Technical question for DWM1001-DEV

Wireless Connectivity Ultra-Wideband
1

Dear Qorvo Team,

Thank you for your support.

I have a technical question for DWM1001-DEV

At End User’s;
If the distance between the devices is more than 1.5m(Indoor positioning use), distance measurement is not possible,
which I don’t think should be the case given the purpose of the device.

He purchased 2 of these But same way.

He found that location detection was stable as long as the distance between anchors was within about 1.5 meters. However, this seems to contradict the product specifications. Previously, someone in a forum post asked about a configuration with a distance of about 10 meters.

Although it is not specified in the documentation, our goal is to operate with a density of approximately one anchor per 10 square meters. Specifically, we would like to use approximately eight anchors, eight tags, and three listeners to effectively monitor the flow of people in an area of ​​100 square meters or less.

Can you give some advice?

Kind Regards,
Takashi
T4817631

2

Dear Takashi,

The issues with performance are usually due to a wrong configuration of the dw1000 chip, or wrongly chosen components or bad antenna matching.

Because you are using dwm1001, the components and antenna are correct.

So, the only question is the FW which client is using. I would recommend go with stock FW examples for dw1000, and try to see if they demonstrate expected distance results.

Also, in general, for DW10000 you shall use PLEN 128 or longer, because for PLEN 64 chip requires special tuning.

FYI, the DW1000 chip/module with PLEN 128 on ch2 could do 70m in LOS, I personally did a project several years ago on such a distance with no problems.

1 Like
3

@alliv -san,

Thank you for your support.

End user said below,
I have read your reply.
I am relieved to hear that there are no problems with the DWM1001-DEV components and antennas.

I understand that the performance issues are most likely caused by the firmware.

In order to resolve the issue, I have checked all of the following official documents so far.

  • Product Brief
  • Product Data Sheet
  • Quick Start Guide
  • Maximizing Range in DW1000-Based Systems (Application Note APS017)
  • Channel Effects on Communications Range and Time Stamp Accuracy (Application Note APS006 Part 1)
  • Transmit Power Calibration and Management (Application Note APS023 Part 1)
  • MDEK1001 User Manual

In particular, as far as I can tell from the graph in Figure 6 of “Channel Effects on Communications Range and Time Stamp Accuracy (Application Note APS006 Part 1)”, it appears that communication of at least 10m is possible without any problems with appropriate settings.

However, the current situation is as we discussed.

Therefore, we have listed below the results of checking the firmware version currently in use.

dwm>si
[000056.990 INF] sys: fw2 fw_ver=x01030001 cfg_ver=x00010700
[000056.990 INF] uwb0: panid=xC524 addr=xDECAB12484C14FB0
[000057.000 INF] mode: ani (act,real)
[000057.000 INF] uwbmac: connected
[000057.010 INF] uwbmac: bh disconnected
[000057.010 INF] cfg: sync=0 fwup=0 ble=1 leds=1 init=1 upd_rate_stat=120 label=DW4FB0
[000057.020 INF] enc: off
[000057.030 INF] ble: addr=DB:8F:42:CA:C9:9E

Also, regarding PLEN (Preamble Length), I understand the logic that increasing the PLEN increases the communication distance.

However, I am struggling because I cannot find a way to check the current value of PLEN in the standard firmware.

In this regard, I have two questions.

  1. The manufacturer advised me that “PLEN 128 or higher must be used for the DW1000,” but is it correct to understand that PLEN is set to 128 by default in the standard firmware of DWM1001-DEV?

  2. If not, or to confirm, is there a way to check the current PLEN value through the UART shell of the standard firmware, etc.?

I would appreciate it if you could confirm the above.

In addition, regarding the “DWM1001-DEV standard firmware sample” proposed by the manufacturer, am I correct in understanding that this is the factory firmware (which has a UART shell as described above) that I am currently using?
If not, I would appreciate it if you could tell me how to obtain the corresponding sample firmware.

Can you give some advice?

Thank you so much for your patience.
Kind Regards,

Takashi

4

Hello @TakashiTheYakamein -san
let me help you here.

re firmware) The DWM1001C modules are provided without firmware. It is up to the user to create their own firmware. However Qorvo with LEAPS company has released a PANS firmware which can be used with the DWM1001C modules out of the box. This PANS firmware is closed source and it is not possible to change the RF parameters as it might violate the CE/FCC regulations. This firmware was developed to comply with these regulations.

re distance) With DWM1001C and PANS firmware you should be able to have the operating range around 20-30m - it depends on the environment. If you have just a few meters then there must be something wrong in your setup.

I have following questions:

  1. How do you power up the DWM1001C device. If you are using the RCR123A battery, then use some form Fenix or Keepower brand. Dont use GTL batteries (red ones), thy dont work well.
  2. Could you share the configuration of all your devices (si output)
  3. How are you devices mounted/placed - at the begging they should be placed on tripods, at least 1.5m above the ground.

Side note: As it looks like that you are from Japan then I have to inform you that the DWM1001C devices are not allowed to be used in Japan.

Cheers
JK