[Top][All Lists]

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: [Discuss-gnuradio] GRC 3.6 / 802.11 a/g test signal

From: Ernest Szczepaniak
Subject: Re: [Discuss-gnuradio] GRC 3.6 / 802.11 a/g test signal
Date: Mon, 6 Oct 2014 13:19:53 -0700 (MST)

Ok, so i decoded all of the payload (123 data symbols, de-interleaving every
one in receiver's loop). After Viterbi and descrambling it gives some
strange results:

7 of SERVICE bits are random - OK (i read in standard that those 7 bits are
0's at the transmitter, and will set receivers descrambler to correct
initial state).
9x0's in RESERVED field - OK.

and now:

FRAME CONTROL - !incorrect!

TAIL bit's looks fine (11x0's - 6 zeros from TAIL field and probably 5 PAD

I also checked autocorelation function of received data bits. It indicates
that there is some cyclicness in payload (every 96 bits function shows a
simple peak). Assuming that your frame consist of text:Hello world! - its 12
characters, 8 bits each - together 96 bits repeating sequence, but cant find
Hello world text.

Its rather imposible, that those results are correct.

You have mentioned that i should try with some test sequence (dont have any
one). If i will try to generate it on my own, i wouldnt be sure that its
following the standard :(


I was also searching for 48x"1" bit broadcast adress. Found only 43x"1" in
row. Close but not the same :D


View this message in context: 
Sent from the GnuRadio mailing list archive at Nabble.com.

reply via email to

[Prev in Thread] Current Thread [Next in Thread]