Re: [Discuss-gnuradio] building carrier sense in the FPGA and UHD

[Andre Puschmann]

On 03/04/2012 04:01 PM, Marcus D. Leech wrote:
>> George,
>>
>> I do think we need something like what you have suggested but I am still
>> a bit puzzled about the right way of implementing it.
>>
>> Best regards,
>> Andre
>>
> I think a more fundamental issue is that "carrier sense" isn't actually
> defined in any kind of general way.  Certainly for *some* types of
>   PHYs, you can do simple energy-presence detection.  But usually, it's
> more complicated than that, and it varies widely from PHY to
>   PHY.  In some, you'll need to run a correlator before you even know
> whether the channel is busy or not.  In others, simple energy
>   detection works.
> 
> I don't think there's a general-purpose way of doing this, but that's
> just my POV.

You're absolutely right, Marcus. I also think it'd be quite difficult to
find a truly general-purpose solution to that.

Knowing George's field of interested, I was assuming something like a
simple energy detector. I think even this simple example shows the
difficulties quite clearly.

-Andre