[Discuss-gnuradio] OFDM Blocks

Hello,

I'm working with USRP OFDM blocks. I'm confused about how to use built-in OFDM Transmitter and OFDM Receiver blocks. 

1. How to set the fields- occupied carriers, pilot carriers, sync word and pilot symbols?

2. I'm using N200 board. I transmitted signal using OFDM Mod block UHD Sink block. It seems it       transmits properly. But when I receive the signal using OFDM Demod and UHD Source block then it   looks the signal is not received properly. The received signal shows a quite different pattern than the transmit one. It looks it receives something different signal, not the transmitted one. Note: I'm using same USRP board to transmit and receive signal simultaneously.

3. Again, I need to control the frequency offset of the subcarriers. How can I do that using the built-in blocks? 

4. And is there any way to control the transmit signal power? 

5. Well, does the OFDM Mod2 block works? If it is then how to use that one?

I already asked a lot of questions. Thanks for your patience.

Regads

Nashid Anjum

Graduate Student

South Dakota School of Mines and Technology