The fullrank value function

Motivated by applications to the wiretap channel of type II with the coset coding scheme as well as secret sharing, the concept of the fullrank value function is introduced in this paper. Several constructing methods for fullrank value functions are presented by using the finite projective geometry. The relationship between fullrank value functions and secret sharing schemes, and the relationship between fullrank value functions and separation of linear codes are given as well. In particular, new (2,2)-separating codes are constructed by using our methods.