Please, stay on the list. On 04 Oct 2014, at 18:20, Ernest Szczepaniak <ernest_szczepan...@wp.pl> wrote:
> Hi, > > we are talking about 'frame.bin' signal right? yes > Becouse my decoder says: > > Service: 'ok' > Protocol_version: 'Supported' > Type: 'Menagement' > Subtype: 'Probe Request' > To_DS: 'True' > From_DS: 'False' > More_fragments: 'No' > Power_menagement: 'Power-Saving Mode' > More_data: 'No' > Protected: 'No' > Order: 'Random' > > and the initial state was 0b0101011. Furthermore, i cant see those "1", which > will indicate the broadcast adress thou:( So i think it is not working > correctly yet. If you are still not convinced, you can very easily send the frame with a USRP and receive it with a WiFi card to inspect the MAC header with Wireshark. You can either use a simple GNU Radio flow graph (file source -> USRP sink) or use the tx_samples_from_file example that ships with UHD. At least my card agreed with my interpretation of the payload :-) Best, Bastian > > W dniu 2014-10-04 19:56, Bastian Bloessl pisze: >> Hi, >> >> On 04 Oct 2014, at 15:50, Ernest Szczepaniak <ernest_szczepan...@wp.pl> >> wrote: >> >>> Hello, >>> >>> First of all, much love for your reply (it made my day). >>> >>> So i started with sent frame [2]. And my receiver gives some nice results: >>> >>> - found OFDM symbol >>> - aquired time synchronization >>> - Shmidl/Cox says that there is no frequency offset (so it is good for no >>> noise frame) >>> - SIGNAL field is modulated with BPSK 6 Mbps (correct) and it says that: >>> - rest of the data is modulated with BPSK 6Mbps >>> - coderate is 1/2 >>> - 1 bit per carrier >>> - 364 octets of data (is that correct?) >>> - reserved field, parity bit and tail bits seems to be fine. >>> >>> Further MAC decoding says that: >>> - descrambler initial state is [0 1 0 1 0 1 1] (correct?) >>> - 16 zeros in SERVICE field (7 for desrcambler synchro and 9 reserved - >>> seems to be correct) >>> - according to standard this is a PNC Selection (PNCS) frame type with >>> retry ([0 0 0 1] in frame type field) is that correct? >> >> my decoder says: >> >> new mac frame (length 360) >> ========================================= >> duration: 00 00 >> frame control: 00 08 (DATA) >> Subtype: Data >> seq nr: 0 >> mac 1: ff:ff:ff:ff:ff:ff >> mac 2: 23:23:23:23:23:23 >> mac 3: ff:ff:ff:ff:ff:ff >> Hello World!Hello World!Hello World!Hello World!Hello World!Hello >> World!Hello World!Hello World!Hello World!Hello World!Hello World!Hello >> World!Hello World!Hello World!Hello World!Hello World!Hello World!Hello >> World!Hello World!Hello World!Hello World!Hello World!Hello World!Hello >> World!Hello World!Hello World!Hello World!Hello World! >> >> It does not contain a LLC, just a MAC header. It is BPSK 1/2 encoded. I >> guess the initial scrambler state was 0b0101010 (=42) and it is a data frame. >> >> Best, >> Bastian >> >> >>> Best, >>> >>> Ernest >>> >>> >>> >>> W dniu 2014-10-04 11:16, Bastian Bloessl pisze: >>>> Hi, >>>> >>>> you can use gr-ieee802-11 [1] to generate WiFi frames. Just start the TX >>>> flow graph and pipe the output to a file. >>>> I uploaded a frame (IQ data, no noise) [2] for you that you can use to get >>>> started. >>>> >>>> I don’t use Matlab, so i don’t know how to import the data, but you can >>>> display the IQ samples with >>>> >>>> od -fw8 frame.bin >>>> >>>> There is also a GNU Radio script [3] that might be helpful. >>>> >>>> Hope it helps, >>>> Bastian >>>> >>>> >>>> [1] https://github.com/bastibl/gr-ieee802-11 >>>> [2] https://www.ccs-labs.org/~bloessl/frame.bin >>>> [3] >>>> https://github.com/gnuradio/gnuradio/blob/master/gr-utils/octave/read_complex_binary.m >>>> >>>> >>>> >>>> On 02 Oct 2014, at 17:25, Ernest Szczepaniak <ernest_szczepan...@wp.pl> >>>> wrote: >>>> >>>>> Greetings engi's! >>>>> >>>>> I'm currently working on my masters (802.11 wlan receiver with >>>>> MATLAB/USRPN210). After creating all the important stuff ie: >>>>> >>>>> -symbol finder >>>>> -time synchronization >>>>> -coarse and fine frequency compensation >>>>> -symbol demodulator >>>>> -deinterleaver >>>>> -Viterbi decoder >>>>> -descrambler etc. >>>>> -MAC layer decoding >>>>> >>>>> i'm looking for any tested 802.11 a/g IQ signal for further research >>>>> becouse live samples captured by USRP seem to have incorrect result's >>>>> (wrong frame type MAC field, random MAC adress, CRC, parity bits etc). >>>>> >>>>> And here comes my 1st question. >>>>> >>>>> Is there any place where i can get some real, tested IQ wlan signal i >>>>> a/g standard and full description (rate, coded data, adresses, included >>>>> MAC fields)? Tried with Agilent Signal Studio but files are saved in >>>>> .wfm encrypted format :( >>>>> >>>>> I also found GRC beacon frames transmitter, written in GRC >>>>> >>>>> http://rrsg.ee.uct.ac.za/members/jwamicha/gr-wlan.tar.gz >>>>> >>>>> but due to having GRC 3.7 (where 'gnuradio-core' was repleaced with >>>>> 'gnurdaio-runtime') i can't simply compile this file becouse of an >>>>> error: >>>>> >>>>> --------------------------------------------------------------------------- >>>>> >>>>> checking for GNURADIO_CORE... configure: error: Package requirements >>>>> (gnuradio-core >= 3) were not met: >>>>> >>>>> No package 'gnuradio-core' found >>>>> >>>>> Consider adjusting the PKG_CONFIG_PATH environment variable if you >>>>> installed software in a non-standard prefix. >>>>> >>>>> Alternatively, you may set the environment variables >>>>> GNURADIO_CORE_CFLAGS >>>>> and GNURADIO_CORE_LIBS to avoid the need to call pkg-config. >>>>> >>>>> --------------------------------------------------------------------------- >>>>> It seems that those binaries arent compatible with my GRC version :( >>>>> >>>>> Any helpful guy to install this library and send me IQ signal of this >>>>> beacon frame? (in any MATLAB readable format - simple file sink in GRC). >>>>> >>>>> Looking forward for any reply. >>>>> >>>>> Thanks >>>>> >>>>> >>>>> _______________________________________________ >>>>> Discuss-gnuradio mailing list >>>>> Discuss-gnuradio@gnu.org >>>>> https://lists.gnu.org/mailman/listinfo/discuss-gnuradio >>>>> >>>> -- >>>> Dipl.-Inform. Bastian Bloessl >>>> Distributed Embedded Systems Group >>>> University of Paderborn, Germany >>>> http://www.ccs-labs.org/~bloessl/ >>>> >> _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org https://lists.gnu.org/mailman/listinfo/discuss-gnuradio
