I have a friend working in wireless communications research. He told me that we can transmit more than one symbol in a given slot using one frequency (of course we can decode them at the receiver).

The technique as he said uses a new modulation scheme. Therefore if one transmitting node transmits to one receiving node over a wireless channel and using one antenna at each node, the technique can transmit two symbols at one slot over one frequency.

I am not asking about this technique and I do not know whether it is correct or not but I want to know if one can do this or not? Is this even possible? Can the Shannon limit be broken? Can we prove the impossibility of such technique mathematically?

Other thing I want to know, if this technique is correct what are the consequences? For example what would such technique imply for the famous open problem of the interference channel?

Please cite references, if possible.

  • Please do not cross post. Also, to keep the question from becoming an off-topic poll, I am taking the liberty of editing out the portion of the question that's too broad.
    – This
    Mar 24 '14 at 17:50
  • I did not know that. So I asked multiple time the same question. Sorry.
    – Learning
    Mar 24 '14 at 18:16

No, we can't.

What we can do, with better modulation, is approach the shannon limit more closely. Otherwise, if you need more bandwidth (in megabits), either increase the bandwidth (in (mega)Hertz), or increase the signal/lower the nose to get better SNR.

  • 1
    Or increase the number of mediums (think beamforming, MIMO and such).
    – BatchyX
    Mar 25 '14 at 16:29
  • Of course.. but for one medium/information channel, shannon is still a limit.
    – mulaz
    Mar 25 '14 at 16:30

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.