diff options
Diffstat (limited to 'Electronic_Communication_Systems_by_Roy_Blake/Chapter7.ipynb')
| -rw-r--r-- | Electronic_Communication_Systems_by_Roy_Blake/Chapter7.ipynb | 270 |
1 files changed, 270 insertions, 0 deletions
diff --git a/Electronic_Communication_Systems_by_Roy_Blake/Chapter7.ipynb b/Electronic_Communication_Systems_by_Roy_Blake/Chapter7.ipynb new file mode 100644 index 00000000..3756f68c --- /dev/null +++ b/Electronic_Communication_Systems_by_Roy_Blake/Chapter7.ipynb @@ -0,0 +1,270 @@ +{ + "cells": [ + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "# Chapter 7 : Digital Communication" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 1 : pg 285" + ] + }, + { + "cell_type": "code", + "execution_count": 1, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "maximum data rate for four-level code in the available bandwidth 12.8 kb/s\n", + "maximum data rate for four-level code in the available bandwidth 37.21 kb/s\n" + ] + } + ], + "source": [ + " \n", + "#page no 285\n", + "#prob no 7.1\n", + "#calculate the max data rate in both cases\n", + "from math import log\n", + "# In the given problem a signal is transmitted using a four level code\n", + "#given\n", + "M=4.;\n", + "B=3.2;# in KKz\n", + "SNR=35.;#in dB\n", + "#calculations and results\n", + "#By using Shannon-Hartley theorem, ignoring noise we have\n", + "c=2*B*log(M) / log(2);\n", + "print 'maximum data rate for four-level code in the available bandwidth',c,'kb/s'\n", + "#Now we have to use Shannon limit to find the maximum data rate for any code\n", + "#SNR in power ratio is \n", + "SNR1=10**(35./10.);\n", + "C=B*log(1+SNR1) /log(2);\n", + "print 'maximum data rate for four-level code in the available bandwidth',round(C,2),'kb/s'\n", + "# Both results are maxima, we have to choose lesser of the two.\n", + "# Therefore we choose c=12.8kp/s" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 2 : pg 289" + ] + }, + { + "cell_type": "code", + "execution_count": 2, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "The audible frequency is 14.1 KHz\n" + ] + } + ], + "source": [ + " \n", + "#page no. 289\n", + "# prob no. 7.2\n", + "# In the given problem\n", + "#calculate the audible frequency \n", + "#given\n", + "fm = 30.# in KHz\n", + "fs = 44.1#sampling rate in KHz\n", + "#calculations\n", + "fa = fs - fm# audible frequency\n", + "#results\n", + "print 'The audible frequency is',fa,'KHz'" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 3 : pg 291" + ] + }, + { + "cell_type": "code", + "execution_count": 3, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "a) The number of levels with m=8 are 256.0 levels\n", + "b) The number of levels with m=16 are 65536 levels\n" + ] + } + ], + "source": [ + " \n", + "#page no 291\n", + "#prob no 7.3\n", + "#calculate the number of levels in both cases\n", + "#part a: no of samples,\n", + "#given\n", + "m=8.;\n", + "#calculations and results\n", + "N=2**m;# the number of levels\n", + "print 'a) The number of levels with m=8 are',N,'levels'\n", + "# part b:\n", + "m=16;\n", + "N=2**m;# the number of levels\n", + "print 'b) The number of levels with m=16 are',N,'levels'" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 4 : pg 292" + ] + }, + { + "cell_type": "code", + "execution_count": 4, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "Dynamic range for a linear PCM 98.08 dB\n" + ] + } + ], + "source": [ + " \n", + "# page no 292\n", + "# prob no 7.4\n", + "#calculate the dynamic range\n", + "#In the given problem\n", + "#given\n", + "m=16.;\n", + "#calculations\n", + "DR=1.76 +6.02*m ; #Dynamic range for a linear PCM in dB\n", + "#results\n", + "print 'Dynamic range for a linear PCM',DR,'dB'" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 5 : pg 295" + ] + }, + { + "cell_type": "code", + "execution_count": 5, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "The minimum data rate needed to transmit audio is 560.0 Kb/s\n" + ] + } + ], + "source": [ + " \n", + "#page no 295\n", + "# prob no 7.5\n", + "#calculate the min data rate required\n", + "# in the given problem\n", + "#given\n", + "fs=40.; m=14;\n", + "#calculations\n", + "# the minimum data rate needed to transmit audio is given by\n", + "D=fs*m;\n", + "#results\n", + "print 'The minimum data rate needed to transmit audio is ',D,'Kb/s'" + ] + }, + { + "cell_type": "markdown", + "metadata": {}, + "source": [ + "## Example 6 : pg 294" + ] + }, + { + "cell_type": "code", + "execution_count": 6, + "metadata": { + "collapsed": false + }, + "outputs": [ + { + "name": "stdout", + "output_type": "stream", + "text": [ + "The maximum output voltage produced is 0.876 volts\n" + ] + } + ], + "source": [ + " \n", + "# page no 294\n", + "# prob no 7.6\n", + "#calculate the max output voltage required\n", + "# In the given problem, input to a mu-law compresser is +ve,\n", + "# with its voltage one-half the max value\n", + "from math import log\n", + "#given\n", + "u=255.;\n", + "Vi=1.;#maximum input value is considered as unity volts\n", + "vi=0.5;\n", + "V0=1.;#consider maximum output voltage as unity volts\n", + "#calculations\n", + "vo=V0* log(1+u*vi/Vi)/log(1+u);\n", + "#results\n", + "print 'The maximum output voltage produced is',round(vo,3),'volts'" + ] + } + ], + "metadata": { + "kernelspec": { + "display_name": "Python 2", + "language": "python", + "name": "python2" + }, + "language_info": { + "codemirror_mode": { + "name": "ipython", + "version": 2 + }, + "file_extension": ".py", + "mimetype": "text/x-python", + "name": "python", + "nbconvert_exporter": "python", + "pygments_lexer": "ipython2", + "version": "2.7.11" + } + }, + "nbformat": 4, + "nbformat_minor": 0 +} |