Validation of the RTCA Message Format for WAAS Sep 1, 1995· Tsai , Y. J. , Enge , P. , Chao , Y. C. , Walter , T. Changdon Kee , Evans , J. , Barrows , A. , Powell , D. , Parkinson , B. W. · 0 min read Last updated on Sep 1, 1995 Authors Changdon Kee Professor ← An Algorithm for Inter-frequency Bias Calibration and Application to WAAS Ionosphere Modeling Sep 1, 1995 Comparison of Full Vector and Common View WAAS Algorithms Jun 1, 1995 →