andreabelles / Time-Synch

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Question about the use of xOld variable #9

Closed andreabelles closed 3 years ago

andreabelles commented 3 years ago

Problem with the following lines:

  1. https://github.com/andreabelles/Time-Synch/blob/5665f74d516edde918f0340ec4f1fdc3c304c40a/Estimation_Methods/skogEKF.m#L25
  2. https://github.com/andreabelles/Time-Synch/blob/5665f74d516edde918f0340ec4f1fdc3c304c40a/Estimation_Methods/skogEKF.m#L79

Problem using xOld(4). This variable in line 25 is supposed to be the delay we had at k-1. As it is the last estimation we had of the delay, it is the only value we can use to move from k (or k-1? Not sure if tspan should be at k or k-1) to k-Td. However, when we want to propagate from k-Td to k-1 (line 79) we are also using the same variable, as we haven’t obtained yet the delay at the current instant of time. Should we use the previous estimate of the delay (supposed to be at k-1) to correct the position at k-1 or use this delay to predict the delay at k?