{ "metadata": { "name": "", "signature": "sha256:948be1cc9ed00129c705ab5eed5191c57dcf55220270f926d97c4b4918eda1ba" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Ch-10 : Striplines & Microstrip lines" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 554 Example 10.1" ] }, { "cell_type": "code", "collapsed": false, "input": [ "from __future__ import division\n", "from math import exp, log10, pi, sqrt, log\n", "#Given,\n", "\n", "z0=50 #ohm\n", "t=0.001 #mm\n", "b=0.32 #cm\n", "er=2.20 \n", "tandel= 0.0005 \n", "rs=0.026 #ohm\n", "f=10e9 #Hz\n", "c=3e8 #m/sec\n", "\n", "p=sqrt(er)*z0 \n", "#As p<120\n", "w=b*(((30*pi)/p)-0.441)\n", "print 'Width %0.3f'%w,'cm'\n", "\n", "#Attenuation\n", "k=((2*pi*f*sqrt(er))/c) \n", "ad=(k*tandel)/2 \n", "\n", "#and\n", "A=1+((2*w)/(b-t))+(((b+t)/((b-t)*pi))*log(((2*b)-t)/t)) \n", "#Hence \n", "ac=(2.7e-3*rs*er*z0*A)/(30*pi*(b-t)*1e-2)\n", "#Total attenution\n", "a=ad+ac \n", "\n", "#Total attenution in db\n", "x=exp(a) \n", "alp=20*log10(x) #db/m\n", "\n", "#Total attenution in db/lambda:\n", "lam=c/(sqrt(er)*f) \n", "lamm=lam*1e2 \n", "alph=alp/lamm \n", "print 'Total attenution in db/lambda: %0.3f'%alph, 'db/lambda'\n", "\n", "\n", "#Answer in book for alph is given as 0.856 but it should be 0.0856 as value of f is taken as 10e10 but it should be 10e9" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Width 0.266 cm\n", "Total attenution in db/lambda: 0.856 db/lambda\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 555 Example 10.2" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "#Given,\n", "er=9.7 \n", "h=0.25 #mm\n", "w=0.25 #mm\n", "f=5e9 #Hz\n", "c=3e8 #m/s\n", "\n", "#(i) Dielectric constant\n", "dc=((er+1)/2)+(((er-1)/2)*(1/sqrt(1+12*h/w))) \n", "print 'Dielectric constant: %0.3f'%dc\n", "\n", "#(ii) Phase constant\n", "lam0=c/f \n", "pc=sqrt(dc)*(2*pi/lam0) \n", "print 'Phase constant: %0.3f'%(pc/100),'rad/m'\n", "\n", "#(iii) Microstrip wavelength\n", "lams=lam0/sqrt(dc) \n", "print 'Microstrip wavelength: %0.3f'%(lams*100),'cm'\n", "\n", "#(iv) Capacitance per unit length\n", "e0=8.854e-12 \n", "cap=(2*pi*e0)/log((8*h/w)-(w/(4*h))) \n", "print 'Capacitance per unit length: %0.3e'%cap, 'F/cm'\n", "\n", "#(v) Characterstic Impedance\n", "ci=(60/sqrt(dc))*log((8*h/w)+(w/(4*h))) \n", "print 'Characterstic impedance: %0.3f'%ci, 'ohm'" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Dielectric constant: 6.556\n", "Phase constant: 2.681 rad/m\n", "Microstrip wavelength: 2.343 cm\n", "Capacitance per unit length: 2.717e-11 F/cm\n", "Characterstic impedance: 49.447 ohm\n" ] } ], "prompt_number": 5 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 556 Example 10.3" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "#Given,\n", "er=5.23 \n", "w=10 #mils\n", "t=2.8 #mils\n", "h=7 #mils\n", "\n", "dc=((er+1)/2)+(((er-1)/2)*(1/sqrt(1+12*h/w))) \n", "print 'Dielectric constant: %0.3f'%dc\n", "\n", "#As w/h>1\n", "ci=(120*pi)/(sqrt(dc)*((w/h)+1.393+0.667*log((w/h)+1.444))) \n", "print 'Characterstic impedance: %0.3f'%ci, 'ohm'" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "Dielectric constant: 3.805\n", "Characterstic impedance: 54.822 ohm\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Page Number: 556 Example 10.4" ] }, { "cell_type": "code", "collapsed": false, "input": [ " \n", "#Given,\n", "\n", "q=2.5 \n", "dh=1.58 \n", "er=9 \n", "f=10 \n", "c=3e8 \n", "\n", "erff=((er+1)/2)+(((er-1)/2)*((1+(12/q))**(-1/2))) \n", "vp=(c/sqrt(erff))*erff \n", "fe1=c/(sqrt(vp)*2*dh*q) \n", "if f