Chapter 1 - PULSE FUNDAMENTALS

Example E1 - Pg 9

In [1]:
#Caption:Find (a)Pulse amplitude (b)PRF (c)PW (d)Duty cycle and (e)M/S ratio
v=1.#Vertical scale(Volt per division)
h=0.1#Horizontal scale(Milli sec per division)
pv=3.5#Amplitude of pulse in divisions
t=6.#Time in divisions
pw=2.5#Width of pulse
P=pv*v
print '%s %.1f' %('(a)Pulse Amplitude (in volts)=',P)
T=t*h
prf=(1/T)*1000
print '%s %.f' %('(b)PRF(in pps)=',prf)
p=pw*h
print '%s %.2f' %('(c)PW (in ms)=',p)
sw=pv*h
d=(p/T)*100
print '%s %.1f' %('(d)Duty cycle(in %)=',d)
m=p/sw
print '%s %.2f' %('(e)M/S ratio=',m)

(a)Pulse Amplitude (in volts)= 3.5
(b)PRF(in pps)= 1667
(c)PW (in ms)= 0.25
(d)Duty cycle(in %)= 41.7
(e)M/S ratio= 0.71

Example E2 - Pg 12

In [3]:
#Caption:Determine (a)Pulse amplitude,tilt,rise time,fall time,PW,PRF,mark to space ratio,and duty cycle (b)tilt
vs=100.#Vertical scale(in mv/divisions)
hs=100.#Horizontal scale(in micro sec/division)
e1=380.#first peak of waveform(in mv)
e2=350.#second peak of waveform(in mv)
E=(e1+e2)/2.
t=(e1-e2)*100./E
tr=0.3*hs
tf=0.4*hs
T=5.*hs
prf=10.**6./T
pw=2.2*hs
sw=2.8*hs
ms=pw/sw
dc=(pw*100.)/T
print '%s %.f'%('(a)Pulse Amplitude(in mv)=',E)
print '%s %.1f'%('(a)tilt(in %)',t)
print '%s %.f'%('(a)rise time(in micro sec)=',tr)
print '%s %.f'%('(a)fall time(in micro sec)=',tf)
print '%s %.f'%('(a)PW(in micro sec)=',pw)
print '%s %.f'%('(a)PRF(in pps)=',prf)
print '%s %.2f'%('(a)M/s ratio=',ms)
print '%s %.f' %('(a)Duty cycle(in %)=',dc)
eb=0.5*vs
ee=2.25*vs
tb=eb*100./ee
print '%s %.1f' %('(b)Tilt(in %)=',tb)

(a)Pulse Amplitude(in mv)= 365
(a)tilt(in %) 8.2
(a)rise time(in micro sec)= 30
(a)fall time(in micro sec)= 40
(a)PW(in micro sec)= 220
(a)PRF(in pps)= 2000
(a)M/s ratio= 0.79
(a)Duty cycle(in %)= 44
(b)Tilt(in %)= 22.2

Example E3 - Pg 15

In [3]:
#Caption:Determine average voltage level
vs=2.#Vertical scale(V/div)
hs=1.#Horizontal scale(ms/div)
v1=8.#Amplitude of signal in (+)ve direction (in volts)
v2=-1.#Amplitude of signal in (-)ve direction (in volts)
t1=0.8#Horizontal divisions for v1
t2=2.2#Horizontal divisions for v2
T=3.*hs
T1=t1*hs
T2=t2*hs
Va=((T1*v1)+(T2*v2))/T
print '%s %.1f' %('Average voltage (in volts)=',Va)

Average voltage (in volts)= 1.4

Example E4 - Pg 20

In [4]:
#Caption:Determine the upper 3db frequency of the amplifier
tr=1.#Rise time(in micro sec)
fu=0.35*10**3/tr
print '%s %.f' %('The upper 3db frequency of the amplifier(in khertz)=',fu)

The upper 3db frequency of the amplifier(in khertz)= 350

Example E5 - Pg 21

In [14]:
#Caption:Determine (a)Minimum upper cut frequency (b)Minimum pulse width and duty cycle
prf=1.5#in Khz
dc=3.#Duty cycle(in %)
pa=1.5#Amplitude of pulse(in Khz)
fu=1.#High frequency limit(in Mhz)
tr=10.#Rise time(in %)
pw=(dc/100.)*10.**6./pa
Tr=(tr/100.)*pw
fh=0.35*10.**6./Tr
print '%s %.f' %('(a)Minimum upper cut frequency(in hertz)=',fh)
Tr2=0.35*10.**(-6.)/fu
Pw=10.*Tr2
dc=Pw*100.*(pa*1000.)
print '%s %.7f' %('(b)Pulse width(in sec)=',Pw)
print '%s %.1f' %('(b)Duty cycle(in %)=',dc)

(a)Minimum upper cut frequency(in hertz)= 175
(b)Pulse width(in sec) and Duty cycle(in %)= 0.0000035
(b)Duty cycle(in %)= 0.5

Example E6 - Pg 22

In [16]:
#Caption:Calculate (a)Rise time in output waveform (b)Minimum upper cut off frequency and print '%s %.2f' %layed rise time
import math
tr=10.#Rise time of input waveform(in micro sec)
fu=350.#Upper cut off frequency(in KHz)
ti=100.#Input rise time(in ns)
trc=0.35*(10.**(-3.))/350.
tro=math.sqrt(((tr)*(10.**(-6.)))**2.+(trc**2.))*10.**6.
print '%s %.2f' %('(a)Rise Time(in Micro sec)=',tro)
tc=ti*(10.**(-9.))/3.
fh=0.35*10.**(-6.)/tc
Tro=math.sqrt((ti*(10.**(-9.)))**2.+(tc**2.))*10.**9.
print '%s %.1f' %('(b)Minimum upper cut off frequency(in Mhz)=',fh)
print '%s %.f' %('(b)rise time(in ns)=',Tro)

(a)Rise Time(in Micro sec)= 10.05
(b)Minimum upper cut off frequency(in Mhz)= 10.5
(b)rise time(in ns)= 105

Example E7 - Pg 23

In [17]:
#Caption:Calculate lowest input frequency 
import math
fl=10.#Lower cutoff frequency(in hertz)
t=0.02#Tilt on output waveform
f=math.pi*fl/(t*1000)
print '%s %.2f' %('Lowest input frequency(in Khz)=',f)

Lowest input frequency(in Khz)= 1.57

Example E8 - Pg 23

In [19]:
#Caption:Determine (a)upper cutoff frequency (b)lower cutoff frequency
import math
f=1.#frequency of square wave(in khz)
tr=200.#rise time of output(in ns)
t=0.03#fractional tilt
fh=0.35*10.**3./tr
print '%s %.2f' %('(a)upper cutoff frequency(in MHz)=',fh) 
fl=f*t*1000./math.pi
print '%s %.1f' %('(b)Lower cutoff frequency(in Hz)=',fl)

(a)upper cutoff frequency(in MHz)= 1.75
(b)Lower cutoff frequency(in Hz)= 9.5

Example E9 - Pg 24

In [21]:
#Caption:Determine upper and lower Frequencies
import math
tr=30.#Rise time(in micro sec)
PRF=2000.#Pulse repetition Frequency(in pps)
t=0.082#Tilt(in %)
Pw=220.#Pulse width(in micro sec)
fh=0.35*10.**(3.)/tr
fl=t*10.**6./(2.*math.pi*Pw)
print '%s %.2f' %('Upper frequency(in kHz)=',fh)
print '%s %.1f' %('lower frequency(in Hz)=',fl)

Upper frequency(in kHz)= 11.67
lower frequency(in Hz)= 59.3