Heterotic matrix theory with Wilson lines on the lightlike circle

We develop a matrix model for the SO(32) heterotic string with certain Wilson lines on the lightlike circle. This is done by using appropriate T-dualities. The method works for an infinite number of Wilson lines, but not for all. The matrix model is the theory on the D-string of type I wrapped on a circle with a SO(32) Wilson line on the circle. The radius of the circle depends on the Wilson line. This is a 1 + 1-dimensional O(N) theory on a circle. N depends not only on the momentum around the lightlike circle but also on the winding and SO(32) quantum numbers of the state. Perspectives for obtaining a matrix model for all Wilson lines are discussed