Re: [Discuss-gnuradio] How to detect collision when two packets are transmitted simultaneously from two transmitters.

[Martin Braun (CEL)]

On Mon, Nov 11, 2013 at 03:14:04PM +0530, Sumedha Goyal wrote:
> Hello Aditya,
> 
> 1. I tried checking for the average power but that doesn't work. Even with two
> transmitters transmitting at the same time the energy detected by the receiver
> doesn't change much. It remains in the same order.
> 2. Is there any other simpler way of detecting collisions other than the
> mentioned paper?

Sumedha,

this problem is a very fundamental one, and there is no one single
correct answer. Using power as a metric is tricky, as in practice, you
never know the initial power levels of the inidivual received signals.

And if you had a test, how could you be sure it correctly identified a
collision, and you didn't simply lose a packet due to a bad wave
propagation situation?

Perhaps you should try and tackle this on the MAC layer. When there is a
collision, you will receive neither packet correctly, perhaps that will
trigger an ARQ etc. You can allocate slots to users, or something like
that.

MB

-- 
Karlsruhe Institute of Technology (KIT)
Communications Engineering Lab (CEL)

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