from math import log fm=input("Enter the band limited freq in hertz is ") Rn=2*fm# # Nyquist sampling rate Ra=Rn*(4/3)## actual Nyquist sampling rate # here the maximum quantization error(E) is 0.5% of the peak amplitide mp. Hence, E=mp/L=0.5*mp/100*L mp=1##we assume peak amplitude is unity L=(mp*100)/(0.5*mp)# for i in range(0,11): j=2**i if(j>=L): L1=j# break# n=log(L1,2)## bits per sample c=n*Ra## total no of bits transmitted # Beause we can transmit up to 2bits/per hertz of bandwidth,we require minimum transmission bandwidth Bt=c/2 Bt=c/2# print "minimum transmission bandwidth = %.2f Hertz"%Bt s=input("enter the no of signal to be multiplexed ") Cm=s*c##total no of bits of 's' signal c1=Cm/2## minimum transmission bandwidth print "minimum transmission bandwidth = %.2f Hertz"%c1
Enter the band limited freq in hertz is 1100 minimum transmission bandwidth = 8800.00 Hertz enter the no of signal to be multiplexed 25 minimum transmission bandwidth = 220000.00 Hertz
from math import log,log10 # from the expresion given on the page no 272# (So/No)=(a+6n) dB where a=10log[3/[ln(1+u)]**2] #check the ollowing code for L=64 and L=256 L=input("enter the value of L = ") B=input("enter the bandwidth of signal in hertz : ") n=log(L,2)# Bt=n*B# u=100##given a=10*log10(3/(log(1+u))**2) SNR=(a+(6*n))# print "SNR ratio is = %0.2f "%SNR # Here the SNR ratio for the two cases are found out. The difference between the two SNRs is 12dB which is the ratio of 16. Thus the SNR for L=256 is 16 times the SNR for L=64. The former requires just about 33% more bandwidth compared to the later.
enter the value of L = 12 enter the bandwidth of signal in hertz350 SNR ratio is = 13.00