Broadband Systems Laboratory Advisor : Prof. Chin-Liang Wang Presented by Yih-Shyh Chiou

1. 後 卓 越 計 畫 進 度 報 告 Broadband Systems Laboratory Advisor : Prof. Chin-Liang  Wang Presented by Yih-Shyh Chiou September 4, 2006

2. R1 R2 R Why Tracking and Prediction Are Needed in an Indoor Location Estimator (1/2) • Assume that at time t=t1 two people are detected at ranges R1 and R2; on the next sample at time t=t1+T, again two people are detected • The question arises as to whether these two people detected on the second sample are the same two people or two new people

3. #1 #2 The distance further away #1 #2 The prediction window Why Tracking and Prediction Are Needed in an Indoor Location Estimator (2/2) • On the nth sample, the people predicted and measured position, and , respectively R=R1 R=R2 sampling time = T

4. g-h Filter • The present velocity and position g-h track update (filtering) equations: • The g-h transition equations or prediction equations: • The prediction update equations of the g-h filter

5. Prediction step Updating step Filter aand bare tuning constants between 0 and 1 a=b=0: Measurement has no effect a=b=1: History has no effect

6. Properties • Properties of the g-h tracking filter • Steady-state performance for constant-velocity target • Steady-state response for target with constant acceleration • Tracking errors due to random range measurement error • To obtain the filter, we can take g-h filter and replace g with and h with • The tracker is a low-pass filter used to smooth out the effects of measurement noise