1 research outputs found
Wireless Video Multicast with Cooperative and Incremental Transmission of Parity Packets
In this paper, a cooperative multicast scheme that uses Randomized
Distributed Space Time Codes (R-DSTC), along with packet level Forward Error
Correction (FEC), is studied. Instead of sending source packets and/or parity
packets through two hops using R-DSTC as proposed in our prior work, the new
scheme delivers both source packets and parity packets using only one hop.
After the source station (access point, AP) first sends all the source packets,
the AP as well as all nodes that have received all source packets together send
the parity packets using R-DSTC. As more parity packets are transmitted, more
nodes can recover all source packets and join the parity packet transmission.
The process continues until all nodes acknowledge the receipt of enough packets
for recovering the source packets. For each given node distribution, the
optimum transmission rates for source and parity packets are determined such
that the video rate that can be sustained at all nodes is maximized. This new
scheme can support significantly higher video rates, and correspondingly higher
PSNR of decoded video, than the prior approaches. Three suboptimal approaches,
which do not require full information about user distribution or the feedback,
and hence are more feasible in practice are also presented. The proposed
suboptimal scheme with only the node count information and without feedback
still outperforms our prior approach that assumes full channel information and
no feedback.Comment: 11 pages in double-column IEEE journal style. Submitted to IEEE
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