Constructing network codes using Möbius transformations
نویسندگان
چکیده
We study error correcting constant dimension subspace codes for network coding. The codewords are F2-subspaces of F2n , having at most 1-dimensional intersections. F2n is contained in the automorphism group of the code. We give a lower bound for the size of such codes, being constructed by a greedy method. Further we describe a code in F22m with 23m codewords, for which we finally present a construction, an encoding and a decoding algorithm. This is based on the geometry of F22m as a 2-dimensional F2m space and the operation of fractional linear transformations.
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