Re: [Discuss-gnuradio] choosing start of frame bits, studies?

2008-01-11 Thread Johnathan Corgan
Dan Halperin wrote: > Standards for access codes are interesting. The Barker spreading code > use in 802.11 1 and 2Mbps rates, for instance, is one of a set of > optimal codes where B (dot) B = |B| while > B (dot) (B rotated by any nonzero number of bits) = 1. This means that > if you're sliding a

Re: [Discuss-gnuradio] choosing start of frame bits, studies?

2008-01-11 Thread Dan Halperin
-BEGIN PGP SIGNED MESSAGE- Hash: SHA1 George Nychis wrote: > Was the access code picked randomly, or was there some basic rule of > thumb for generating it? What about the threshold of 12? What about > choosing a 64bit access as opposed to 32bit? Standards for access codes are interesti

[Discuss-gnuradio] choosing start of frame bits, studies?

2008-01-11 Thread George Nychis
Hi all, The gr_correlate_access_code_bb block takes a 64-bit access code as input to detect the start of incoming frames using a hamming distance with a threshold. The packet utilities has a default access code and uses a threshold of 12. I'm not sure who wrote the code and who picked the d