Re-ordering/Interleaving [Under GSM > Full rate speech coding illustration]
The 456 bits are re-ordered and partitioned in 8 bursts - even bits of first 4 bursts and odd bits of next 4 bursts - 57 bits in a burst (Ref 45.003:3.1.3).Above bits are encrypted (using CK) and then actual bursts are formed. Normal burst have following format (Ref 45.002:5.2.3):
| Tail bits(3) | Info bits(57) | Steal bit | Training sequence(26) | Steal bit | Info bits(57) | Tail bits(3) |
Below are actual normal burst data (Ref 45.002:5.2.3,45.003:3.1.3/4):
References: GSM book by Mouly and Pautet.
© Copyright Samir Amberkar 2013
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