# Chapter 1:Introduction to Radar, Radar Parameters and their Definitions¶

## Example 1, Page No:34¶

In [6]:
import math

#variable declaration
PRF= 1000;           #pulse repetitive frequency in Hz
PW = 2*10**-6;         #pulse width 2us
Pav=100;              #average power in watts

#Calculations

Ppeak = (Pav)/float((PW*PRF));         #Peak power in watts
D     = Pav/float(Ppeak);             #Duty cycle

#result
print' Peak power is ',Ppeak/1000,' KW';
print' Duty cycle is %3.1e'%D;

 Peak power is  50.0  KW
Duty cycle is 2.0e-03


## Example 2, Page No:35¶

In [5]:
import math

#variable declaration
PRF           = 1.2*10**3;                 #pulse repetitive frequency in Hz
PI            = 0.6*10**-3;                #pulse interval in sec

#Calculations

PRT            = 1/float(PRF);                     #pulse repetition frequency in Hz
PW             = PRT-PI;                    #pulse width in sec;

#result
print'Pulse repetitive time is %2.3g'%(PRT*1000),'ms';
print'Pulse width is %2.3g'%(PW*1000),'ms';

Pulse repetitive time is 0.833 ms
Pulse width is 0.233 ms


## Example 3,Page No:35¶

In [10]:
import math

#variable declaration
D           = float(0.001);              #Duty Cycle
Ppeak       =500*10**3;           #Peak Power in Watts

#Calculations

Pav          = D * Ppeak;                  # D=averagepower/Peakpower;

#result
print'Average power is %g'%Pav,' Watts';

Average power is 500  Watts


## Example 4:Page No:35¶

In [4]:
import math

#variable declaration

PRF          = 1000;              # pulse repetitive frequency in Hz
Ppeak        = 10*10**6;          # peak power in watts
Pav          = 100*10**3;         # average power in watts

#Calculations

D     = Pav/float(Ppeak);          #Duty cycle
PRT   = 1/float(PRF);              #pulse repetitive time;

#result

print'Duty cycle is %g'%D;
print'Repetitive time is %g'%(PRT*1000),'ms';

Duty cycle is 0.01
Repetitive time is 1 ms


## Example 5, Page No:36¶

In [15]:
import math

#variable declaration
F      = 6*10**9;              #frequency in Hz
Vo     = 3*10**8;              #velocity in m/s;
Vr     = 200;                 #Radial velocity in kmph

#Calculations

lamda   = Vo/float(F);                        #wavelength = vel/freq;
Fd      = (2*Vr/float(lamda))*(5/float(18));         #doppler frequency in Hz

#5/18 is multiplied to convert kmph to m/s

#result
print'Doppler Frequency is %3.3g'%(Fd/1000),'KHz';

Doppler Frequency is 2.22 KHz