From mboxrd@z Thu Jan 1 00:00:00 1970 From: Oleksij Rempel Subject: Re: Standardisation - adding 2 bit STBC and Ness to MCS Date: Wed, 01 May 2013 16:34:21 +0200 Message-ID: <518127ED.9060900__40512.8046324991$1367418879$gmane$org@rempel-privat.de> Mime-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: quoted-printable Return-path: Sender: radiotap-owner-sUITvd46vNxg9hUCZPvPmw@public.gmane.org To: radiotap-qavaossjCcEdnm+yROfE0A@public.gmane.org, simon-vp0mx6+5gkqFX2APIN6yfw@public.gmane.org, johannes-cdvu00un1VgdHxzADdlk8Q@public.gmane.org, Adrian Chadd Cc: "ath9k-devel-xDcbHBWguxHbcTqmT+pZeQ@public.gmane.org" , linux-wireless-u79uwXL29TY76Z2rM5mHXA@public.gmane.org List-Id: radiotap@radiotap.org Hallo all, > http://www.radiotap.org/suggested-fields/MCS%20extension%20for%20STBC%2= 0and%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=20 docs, i assume that: - STBC is done by sending, at least, two stream with same data in=20 different order. - It means for me, that real use of STBC can be made only on MIMO hardwar= e. - If 1x1 receiver indicates that it got STBC encoded frame, it dos not=20 meant, it would be able to use redundant data from second stream. - There are fallowing STBC schemes: Alamouti=E2=80=99s STBC for 2 transmit antennas and orthogonal STBC for 3 and 4 transmit=20 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=20 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=E2=80=99s schema with 2 streams. Most= ly used=20 method. - RX-STBC123 - is orthogonal schema and not widely used method. Since=20 last method use wide spectrum to transmit data comparable to SISO=20 stream, it makes almost no sense. But 3-stream method get optimal error=20 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" --=20 Regards, Oleksij