[Discuss-gnuradio] Multiple-Transmitter OFDM

[Ramazan Çetin]

Hello all,

I have implemented OFDM system that has one receiver and two 
transmitters. Receiver can receive signals correctly, when one of the 
transmitters is active. However, when both of them are active, receiver 
cannot receive all the packets. They are interfering each other.

To overcome this situation, i tried to allocate different carriers to 
transmitters. For example; in 256 carriers OFDM system, 1 to 120 is for 
transmitter 1 and -120 to -1 is for transmitter 2. In this situation, 
receiver cannot still receive entire packets, when both of them are active.

At the end, i decided to give some gap between transmitters. So, 36 to 
90 and -36 to -90 are assigned to transmitters. But, result is same. I 
have attached two pictures of spectrum. They represents state of one and 
two transmitters are active. You can check the situation from there.


So, can you suggest a way to receive from two transmitters without 
interference?

Best regards.

Ramazan

s2.jpeg
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s1.jpeg
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