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
1 % MATLAB script for Illustrative Problem 8.1 2 3 M = 50; 4 m = 0:M-1; 5 phi_k = 2*pi*rand; 6 phi_j = 2*pi*rand;
7 % The sampled signals: 8 x_k = sin(4*pi*m/5+phi_k);
9 n = 1; 10 x_j_1 = sin(4*pi*m/5+2*pi*m*n/M+phi_j); 11 n = 2 ; 12 x_j_2 = sin(4*pi*m/5+2*pi*m*n/M+phi_j); 13 n = 3 ; 14 x_j_3 = sin(4*pi*m/5+2*pi*m*n/M+phi_j);
15 % Investigating the orthogonality of the sampled signals: 16 Sum1 = sum(x_k.*x_j_1); 17 % Displaying the results: 18 disp(['The result of the computation for n=1 is: ',num2str(Sum1)]) 19 Sum2 = sum(x_k.*x_j_2); 20 disp(['The result of the computation for n=2 is: ',num2str(Sum2)]) 21 Sum3 = sum(x_k.*x_j_3); 22 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