{ "metadata": { "name": "", "signature": "sha256:f6cde23ce2afec7e011f20ed56b14deeef046db9ca1319efd802d439a18d5a2d" }, "nbformat": 3, "nbformat_minor": 0, "worksheets": [ { "cells": [ { "cell_type": "heading", "level": 1, "metadata": {}, "source": [ "Chapter10:MICROWAVE CROSSED-FIELD TUBES(M TYPE)" ] }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg10.1.1:pg-448" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#(a) Calculate the cyclotron angular frequency\n", "em=1.759*(10**11) #em=e/m is the charge is to mass ratio of electron\n", "B0=0.336 #Magnetic flux density in Wb/m**2\n", "wc=(em)*B0 \n", "print\"The cyclotron angular frequency(in rad)is =\",\"{:.2e}\".format(wc),\"rad\" \n", "\n", "#(b) Calculate the cutoff voltage for a fixed B0\n", "a=5*(10**-2) #radius of cathode cylinder in meter\n", "b=10*(10**-2) #radius of vane edge to center in meter\n", "Voc=(em*(B0**2)*(b**2)*((1-((a/b)**2))**2))/8 \n", "Voc=Voc/(10**5) #converting Voc in KV\n", "print\"The cutoff voltage for a fixed B0(in KV)is =\",round(Voc,2),\"KV\" #calculation mistake in book\n", "\n", "#(c) Calculate the cutoff magnetic flux density for a fixed V0\n", "V0=26*(10**3) #Anode voltage in volt\n", "Boc=sqrt((8*V0)/em)/(b*(1-((a/b)**2))) \n", "Boc=Boc*1000 #converting Boc in mWb/m**2\n", "print\"The cutoff magnetic flux density for a fixed V0(in mWb/m**2)is =\",round(Boc,3),\"mWb/m2\" " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The cyclotron angular frequency(in rad)is = 5.91e+10 rad\n", "The cutoff voltage for a fixed B0(in KV)is = 139.63 KV\n", "The cutoff magnetic flux density for a fixed V0(in mWb/m**2)is = 14.499 mWb/m2\n" ] } ], "prompt_number": 2 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg10.1.1A:pg-452" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#(a) Calculate the angular resonant frequency\n", "f=9*(10**9) #Operating frequency in Hertz\n", "wr=2*math.pi*f #angular frequency\n", "print\"The angular resonant frequency(in rad)is =\",\"{:.3e}\".format(wr),\"rad\" \n", "\n", "#(b) Calculate the unloaded quality factor\n", "C=2.5*(10**-12) #vane capacitance in Farad\n", "Gr=2*(10**-4) #Resonator conductance in mho\n", "Qun=wr*C/Gr \n", "print\"The unloaded quality factor is=\",int(round(Qun))\n", "\n", "#(c) Calculate the loaded quality factor\n", "C=2.5*(10**-12) #vane capacitance in Farad\n", "Gr=2*(10**-4) #Resonator conductance in mho\n", "Gl=2.5*(10**-5) #loaded conductance in mho\n", "Ql=wr*C/(Gl+Gr) \n", "print\"The loaded quality factor is=\",int(Ql)\n", "\n", "#(d) Calculate the external quality factor\n", "C=2.5*(10**-12) #vane capacitance in Farad\n", "Gl=2.5*(10**-5) #loaded conductance in mho\n", "Qex=wr*C/Gl \n", "print\"The external quality factor is=\",int(round(Qex)) \n", "\n", "#(e) Calculate the circuit efficiency\n", "n=(1/(1+(Qex/Qun))) \n", "n=n*100 \n", "print\"The circuit efficiency(in %) is=\",round(n,2),\"%\"\n", "\n", "#(f) Calculate the electronic efficiency\n", "V0=5.5*(10**3) #Anode Voltage in volt\n", "I0=4.5 #Beam current in Ampere\n", "Plost=18.5*(10**3) #power loss in Watt\n", "ne=((V0*I0)-(Plost))/(V0*I0) \n", "ne=ne*100 \n", "print\"The electronic efficiency(in %) is=\",round(ne,2),\"%\" " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The angular resonant frequency(in rad)is = 5.655e+10 rad\n", "The unloaded quality factor is= 707\n", "The loaded quality factor is= 628\n", "The external quality factor is= 5655\n", "The circuit efficiency(in %) is= 11.11 %\n", "The electronic efficiency(in %) is= 25.25 %\n" ] } ], "prompt_number": 3 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg10.1.2:pg-457" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#(a) Calculate the Hull cutoff voltage for fixed Bo\n", "em=1.759*(10**11) #em=e/m is the charge to mass ratio of electron\n", "Bo=0.01 #Magnetic flux density in Wb/m**2\n", "d=5*(10**-2) #Distance between cathode and anode in meter\n", "Voc=(1.0/2)*(em)*(Bo**2)*(d**2) \n", "Voc=Voc/1000 #converting Voc in KV\n", "print\"The Hull cutoff voltage for fixed Bo (in KV)is =\",round(Voc),\"KV\"\n", "\n", "#(b) Calculate the Hull cutoff magnetic field density for fixed Vo\n", "V0=10*(10**3) #Anode voltage in Volt\n", "Boc=(1.0/d)*sqrt((2*V0)/(em)) \n", "Boc=Boc*1000 #in mWb/m2\n", "print\"The Hull cutoff magnetic field density for fixed Vo(in mWb/m**2)is =\",round(Boc,2),\"mWb/m2\" " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The Hull cutoff voltage for fixed Bo (in KV)is = 22.0 KV\n", "The Hull cutoff magnetic field density for fixed Vo(in mWb/m**2)is = 6.74 mWb/m2\n" ] } ], "prompt_number": 4 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg10.1.2a:pg-459" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#(a) Calculate the electron velocity at the hub surface\n", "em=1.759*(10**11) #em=e/m is the charge to mass ratio of electron\n", "Bo=0.015 #Magnetic flux density in Wb/m**2\n", "d=5*(10**-2) #Distance between cathode and anode in meter\n", "h=2.77*(10**-2) #hub thickness in meter\n", "V=em*Bo*h \n", "print\"The electron velocity at the hub surface(in m/s)is =\",\"{:.1e}\".format(V),\"m/s\" #answer in book is wrong\n", "\n", "#(b) Calculate the phase velocity for synchronism\n", "Vph=V #Vph=W/B and for synchronism Vph=V\n", "print\"The phase velocity for synchronism is Vph=w/B =\",\"{:.1e}\".format(Vph),\"m/s\" \n", "\n", "#(c) Calculate the Hartree anode voltage\n", "Vph=int(Vph/1000000) #converting the Vph in to the format printed above for easy calculations\n", "Vph=Vph*1000000\n", "Voh=((Vph*Bo*d))-((1.0/2)*(1/em)*(Vph**2)) \n", "Voh=Voh/1000 #in KV\n", "print\"The Hartree anode voltage (in KV) is =\",round(Voh,2),\"KV\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The electron velocity at the hub surface(in m/s)is = 7.3e+07 m/s\n", "The phase velocity for synchronism is Vph=w/B = 7.3e+07 m/s\n", "The Hartree anode voltage (in KV) is = 39.6 KV\n" ] } ], "prompt_number": 6 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg10.1.5:pg-465" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#(a) Calculate the cutoff voltage for fixed Bo\n", "em=1.759*(10**11) #em=e/m is the charge to mass ratio of electron\n", "Bo=0.01 #Magnetic flux density Wb/m**2\n", "a=3*(10**-2) #anode radius in meter\n", "b=4*(10**-2) #Cathode radius in meter\n", "Voc=(1.0/8)*(em)*(Bo**2)*(a**2)*((1-((b/a)**2))**2) \n", "Voc=Voc/1000 # in KV\n", "print\"The cutoff voltage for fixed Bo(in KV)is =\",round(Voc,2),\"KV\"\n", "\n", "#(b) Calculate the cutoff magnetic flux density for fixed Vo\n", "V0=10*(10**3) #Anode voltage in Volt\n", "Boc=(-1/(sqrt(em)))*(sqrt(8*V0))/((a)*(1-((b/a)**2))) \n", "print\"The cutoff magnetic flux density for fixed Vo(in Wb/m**2)is =\",round(Boc,4),\"Wb/m2\" " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The cutoff voltage for fixed Bo(in KV)is = 1.2 KV\n", "The cutoff magnetic flux density for fixed Vo(in Wb/m**2)is = 0.0289 Wb/m2\n" ] } ], "prompt_number": 7 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg10.1.6:pg-467" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#(a) Calculate the agile excursion\n", "t=0.2*(10**-6) #pulse duration in seconds\n", "N=14 #pulse rate on target per scan\n", "AC=N/t #agile Excursion\n", "AC=AC/(10**6) #in MHz\n", "print\"The agile excursion(in MHz)is =\",int(AC),\"MHz\"\n", "\n", "#(b) Calculate the pulse-to-pulse frequency separation\n", "fp=1.0/t \n", "fp=fp/(10**6) #in MHz\n", "print\"The pulse-to-pulse frequency separation(in MHz)is =\",int(fp),\"MHz\" \n", "\n", "#(c) Calculate the signal frequency\n", "DC=0.001 #Duty cycle\n", "f=(DC/t) \n", "f=f/(10**3) #in KHz\n", "print\"The signal frequency(in KHz)is =\",int(f),\"KHz\"\n", "\n", "#(d) Calculate the time for N pulses\n", "Time=N/f \n", "print\"The time for 14 pulses per second (in ms)is =\",Time,\"ms\" \n", "\n", "#(e) Calculate the agile rate\n", "Agile_rate=1/(2*Time*(10**-3)) \n", "print\"The agile rate(in Hz)is =\",round(Agile_rate,2),\"Hz\" " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The agile excursion(in MHz)is = 70 MHz\n", "The pulse-to-pulse frequency separation(in MHz)is = 5 MHz\n", "The signal frequency(in KHz)is = 5 KHz\n", "The time for 14 pulses per second (in ms)is = 2.8 ms\n", "The agile rate(in Hz)is = 178.57 Hz\n" ] } ], "prompt_number": 8 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg10.2.1:pg-473" ] }, { "cell_type": "code", "collapsed": false, "input": [ "#(a) Calculate the induced RF power\n", "Vao=2*(10**3) #Anode dc voltage in Volt\n", "Iao=1.5 #Anode dc current in ampere\n", "ne=0.20 #Electronic efficiency\n", "Pgen=Vao*Iao*ne \n", "print\"The induced RF power(in W)is =\",int(Pgen),\"W\" \n", "\n", "#(b) Calculate the total RF output power\n", "Pin=80 #RF input power in Watt\n", "Pout=Pin+(Pgen) \n", "print\"The total RF output power(in W)is =\",int(Pout),\"W\" \n", "\n", "#(c) Calculate the power gain\n", "g=Pout/Pin \n", "g=10*log10(g) #in decibels\n", "print\"The power gain(in dB)is =\",round(g,1),\"dB\" " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The induced RF power(in W)is = 600 W\n", "The total RF output power(in W)is = 680 W\n", "The power gain(in dB)is = 9.3 dB\n" ] } ], "prompt_number": 9 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg10.3.1:pg-478" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#(a) Calculate the dc electron-beam velocity\n", "V0=15*(10**3) #Anode voltage in Volt\n", "v0=0.593*(10**6)*sqrt(V0) #v0=sqrt((2*e*V0)/m),where e is the charge on electron and m is the mass of electron \n", " #sqrt(2*e/m)=0.593*(10**6)\n", "print\"The dc electron-beam velocity (in m/s)is =\",\"{:.3e}\".format(v0),\"m/s\" #answer in book is wrong\n", "\n", "#(b) Calculate the electron-beam phase constant\n", "f=8*(10**9) #operating frequency in Hertz\n", "w=2*math.pi*f #angular frequency in Hertz\n", "v0=int(v0/100000) #converting v0 in to the format printed above for easy calculations\n", "v0=v0*100000\n", "Be=w/v0 \n", "print\"The electron-beam phase constant(in rad/m)is =\",round(Be,2),\"rad/s\" \n", "\n", "#(c) Calculate the cyclotron angular frequency\n", "em=1.759*(10**11) #em=e/m is the charge to mass ratio of electron\n", "Bo=0.2 #Magnetic flux density in Wb/m**2\n", "wc=(em*Bo) \n", "print\"The cyclotron angular frequency(in rad/s)is =\",\"{:.3e}\".format(wc),\"rad/s\" \n", "\n", "#(d) Calculate the cyclotron phase constant\n", "Bm=wc/v0 \n", "print\"The cyclotron phase constant(in rad/m)is =\",round(Bm,2),\"rad/s\" \n", "\n", "#(e) Calculate the gain parameter\n", "Z0=50 #characteristic impedance in Ohms\n", "I0=3.0 #Anode current in ampere\n", "C=((I0*Z0)/(4*V0))**(1/3.0)\n", "print\"The gain parameter is =\",round(C,3) " ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The dc electron-beam velocity (in m/s)is = 7.263e+07 m/s\n", "The electron-beam phase constant(in rad/m)is = 692.36 rad/s\n", "The cyclotron angular frequency(in rad/s)is = 3.518e+10 rad/s\n", "The cyclotron phase constant(in rad/m)is = 484.57 rad/s\n", "The gain parameter is = 0.136\n" ] } ], "prompt_number": 10 }, { "cell_type": "heading", "level": 2, "metadata": {}, "source": [ "Eg10.4.1:pg-483" ] }, { "cell_type": "code", "collapsed": false, "input": [ "import math\n", "#(a)Calculate the dc electron velocity\n", "V0=20*(10**3) #Anode voltage in Volt\n", "v0=0.593*(10**6)*sqrt(V0) #v0=sqrt((2*e*V0)/m),where e is the charge on electron and m is the mass of electron \n", " #sqrt(2*e/m)=0.593*(10**6)\n", "print\"The dc electron velocity (in m/s)is =\",\"{:.3e}\".format(v0),\"m/s\" \n", "\n", "#(b) Calculate the electron-beam phase constant\n", "f=4*(10**9) #operating frequency in Hertz\n", "w=2*math.pi*f #angular frequency in Hertz\n", "Be=w/v0 \n", "print\"The electron-beam phase constant(in rad/m)is =\",int(round(Be)),\"rad/m\" \n", "\n", "#(c) Calculate the delta differentials\n", "b=0.5 #b factor\n", "print\"The Delta differentials are:\" \n", "s1=(1j)*((b-sqrt((b**2)+4))/2)\n", "s1=round(s1.imag,2)\n", "s1=0+1j*s1\n", "print\"s1=\",s1 \n", "s2=(1j)*((b+sqrt((b**2)+4))/2)\n", "s2=round(s2.imag,2)\n", "s2=0+1j*s2\n", "print\"s2=\",s2\n", "\n", "#(d)Calculate the propagation constants\n", "D=0.8 #D factor\n", "print\"The propagation constants are:\" \n", "r1=((1j)*(round(Be)+b))+(b*D*s1) \n", "r1=round(r1.imag,1)\n", "r1=0+1j*r1\n", "print\"r1=\",r1\n", "r2=((1j)*(round(Be)+b))+(b*D*s2) # in book the value of s2 is used with negative sign which is wrong\n", "r2=round(r2.imag,2)\n", "r2=0+1j*r2\n", "print\"r2=\",r2 \n", "\n", "#(e)Calculate the oscillation condition\n", "print\"The oscillation occurs at DN=1.25 for n=1\" \n", "N=1.25/D \n", "print\"then N=\",N \n", "l=(2*math.pi*N)/round(Be) \n", "l=l*100 #in cm\n", "print\"and l= 2*pi*N/Be(in cm) =\",round(l,2),\"cm\"" ], "language": "python", "metadata": {}, "outputs": [ { "output_type": "stream", "stream": "stdout", "text": [ "The dc electron velocity (in m/s)is = 8.386e+07 m/s\n", "The electron-beam phase constant(in rad/m)is = 300 rad/m\n", "The Delta differentials are:\n", "s1= -0.78j\n", "s2= 1.28j\n", "The propagation constants are:\n", "r1= 300.2j\n", "r2= 301.01j\n", "The oscillation occurs at DN=1.25 for n=1\n", "then N= 1.5625\n", "and l= 2*pi*N/Be(in cm) = 3.27 cm\n" ] } ], "prompt_number": 11 } ], "metadata": {} } ] }