Correction to ‘A note on the discrete Lyapunov and Riccati matrix equations’
M. T. TRAN, Mahmoud Edwin Sawan · International Journal of Control · 1987
In Tran and Sawan (1984), we derived a lower bound for the determinant of the discrete algebraic Riccati equation where A, B, P, Q are n x n matrices, Q = Q T > 0 and Rank (B) = n. We assumed that BB T>Q and the matrix A is stable. The purpose of this note is to include an additional assumption about the above equation in order for the result of Theorem 1 given in Tran and Sawan (1984) to be valid. Without the additional assumption, this theorem would be invalid as has been pointed out by Kwon and Youn (1985). The additional assumption is given below with the same notation as in Tran and Sawan (1984).