DW3000 MakerFabs Library Configuration

Wireless Connectivity Ultra-Wideband
1

I am trying to work on a multiple anchor DS-TWR example, it works fine but the problem is that ranging really gets hit after 10ish meters, after that anchors give very high amount of peaks and connectivity starts stutter. I tried to solve this issue by changing the dwt_config but when i change it this happens:

-Tag sends its messsage
-Anchor receives the message
-Anchor sends its response
-Tag does not receive that response

Here is the configuration that worked:

   static dwt_config_t config = {
    5,                /* Channel number. */
    DWT_PLEN_128,     /* Preamble length. Used in TX only. */
    DWT_PAC8,         /* Preamble acquisition chunk size. Used in RX only. */
    9,                /* TX preamble code. Used in TX only. */
    9,                /* RX preamble code. Used in RX only. */
    1,                /* 0 to use standard 8 symbol SFD, 1 to use non-standard 8 symbol, 2 for non-standard 16 symbol SFD and 3 for 4z 8 symbol SDF type */
    DWT_BR_6M8,       /* Data rate. */
    DWT_PHRMODE_STD,  /* PHY header mode. */
    DWT_PHRRATE_STD,  /* PHY header rate. */
    (129 + 8 - 8),    /* SFD timeout (preamble length + 1 + SFD length - PAC size). Used in RX only. */
    DWT_STS_MODE_OFF, /* STS disabled */
    DWT_STS_LEN_64,   /* STS length see allowed values in Enum dwt_sts_lengths_e */
    DWT_PDOA_M0       /* PDOA mode off */
};

And here is the one I tried and did not work:

static dwt_config_t config = {
    5,            /* Channel number. */
    DWT_PLEN_4096, /* Preamble length. Used in TX only. */
    DWT_PAC32,     /* Preamble acquisition chunk size. Used in RX only. */
    9,            /* TX preamble code. Used in TX only. */
    9,            /* RX preamble code. Used in RX only. */
    1, /* 0 to use standard 8 symbol SFD, 1 to use non-standard 8 symbol, 2 for
          non-standard 16 symbol SFD and 3 for 4z 8 symbol SDF type */
    DWT_BR_850K,      /* Data rate. */
    DWT_PHRMODE_STD, /* PHY header mode. */
    DWT_PHRRATE_STD, /* PHY header rate. */
    (4096 + 1 + 64 - 32), /* SFD timeout (preamble length + 1 + SFD length - PAC size).
                      Used in RX only. */
    DWT_STS_MODE_OFF, /* STS disabled */
    DWT_STS_LEN_64,   /* STS length see allowed values in Enum dwt_sts_lengths_e
                       */
    DWT_PDOA_M0       /* PDOA mode off */
};

Any help would be appriciated.

2

Do you have any receive timeouts set? Dropping the data rate and increasing the preamble lengths will make your packet take significantly longer to transmit. If you have a timeout set and didn’t increase it then it could be that your receive is timing out and giving up before the packet has arrived.

3

Thanks for the reply,
I am trying it but it doesn’t solve the problem no matter how high i set it to, is there a way that I can calculate the value I need to assign.

4

The link here Power Calculator Released - #5 by AndyA can calculate the packet duration for a given set of settings.
It was for the DW1000 so no STS support but other than that the times should be valid.

5

That looks like a great tool, hope it works for me

6

It’s pulled from a decawave tool that they released a while back.
They had a java app that calculated power consumption and packet duration for the DW1000. The app broke years ago but all it was doing was acting as a front end for that excel file. For a while after that the excel file was still on their site if you knew the location (which was in the apps error message) so I grabbed a copy.

7

Thanks this worked but for only preamble length of 256 symbols, seems like I need to do more tests. For someone who will come to this thread here is the config I used that increased the range of stable communication :

dwt_config_t config = {
    5,            /* Channel number. */
    DWT_PLEN_256, /* Preamble length. Used in TX only. */
    DWT_PAC16,     /* Preamble acquisition chunk size. Used in RX only. */
    9,            /* TX preamble code. Used in TX only. */
    9,            /* RX preamble code. Used in RX only. */
    1, /* 0 to use standard 8 symbol SFD, 1 to use non-standard 8 symbol, 2
          for non-standard 16 symbol SFD and 3 for 4z 8 symbol SDF type */
    DWT_BR_6M8,       /* Data rate. */
    DWT_PHRMODE_STD,  /* PHY header mode. */
    DWT_PHRRATE_STD,  /* PHY header rate. */
    (257 + 8 - 16),    /* SFD timeout (preamble length + 1 + SFD length - PAC
                         size).    Used in RX only. */
    DWT_STS_MODE_OFF, /* STS disabled */
    DWT_STS_LEN_64,   /* STS length see allowed values in Enum
                       * dwt_sts_lengths_e
                       */
    DWT_PDOA_M0       /* PDOA mode off */
};

and you should set the RX_TIMEOUT_UUS to 6400000 which is used in the function dwt_setrxtimeout.

8

Hi @hsnbrky , did you manage to increase your range?
I am also stuck now at 10 meters.
If I change the set-up (Frequency and preamble), what should I change in the library?

9

hi @JT_1
image

Here is the dwt_config_t I used while reaching 40-50 meters. But for this to work you need to change some delay values :
image

Also you need to increase the TX power but this may exceed radio regulations:

dwt_txconfig_t txconfig_options =
{
    0x34,           /* PG delay. */
    0xffffffff,      /* TX power. */
    0x0             /*PG count*/
};

With this i got a pretty stable RTLS solution but i want to warn you, I don’t think you should use 3rd party boards instead you can use DWM3001CDK board which is more stable, easier to configure with the SDK and has more range, I could get 73 meters range with this board.

Edit: They are also cheaper