hi all,
i am doing my final project on the above topic..i need a matlab code for one transmitter, relay and receiver with decode and forward and also the receiver should have feedback to the transmitter regarding the data received.. the modulation used should be chosen based on the channel strength..for example BPSK if the channel is noisy as it is robust.. can anybody help me pls??? its urgent...

i have uploaded the network model too.. in that Receiver 4 and receiver 2 should acts as relay while the transmitter sends information to receiver 3. Based on the modulation coding scheme the relays are selected..

Thanks in advance

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