I wanted to simulate OFDM system in MATLAB. I'm using Fixed WiMAX OFDM parameters in my simulation, where the number of data sub-carriers are 192, number of Pilot sub-carriers are 8, number Null sub-carriers are 56. Null tones can be obtained in MATLAB by generating zero matrix with the required rows and columns.
% Null subcarrier: msg(1,1:100)=0;
similarly, for data subcarriers, digitally modulated data is sent.
% Data subcarrier: msg(2,1:100)= 1*sign(randn(1,100)) + i*sign(randn(1,100));
my question is, what type of data could I send for Pilot tones?? all books and literature I have read says that: Pilot tones are just known data. What type of Known data are the Pilot tones? What kind of data should I send in my specific problem? Please, clarify.