise voltage for 20Kohm resistor\n",
    "En1=sqrt(4*R1*k*T*BW)\n",
    "En1=En1*(10**6)\n",
    "En1=round(En1,2)\n",
    "print 'a) i )The value of RMS noise voltage is',En1,'uV'\n",
    "#Determination of thermal noise voltage for 50 kohm resistor\n",
    "En2=En1*sqrt(R2/R1)\n",
    "En2=En2*10**6\n",
    "print '   ii)The value of RMS noise voltage is',En2,'uV'\n",
    "#Determination of thermal noise voltage for 20K & 50k resistor in series\n",
    "Rser=R1+R2           #Series combination of R1 & R2\n",
    "En3=En1*sqrt(Rser/R1)\n",
    "En3=En3*10**6\n",
    "En3=round(En3,2)\n",
    "print 'b)The value of RMS noise voltage is',En3,'uV'\n",
    "#Determination of thermal noise voltage for 20K & 50k resistor in parellel\n",
    "Rpar=(R1*R2)/(R1+R2)         #parallel combination of R1 & R2\n",
    "En4=En1*sqrt(Rpar/R1)\n",
    "En4=En4*10**6\n",
    "En4=round(En4,2)\n",
    "print 'c)The value of RMS noise voltage is',En4,'uV'"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.2.3,Pg.no.128"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 3,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The value of Rd is 1.59 kohm\n",
      "The value of effective noise voltage is 0.02 uV\n"
     ]
    }
   ],
   "source": [
    "from math import sqrt,pi\n",
    "f=120*10**6\n",
    "c=25*10**-12         #capacitance of 12 pF\n",
    "Q=30.0               #Q−factor of the ckt is 30\n",
    "BW=10*10**3          #channel BW of the receiver is 10 KHz\n",
    "k=1.38*10**-23       #Boltzman constant in J/K\n",
    "T=290.0              #Room temp\n",
    "#Determination of effective noise voltage Rd appearing at i /p at room temp\n",
    "Rd=Q/(2*pi*f*c)\n",
    "Rd=Rd/1000\n",
    "Rd=round(Rd,2)\n",
    "print 'The value of Rd is',Rd,'kohm'\n",
    "Vn=sqrt(4*Rd*k*T*BW)\n",
    "Vn=Vn*10**6\n",
    "Vn=round(Vn,2)\n",
    "print 'The value of effective noise voltage is',Vn,'uV'"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.3.1,Pg.no.131"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 4,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The value of noise current In is 17.89 nA\n"
     ]
    }
   ],
   "source": [
    "from math import sqrt\n",
    "Idc=10**-3\n",
    "Bn=10**6           #Effective noise BW=1 MHz\n",
    "q=1.6*10**-19      #Charge on electron in coulombs\n",
    "#Determination of noise component current In in DC current of Idc=1 mA\n",
    "In=sqrt(2*Idc*q*Bn)\n",
    "In=In*10**9\n",
    "In=round(In,2)\n",
    "print 'The value of noise current In is',In,'nA'"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.11.1,Pg.no.135"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 5,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The value of shot noise current Ina is 4.0 nA\n",
      "The value of noise voltage across Rs is 600000000.0 uV\n",
      "The value of noise voltage across Rn is 6.93 uV\n",
      "The value of thermal noise voltage at Rs is 4.9 uV\n",
      "The value of total noise voltage Vn is 1000000.0 uV\n",
      "The value of signal to noise ratio is -220.0 dB\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "from math import pi,sqrt\n",
    "#An amplifier is given\n",
    "Rn=300.0        #Equivalent noise resistance\n",
    "Ieq=5*10**-6    #Equivalent noise current is 5 uA\n",
    "Rs=150.0        #Amplifier fed from 150 ohm,10 uV rms sinusoidal source\n",
    "Vs=10*10**-6\n",
    "Bn=10*10**6     #Noise BW is 10 MHz\n",
    "#Assume the following\n",
    "kT=4*10**-21    #k is Boltzman constant in J/K & T is room temp\n",
    "q=1.6*10**-19   #Charge on electron in coloumbs\n",
    "#Determination of shot noise current\n",
    "Ina=sqrt(2*q*Ieq*Bn)\n",
    "Ina=Ina*(10**9)\n",
    "print 'The value of shot noise current Ina is',Ina,'nA'\n",
    "#Noise voltage developed by this across source resistance is\n",
    "V=Ina*Rs\n",
    "V=V*(10**6)\n",
    "V=round(V,2)\n",
    "print 'The value of noise voltage across Rs is',V,'uV'\n",
    "#Noise voltage developed across Rn resistance is\n",
    "Vna=sqrt(4*Rn*kT*Bn)*10**6\n",
    "Vna=round(Vna,2)\n",
    "print 'The value of noise voltage across Rn is',Vna,'uV'\n",
    "#Determination of thermal noise voltage from source\n",
    "Vns=sqrt(4*Rs*kT*Bn)*10**6\n",
    "Vns=round(Vns,2)\n",
    "print 'The value of thermal noise voltage at Rs is',Vns,'uV'\n",
    "#Determination of total noise voltage at input\n",
    "Vn=(((V)**2)+((Vna)**2)+((Vns)**2))**(1/2)\n",
    "Vn=Vn*(10**6)\n",
    "print 'The value of total noise voltage Vn is',Vn,'uV'\n",
    "#Determination of signal to noise ratio in dB\n",
    "SNR=20*(math.log10(Vs/Vn))\n",
    "print 'The value of signal to noise ratio is',SNR,'dB'"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.12.1,Pg.no.136"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 6,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The value of output signal to noise ratio is 55.23 dB\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "SNR1=60.0\n",
    "l=3.0           #Determination of output signal to noise ratio\n",
    "SNR=(SNR1) -10*math.log10(l)\n",
    "SNR=round(SNR,2)\n",
    "print 'The value of output signal to noise ratio is',SNR,'dB'"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.12.2,Pg.no.137"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 14,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The value of output signal to noise ratio is 40.0 dB\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "SNRdB1=60.0      #SNR is 60 dB for Ist link\n",
    "SNRdB2=60.0      #SNR is 60 dB for IInd link\n",
    "SNRdB3=40.0      #SNR is 40 dB for IIIrd link\n",
    "#Determination of power in watt\n",
    "snr1=10**(-SNRdB1/10)\n",
    "snr2=10**(-SNRdB2/10)\n",
    "snr3=10**(-SNRdB3/10)\n",
    "#Determination of overall SNR\n",
    "SNR=snr3\n",
    "#Determination of total SNR in dB\n",
    "SNRdB=10*(-math.log10(SNR))\n",
    "print 'The value of output signal to noise ratio is',SNRdB,'dB'"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.13.1,Pg.no.139"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 15,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The value of output signal to noise ratio is 28.0 dB\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "SNRin=35.0 #SNR at i /p of amplifier\n",
    "F=7.0      #Noise figure of an amplifier\n",
    "#Determination of output SNR\n",
    "SNRout=SNRin-F\n",
    "print 'The value of output signal to noise ratio is',SNRout,'dB'"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.14.1,Pg.no.140"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 16,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The value of input noise is 0.08 pW\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "f=13.0  #Noise figure of an amplifier\n",
    "Bn=1*10**6\n",
    "kT=4*10**-21   #k is Boltzman constant in J/K & T is room temp\n",
    "F=10**(f/10)\n",
    "#Determination of equivalent amplifier input noise\n",
    "Pna=(F-1)*kT*Bn*10**12\n",
    "Pna=round(Pna,2)\n",
    "print 'The value of input noise is',Pna,'pW'"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.15.1,Pg.no.141"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 17,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The overall noise fig is 10.44 dB\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "f1=9.0     #Noise fig for amplifier\n",
    "f2=20.0    #Noise fig for mixer\n",
    "g=15.0     #power gain\n",
    "#Converting dB in power ratio\n",
    "F1=10**(f1/10)\n",
    "F2=10**(f2/10)\n",
    "G=10**(g/10)\n",
    "#Determination of overall noise fig . reffered at i / p\n",
    "F=F1+(F2-1)/G  #converting in dB\n",
    "FdB=10*math.log10(F)\n",
    "FdB=round(FdB,2)\n",
    "print 'The overall noise fig is',FdB,'dB'"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.17.1,Pg.no.143"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 18,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The value of noise factor is 1\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "F=6.0      #Noise fig .=6 dB\n",
    "#Determination of noise factor\n",
    "Fn=10**(6/10)\n",
    "print 'The value of noise factor is',Fn"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.18.1,Pg.no.144"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 19,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The value of equivalent noise at room temp is 4306.19 k\n",
      "The value of equivalent noise at noise temp=90 is 90.04 K\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "f=12.0 \n",
    "Tm=290.0    #Room temp value\n",
    "T=90.0\n",
    "g=50.0      #calculating power ratio\n",
    "F=10**(f/10)\n",
    "G=10**(g/10)\n",
    "#Determination of equivalent noise at room temp\n",
    "Tem=(F-1)*Tm\n",
    "Tem=round(Tem,2)\n",
    "print 'The value of equivalent noise at room temp is',Tem,'k'\n",
    "#Determination of equivalent noise at 90 k temp\n",
    "Te=T+(Tem/G)\n",
    "Te=round(Te,2)\n",
    "print 'The value of equivalent noise at noise temp=90 is',Te,'K'"
   ]
  },
  {
   "cell_type": "markdown",
   "metadata": {},
   "source": [
    "## Example 4.19.1,Pg.no.146"
   ]
  },
  {
   "cell_type": "code",
   "execution_count": 20,
   "metadata": {
    "collapsed": false
   },
   "outputs": [
    {
     "name": "stdout",
     "output_type": "stream",
     "text": [
      "The value of hot temp Th is 7574.47 k\n",
      "The value of equivalent noise temp Te is 759.14 K\n"
     ]
    }
   ],
   "source": [
    "import math\n",
    "enr=14.0\n",
    "To=290.0          #Room temp in K\n",
    "y=9.0             #Y−factor is 9 dB\n",
    "#converting dB in power ratio\n",
    "ENR=10**(enr/10)\n",
    "Y=10**(y/10)      #From def of ENR the hot temp is\n",
    "Th=To*(ENR+1)\n",
    "Th=round(Th,2)\n",
    "print 'The value of hot temp Th is',Th,'k'\n",
    "#Determination of equivalent noise temp\n",
    "Te=(Th-(Y*To))/(Y-1)\n",
    "Te=round(Te,2)\n",
    "print 'The value of equivalent noise temp Te is',Te,'K'"
   ]
  }
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