CCS - Multicarrier Modulation and OFDM

 

Multicarrier Modulation and OFDM

In this chapter, we describe the transmission of digital information on multiple
carriers. In multicarrier modulation, the available channel bandwidth is subdivided into
a number of equal-bandwidth subchannels,

 

 

 

 

 

 

 

Matlab Coding

 

 

% MATLAB script for Illustrative Problem 8.1

M = 50;
m = 0:M-1;
phi_k = 2*pi*rand;
phi_j = 2*pi*rand;

% The sampled signals:
x_k = sin(4*pi*m/5+phi_k);

n = 1;
x_j_1 = sin(4*pi*m/5+2*pi*m*n/M+phi_j);
n = 2 ;
x_j_2 = sin(4*pi*m/5+2*pi*m*n/M+phi_j);
n = 3 ;
x_j_3 = sin(4*pi*m/5+2*pi*m*n/M+phi_j);

% Investigating the orthogonality of the sampled signals:
Sum1 = sum(x_k.*x_j_1);
% Displaying the results:
disp(['The result of the computation for n=1 is:    ',num2str(Sum1)])
Sum2 = sum(x_k.*x_j_2);
disp(['The result of the computation for n=2 is:    ',num2str(Sum2)])
Sum3 = sum(x_k.*x_j_3);
disp(['The result of the computation for n=3 is:    ',num2str(Sum3)])


Outputs

The result of the computation for n=1 is: -4.3743e-14

The result of the computation for n=2 is: 5.6066e-15

The result of the computation for n=3 is: -2.9976e-14

 

Reference,

　　1. <<Contemporary Communication System using MATLAB>> - John G. Proakis