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* Re: Standardisation - adding 2 bit STBC and Ness to MCS
@ 2013-05-01 14:34 Oleksij Rempel
  0 siblings, 0 replies; 10+ messages in thread
From: Oleksij Rempel @ 2013-05-01 14:34 UTC (permalink / raw)
  To: radiotap-qavaossjCcEdnm+yROfE0A, simon-vp0mx6+5gkqFX2APIN6yfw,
	johannes-cdvu00un1VgdHxzADdlk8Q, Adrian Chadd
  Cc: ath9k-devel-xDcbHBWguxHbcTqmT+pZeQ,
	linux-wireless-u79uwXL29TY76Z2rM5mHXA

Hallo all,


> http://www.radiotap.org/suggested-fields/MCS%20extension%20for%20STBC%20and%20Ness
>
> I have posted 3 patches on the proposal page (see Attachments):
>
> 1. A patch that applies to the Linux kernel v3.7-rc1 to collect the new
> STBC and Ness parameters from a wireless driver, and add them into the
> MCS radiotap field.
> 2. A patch to the Intel wireless driver in the kernel to collect STBC
> and Ness information.
> 3. A patch to wireshark to display STBC and Ness information.
>
> With this I believe we have everything needed to start the 3 week
> comment period.

There is a bit more then 3 week now. I would like to have this approved :)
Are there any thing needed to finish this?

Beside, i have one question about how STBC work. According to differnet 
docs, i assume that:
- STBC is done by sending, at least, two stream with same data in 
different order.
- It means for me, that real use of STBC can be made only on MIMO hardware.
- If 1x1 receiver indicates that it got STBC encoded frame, it dos not 
meant, it would be able to use redundant data from second stream.
- There are fallowing STBC schemes: Alamouti’s
STBC for 2 transmit antennas and orthogonal STBC for 3 and 4 transmit 
antennas.

According to this information, what do we call 1,2 or 3 stream STBC?
Since STBC should have minimal 2 stream, but in same time we have 1x1 
and 2x2 hardware which able to receive and decode STBC stream i assume:
	- RX-STBC1 is for compatibility only. No data redundancy.
	- RX-STBC12 - can be used Alamouti’s schema with 2 streams. Mostly used 
method.
	- RX-STBC123 - is orthogonal schema and not widely used method. Since 
last method use wide spectrum to transmit data comparable to SISO 
stream, it makes almost no sense. But 3-stream method get optimal error 
corect in compare with 2 and 4 strea schemas.

Do this assumptions correct?

PS: My assumptions based on "MIMO Space-Time Block Coding (STBC):
Simulations and Results"
-- 
Regards,
Oleksij

^ permalink raw reply	[flat|nested] 10+ messages in thread
[parent not found: <518127ED.9060900@rempel-privat.de>]
* MCS field - STBC and Ness
@ 2012-05-11  0:31 Simon Barber
  2012-05-11  7:04 ` Wojciech Dubowik
  0 siblings, 1 reply; 10+ messages in thread
From: Simon Barber @ 2012-05-11  0:31 UTC (permalink / raw)
  To: radiotap-sUITvd46vNxg9hUCZPvPmw, wojciech.dubowik-ASv44eHyqLVBDgjK7y7TUQ

Hi all,

I am writing a Wireshark extension to visualise 802.11 frames on a 
timeline. In order to do this I need to be able to calculate the 
duration from start of TX to end of TX for each frame.

For 802.11n I need to know the number of HT-DLTF and HT-ELTF training 
symbols that are sent in the header - I have everything else needed to 
calculate the duration. Given the MCS and the STBC and the Ness (Number 
of extension spatial streams) I can calculate the number of training 
symbols.

Both STBC and Ness are encoded in the HT-SIG transmitted at the start of 
each HT frame.

The current proposal (or has it not yet been accepted?) for STBC 
allocates just 1 bit - but the STBC field can have values or 0, 1 or 2.

Ness can be 0-3, so the remaining 2 bits could be allocated to Ness, but 
this does not solve the problem of how to encode the modes with 2 
spatial streams and 2 additional streams for STBC.

Does anyone know what current hardware supports - STBC values or 0,1,2? 
Ness values of 0-3?

Any suggestions for how to convey these

Simon

^ permalink raw reply	[flat|nested] 10+ messages in thread

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2013-05-01 14:34 Standardisation - adding 2 bit STBC and Ness to MCS Oleksij Rempel
     [not found] <518127ED.9060900@rempel-privat.de>
     [not found] ` <518127ED.9060900-YEK0n+YFykbzxQdaRaTXBw@public.gmane.org>
2013-05-02 20:44   ` Johannes Berg
2013-05-03 21:12   ` Simon Barber
     [not found] ` <1367527479.11375.19.camel@jlt4.sipsolutions.net>
     [not found]   ` <1367527479.11375.19.camel-8Nb76shvtaUJvtFkdXX2HixXY32XiHfO@public.gmane.org>
2013-05-07  7:40     ` Oleksij Rempel
     [not found]   ` <5188AFFE.6070804@rempel-privat.de>
     [not found]     ` <5188AFFE.6070804-YEK0n+YFykbzxQdaRaTXBw@public.gmane.org>
2013-05-07 13:54       ` Johannes Berg
     [not found]     ` <1367934867.8328.31.camel@jlt4.sipsolutions.net>
     [not found]       ` <1367934867.8328.31.camel-8Nb76shvtaUJvtFkdXX2HixXY32XiHfO@public.gmane.org>
2013-05-07 13:55         ` Johannes Berg
     [not found]       ` <1367934904.8328.32.camel@jlt4.sipsolutions.net>
     [not found]         ` <1367934904.8328.32.camel-8Nb76shvtaUJvtFkdXX2HixXY32XiHfO@public.gmane.org>
2013-05-07 14:25           ` Oleksij Rempel
     [not found]         ` <518916D1.4070902@gmail.com>
     [not found]           ` <518916D1.4070902-Re5JQEeQqe8AvxtiuMwx3w@public.gmane.org>
2013-05-07 15:03             ` Oleksij Rempel
     [not found]           ` <518917C4.9090607@rempel-privat.de>
     [not found]             ` <518917C4.9090607-YEK0n+YFykbzxQdaRaTXBw@public.gmane.org>
2013-05-07 16:09               ` Jonathan Bither
  -- strict thread matches above, loose matches on Subject: below --
2012-05-11  0:31 MCS field - STBC and Ness Simon Barber
2012-05-11  7:04 ` Wojciech Dubowik
2012-05-11 16:44   ` Simon Barber
2012-05-11 16:53     ` Simon Barber
2012-05-11 18:35       ` Johannes Berg
2012-05-12  4:27         ` Simon Barber
2012-07-05  9:12           ` Johannes Berg
2012-11-01  0:22             ` Simon Barber
2012-11-02  0:24               ` Simon Barber
     [not found]                 ` <509312DB.7070100-vp0mx6+5gkqFX2APIN6yfw@public.gmane.org>
2012-11-17  6:32                   ` Standardisation - adding 2 bit STBC and Ness to MCS Simon Barber

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