Re: stds-80220-requirements: Packet Error Rate requirement
On Wed, Jul 23, Joseph Cleveland writes ...
Joseph> 4.1.10 Packet Error Rate The physical layer shall be capable of
Joseph> adapting the modulation, coding, and power levels to accommodate RF
Joseph> signal deterioration between the BS and user terminals. The air
Joseph> interface shall use appropriate ARQ schemes to ensure that error
Joseph> rates are reduced to a suitably low level in order to accommodate
Joseph> higher level IP based protocols (for example, TCP over IP). If the
Joseph> received Eb/No exceeds the minimum required value for reliable
Joseph> reception as specified in Section 4.2.1, the packet error rate for
Joseph> IP packet for any active call shall be less that 1 percent after
Joseph> channel decoding for error correction and before ARQ with a 95%
Joseph> confidence.
<snip>
Joseph> An implied requirement is that if the link for the active call
Joseph> cannot maintain a packet error rate < 1%, the call "shall" be
Joseph> terminated.
Joseph,
Elsewhere in the requirements document, there are requirements for adaptive
modulation and coding, and for power control which are intrinsic to the air
interface. I would argue that the conditions under which the IP packet error
rate exceeds 1% and an operator's actions in that case -- for example, to
terminate a data session -- are deployment issues that more properly belong
in the evaluation document.
Also, it seems likely that at least some of the air interface proposals
will fragment IP packets into air interface PDUs prior to transmission and
perform ARQ on the PDUs rather than on IP packets. For such systems, it's
hard to interpret "IP packet error rates before (air interface) ARQ." For
that reason, evaluation scenarios should specify "corrected" IP packet
error rates, where "corrected" means post-air-interface-ARQ in scenarios
where air interface ARQ is in effect.
Marc