(14)
Under the constraints set by the video codec and the mesh wireless network
infrastructure, the optimization of (12) attempts to find the cross-layer parameters that
maximize a capacity-distortion utility function. This function is formulated as the product
of the minimum path capacity (expressed by the remaining reserved time within the current
service interval at the most congested link) and the expected source distortion-reduction of
(13). In this way, we minimize congestion across the various links (since the path whose
worst link is having the highest capacity is selected under Dv,expected given by (13)), and
concurrently maximize the expected distortion reduction (under the current path??™s
minimum link capacity { } total ,
1
min ( )
i
i j
j
c l
?? ?‰¤ <
). The granularity of this optimization is one
MSDU. However, coarser granularities could also be considered, in order to reduce
complexity. The problem constraints can be expressed for each MSDU v as:
( ) max deadline , and : , i i i v v v dL d ??? ??? ??? ?¤ ?‰¤ p p p P (15)
i.e., the maximum transmission delay through each possible path must be below or equal to
the MSDU deadline ( deadline
v d ) in order for the video data to be useful to the decoder.
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