A Lower Bound for Variable Rate Slepian-Wolf Coding

In this paper we analyze the redundancy of variable rate Slepian-Wolf coding. For any memoryless source-side information pair (X, Y) = {(X
_i
,Y
_i
)}Einfin
_i=1
with finite alphabet, the redundancy R
_n
(epsi
_n
) of variable rate Slepian-Wolf coding is defined as the minimum of the difference between the compression rate of any variable-rate Slepian-Wolf code resulting from coding XEn
₁
with decoding error probability epsi
_n
, and the conditional entropy H(X|Y). It is proved that under mild assumptions, for sufficiently large n, R
_n
(epsi
_n
) is lower bounded by dradiclog n/n, where d > 0 is a constant