... has been made and incorporated into target position estimation) for steady-state Singer g–h–k Kalman filter (After Fitzgerald, R J., ‘‘Simple Tracking Filters: Steady-State Filtering and Smoothing ... Simplified Kalman filter Kalman filter Surface or Subsurface Air 0 0 Note: ¼ within 20% of Kalman filter; ¼ 20–40% worse than Kalman filter; ¼ 40–70% worse than Kalman filter; ¼ more than 70% worse than Kalman ... by (2.4-12) g,h, and k are related by (1.310a) to (1.3-10c) [11, 14, 15] and , , and T are related to g and k by [14] a x T 4 k2 a ¼ 4 1Àg x ð2:4-14Þ For the general g–h–k Kalman filter (2.4-5)...