Achieving Lower Distortion with Lattice Strategies in Multicast Wireless Networks

The problem of network coding over a multiple-access channel (MAC) is considered in this paper. Lattice strategies of encoding indexes of messages are proposed, ensuring that if the sum of any two lattice points is another point over a finite field, then the sum of the two indexes mapped to these two points is equal to the index mapped to another point. In this way, the interference caused by other transmitters can effectively be canceled when the sum of the two indexes as a codeword of network coding is estimated. It is shown that the lattice strategies obtain more information for reconstructing sources than the existing methods in a modified version of the classical butterfly network.

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