[SLS-CC] [Sls-slp] Making LDPC coding a work item in the C&S WG

[Marjorie de Lande Long]

Greg,

I have a question about the revised (2_24_2010) White Paper for Prox-1
LDPC.   The timing services would depend on knowing the path delays,
including delays caused by the LDPC encoding and decoding.  The time
measurement at the sending end is made when the last bit of the normal
Prox-1 ASM is output to the bitsteam.  The bitstream is input to LDPC
processing, where it is divided into 1024-octet blocks.  There seems to
be no predictable relationship between the Prox-1 PLTUs and the LDPC
blocks, so a Prox-1 ASM could end on any bit within a 1024-octet block.

Does the path delay for the arrival of the Prox-1 ASM depend on how it
happens to fall relative to the LDPC 1024-octet blocks?  For example,
would the delay for an ASM that ends near the end of a block be the same
as for an ASM that falls across a block boundary?

Best regards,
Marjorie

Marjorie de Lande Long
I B + M A de Lande Long
Software + Consultancy
marjorie at delandelong.com