Hi,
Thank you all for your replies.
*Correction about first post: I'm using the FFT block as an IFFT. As per OFDM design, the receiver contains an IFFT.
orchestradirector:
I don't understand what you mean when you say that I can transmit 1 and 0 values to the IFFT. In this case, where does the QPSK "constellation mapping" come in?
kaz: I do I/Q mapping (QPSK). I mapped two bits into a symbol using QPSK. I and Q for each channel get the real and imaginary value. Based on my scenario, I have the following data after I/Q mapping:
Channel 1 I: +0.7071
Channel 1 Q: +0.7071
Channel 2 I: -0.7071
Channel 2 Q: -0.7071
Channel 3 I: +0.7071
Channel 3 Q: -0.7071
Channel 4 I: +0.7071
Channel 4 Q: +0.7071
My overall question is: Based on my scenario, how do I input the data into the IFFT (Altera FFT Block) and what would the data look like?