Sync Word Generation Questions
Original Post: baseband : sync word (eGroups Msg. ) Date: 2001-01-03
Many doubts arise with the generation of the sync word used in the
Access code, here are some commonly asked questions & answers:
Mod Type
In page 145 of bluetooth spec section 13.2.1 the formula c(d) =
D34[x(d)] mod g(d) is used to calculate the parity bits of the (64,30) expurgated block
code . this is whether it's mod-2 division ( similar to one used with crc
calculations).Not any other division.
Generator Polynomial
The generator polynomial used to generate the code word is given by:
260534236651(octal notation).
+ sign meaning
The ( + ) sign indicates the 'xor' operation between the data and
the pnsequence, not an 'or' operation.
Pseudo Random Noise
The pseudo random noise seq p(d) used is a constant pn
sequence:3 F2 A33 DD69 B121 C1(hex).
with p0 as the left most bit.
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