Chapter 21 : Cellular Radio

Example 1 : pg 795

 
# page no 795
# prob no 21.1
#calculate the hand off time
#given
v=100.;#in km/hr
# first convert speed into m/sec
v1=(100.*10**3)/3600;#in km/sec
#calculations and results
#part a)
r=10.**4;#in m
t=(2*r)/v1;
print 'Handoff time is',t,'sec'
#part b)
r=500;#in m
t=(2*r)/v1;
print 'Handoff time is',t,'sec'

Handoff time is 720.0 sec
Handoff time is 36.0 sec

Example 2 : pg 807

 
# page no 807
# prob no 21.2
#calculate the average and peak traffic
#given
N = 12
m = 120.
a = 20000.
th = 30.#in min/day this means
H = 0.5
tp = 10.
#calculations and results
#part a)Calculation of the average and peak traffic in erlangs for the whole
#system
# The average traffic is
T = a * H / 24
print 'a) The average traffic is',round(T,3),'E'
# The peak traffic is
T1 = (a * tp) / 60
print 'The peak traffic is',round(T1,3),'E'
#part b)Calculation of the average and peak traffic in erlangs for one cell
# The average traffic per cell is
t = T / m
print 'b) The average traffic per cell is',round(t,3),'E'
# The peak traffic per cell is
t = T1 / m
print 'The peak traffic per cell is',round(t,3),'E'
# part c)
# For average traffic at 3.47E, the blocking probability is much less than 1%,
# since the average no of call is much less than the no of channels. 
#However, the blocking probability increases to just over 5%

a) The average traffic is 416.667 E
The peak traffic is 3333.333 E
b) The average traffic per cell is 3.472 E
The peak traffic per cell is 27.778 E

Example 3 : pg 816

 
# page no 816
# prob no 21.3
#calculate the max distance
#given
tg=123.*10**-6;
c=3.*10**8;
#calculations
#The maximum distance between base and mobile is
d=c*tg;
#results
print 'The maximum distance between base and mobile is',d,'m'

The maximum distance between base and mobile is 36900.0 m