Re: [STDS-802-16] Clarification on OFDMA TDD frame duration
Both methods are appropriate, but for different
situations. Method two would be the normal case where we have a detected,
but uncorrectable bit error at the PHY level. This will catch almost all
errors and is not too difficult to implement in the MAC/PHY interface HW.
Method one is for the rare case where there was a bit error in the MAC error
that was both undetected and uncorrected by the FEC at the PHY
level.
Ken
Here is a question I received. Does
anyone have a good answer?
Avi
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We are working on hardware implementation of the
MAC802.16. As a member of this group, I am working on the TC (Transmission
Convergence) Sublayer and MAC interface of MAC802.16. During reception of
information from Physical layer, Physical layer reports the number of
irrecoverable
Bytes of each FEC code word; I wish to know which of the
following methods is suitable for implementation.
1. We can
verify HCS of each header and extract the length field, then buffer the data
according that length. If the HCS was wrong, in next FEC Code word, we check the
TC pointer to find out the PDU location and decide based on
it.
2. If the physical layer reports an irrecoverable, we have to
discard the packet and the job is running till we receive a packet without an
irrecoverable. Then we use this packet to find the start of the header using TC
pointer and if the next packet was erroneous, we discard part of the PDU we
saved before.
Best Regards,
Fahimeh
Nouri