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Title
Lattice Quantization with Side Information: Codes, Asymptotics, and Applications in Sensor Networks.

Author
S. D. Servetto.

Status
IEEE Transactions on Information Theory; 53(2):714-731, 2007.

Abstract
We consider the problem of rate/distortion with side information available only at the decoder. For the case of jointly-Gaussian source X and side information Y, and mean-squared error distortion, Wyner proved in 1976 that the rate/distortion function for this problem is identical to the conditional rate/distortion function R_{X|Y}, assuming the side information Y is available at the encoder. In this paper we construct a structured class of asymptotically optimal quantizers for this problem: under the assumption of high correlation between source X and side information Y, we show there exist quantizers within our class whose performance comes arbitrarily close to Wyner's bound. As an application illustrating the relevance of the high-correlation asymptotics, we also explore the use of these quantizers in the context of a problem of data compression for sensor networks, in a setup involving a large number of devices collecting highly correlated measurements within a confined area. An important feature of our formulation is that, although the per-node throughput of the network tends to zero as network size increases, so does the amount of information generated by each transmitter. This is a situation likely to be encountered often in practice, which allows us to cast under new---and more ``optimistic''---light some negative results on the transport capacity of large-scale wireless networks.

More:
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Similar sublattices of the hexagonal lattice in two dimensions.

Related conference papers:

S. D. Servetto. Lattice Quantization with Side Information. In the Proceedings of the IEEE Data Compression Conference (DCC), Snowbird, UT, March 2000.

S. D. Servetto. On the Feasibility of Large-Scale Wireless Sensor Networks. In the Proceedings of the 40th Annual Allerton Conference on Communication, Control, and Computing, Urbana, IL, October 2002.