Abstract
In this paper, we consider the lossless quantum data compression scheme proposed by Bostr¨om and Felbinger. When no partial information is available about the dimension of the source space and the eigenvalues of the density operator associated with the quantum source, we obtain a new lower bound on the average base length of their proposed compression scheme in terms of the von Neumann entropy. We next consider the case that only the largest eigenvalue of the density operator is available as side information, and obtain a new lower bound on the average base length. Furthermore, given that the dimension of the source space and some eigenvalues of the density operator are available, we obtain a new lower bound on the average base length in terms of the von Neumann entropy and the available side information