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Hi arnaud, thanks for your reply, So the matrix multiplication from CMSIS library is known to have some specific values that do not work? I'm using a custom firmware to understand and maybe test sightly changes of the TDoA2 localization algorithm, can you explain (or point me where to look at) how y...

Hi, I've noticed that sometimes the EKF reaches high variance in stateEstimatorScalarUpdate() and that leads to a filter reset. This is due to mat_mult() (from CMSIS-DSP library ) returning inf or nan values sometimes. Have you experienced the same thing? How can I reduce this to achieve better posi...

Can someone explain the kalman filtering applied to TDOA measurements? In particular the function stateEstimatorUpdateWithTDOA() What's the meaning of these lines? h[STATE_X] = ((x - x1) / d1 - (x - x0) / d0); h[STATE_Y] = ((y - y1) / d1 - (y - y0) / d0); h[STATE_Z] = ((z - z1) / d1 - (z - z0) / d0)...

Are you using the stock firmware in the anchors? Yes, I'm using the last commit, I've only added a serial submenu for power settings (I'll make a pull request soon with that) If so can you tell me the commit/version you are using and the configuration of each anchor so that I can try to reproduce t...

Hi Arnaud, thank you for your reply! are the anchor close to a very radio-reflective material like metal or concrete and is the line of sight clear of obstacle? The anchors are at 20cm from concrete, the line of sight is clear. it looks like multipath to me I suppose it is not, I swapped anchor 1 (c...

Hi, first of all thank you for all this amazing work with Loco Positioning! I'm debugging a TDOA setup with 8 nodes, here's the 3 raw TDOA readings using the first 4 nodes: https://preview.ibb.co/mv1Jgn/tdoa_debug.png Here's roughly the 0-3 nodes placement and in green the 5 positions where I moved ...

Very interesting, I'm also trying to get better results from TDOA, what are the TDMA_SLOT_BITS?