[STDS-802-16] Query regarding RS encoding in 802.16a
> Hi all,
> Here i have a query regarding RS encoding procedure in 802.16a-2003. In
> 802.16a standard document one
> "Example OFDM UL RS-CC encoding" was given under 8.4.3.5. In that, the
> randomized data was given as
> D5 0E A4 AA EF E4 DB 51 88 91 6B 00 DF AA 1E E7 02 A8 0E 70 4F 7F C9 D8 66
> 1D 9D F0 E7 20 E4 9D 7A 32 91
> and the Reed-solomon encoded data as
> 95 CE 22 76 D5 0E A4 AA EF E4 DB 51 88 91 6B 00 DF AA 1E E7 02 A8 0E 70 4F
> 7F C9 D8 66 1D 9D F0 E7 20 E4 9D 7A 32 91 00
> where 95 CE 22 76 are the parity bits that we get after encoding the
> randomized data. That means the parity bits were sent first and then the
> actual data part. That means one should have a buffer for the data part so
> that we send the parity bits first and then data part.
>
> But in the same standard, for OFDMA case there is another example. In
> 8.5.9.4.4, "Example of OFDMA UL RS-CC encoding" the randomized data
> was given as
> 5B 23 80 44 35 82 06 07 47 67 CB 37 1F 1A 9D 44 0B 62 3A CC F4 F4 50 E1 30
> 8A 6A 80 D4 00 4E 5E 84 BA 96 57
> and RS encoded data as
> 5B 23 80 44 35 82 06 07 47 67 CB 37 1F 1A 9D 44 0B 62 3A CC F4 F4 50 E1 30
> 8A 6A 80 D4 00 4E 5E 84 BA 96 57 3A CE 4E 81 36 AB DA 26 13 3E D1 3B
> That means the parity bits 3A CE 4E 81 36 AB DA 26 13 3E D1 3B were added
> after the data part. In this case, we may not need storage to buffer the
> data part.
> Can some one tell me why there is a difference like that?
> Which one is correct? I will be greatful if some one throgh some light on
> this.
>
> Thanks and Regards,
> Sridhar Nandula
> Sr Design Engineer
> Isofttech Pvt Ltd,
> Chennai, +91-44-24364915 ext 54
> India