Ultra Wide Band

An Ultra-Wide-Band networks can form a mesh network, in addition, the main feature is the RTLS: Real-Time-Locating-System capability.

RTLS Gen 2 #

  • DW3000 IC family IEEE 802.15.4z, IEEE802.15.4-2015 UWB,…
  • using nRF52833 as host capable of Thread and Bluetooth Mesh and Direction finding

RTLS Gen 1 #

  • DRTLS : DWM1001 Two-Way-Ranging RTLS
  • RTLS : Real Time Locating System
  • PANS : Positioning and Netowrking Stack
  • eCos : Free Open source Real-Time Operating-System

Decawave provides a ready to use localisation system based on a preflashed DWM1001_PANS_R2.0.hex firmware. The functional concept is described in DWM1001 System Overview and Performance.pdf including the time division protocol and the format of all the 802.15.4 Frames.

Hardware #

UWM Chips available from Decawave, now Qorvo. Qorvo is also the supplier of Apple UWB chips.

More details about the UWB DWM1001 development kit :

Module Firmware #

  • Production Firmware : available as precompiled binary DWM1001_PANS_R2.0.hex in order to recover the Module for production grade certified applications
  • PANS library : All the main functions performed by the module (TWR, RTLS, Bluetooth, 802.15.4) are provided as a library on top of which a user nRF52832 application can be built.
  • PANS library API : described in DWM1001-Firmware-User-Guide.pdf and DWM1001-API-Guide.pdf
  • Open Source Firmware : multiple examples are provided to kick start development

out of the box config

system information log
 DWM1001 TWR Real Time Location System

 Copyright :  2016-2019 LEAPS and Decawave
 License   :  Please visit https://decawave.com/dwm1001_license
 Compiled  :  Jun  7 2019 18:00:03

 Help      :  ? or help

dwm> si
[000042.580 INF] sys: fw2 fw_ver=x01030001 cfg_ver=x00010700
[000042.580 INF] uwb0: panid=x0000 addr=xDECA50BFBF5001D2
[000042.590 INF] mode: tn (pasv,twr,np,le)
[000042.590 INF] uwbmac: disconnected
[000042.590 INF] uwbmac: bh disconnected
[000042.600 INF] cfg: sync=0 fwup=0 ble=1 leds=1 le=1 lp=0 stat_det=1 (sens=1) m                                   ode=0 upd_rate_norm=1 upd_rate_stat=100 label=DW01D2
[000042.610 INF] enc: off
[000042.610 INF] ble: addr=E0:69:AF:07:D2:94

  • DWM1001_PANS_R2.0.hex has the same firmware version but compiled on a different date Compiled : Mar 27 2019 03:35:59

Firmware recovery

nrfjprog -f nrf52 --program DWM1001_PANS_R2.0.hex --sectorerase --verify

Product Page #

PANS binary library for nRF52832 module DWM1001

  • Path v9_dwm_on_board_package/examples : dwm-api-test, dwm-range-iot, dwm-simple, dwm-sniffer, dwm-timer, dwm-uart
  • API 2.2, Firmware 1.3.0 : DWM1001 PANS Library Version 1.3.0
  • Transciever API not exposed, used by the library as dwm_ functions provided as binary files dwm.o, libdwm.a,…
  • available .emProject project files for Segger Studio
  • based on Nordik SDK version 12.1.0
  • Used GNU Tools ARM Embedded version 5.4 2016q3
Although reporting the same firmware version, two UWB commands are missing from the PANS lib utpg, utps (transmit power get and set)

Decawave Github #

Transciever driver DW1000 for nRF52

  • Path dwm1001-examples/examples/ : ss_twr_init, ss_twr_init_int, ss_twr_resp, twi_accel
  • DWM1001 board definition (leds, buttons,…)
  • based on Nordik SDK version 14.2.0
  • decadriver : DW1000 Device Driver Version 04.00.06
with Embedded studio V5.40, it is required to enable the updated #ifdef for __putchar in retarget.c line 100

Github mynewt #

Core source code for MAC layers and ranging

using the core functions and adding TDMA, Clock calib,…

  • examples : sniffer, OTA, TWR, TDOA,…
  • running over Apache’s myNewt Operating System which comes with code for BT, network,…

Zephyr Official #

  • module port as decawave_dwm1001_dev board with .dts
  • transciever driver decawave,dw1000 integrated in the spi dts entry
  • no uwb specific positioning code

Zephyr Community #

Community contribution of Zephyr based examples with decadriver

  • using custom board nrf52_dwm1001
  • Path dwm1001/examples
  • ex_01 … ex_14 (simple, sleep, sniff, twr, low power, accell,…)
  • decadriver DW1000 Device Driver Version 05.01.00
  • logs through RTT and serila
    GNU GLP v3
    using Zephyr 2.5 config Patches for double floats print %lf and CONFIG_NEWLIB_LIBC=y CONFIG_NEWLIB_LIBC_FLOAT_PRINTF=y, also sprintf string overflow needs size increase

Arduino #

  • No longer maintained
  • not supporting all functions, e.g. antenna calibration
  • License : Apache 2.0
  • TWR
  • Fork of arduino-dw1000
  • License : MIT
  • TWR

DW Tranceiver #

available in a Decawave webpage

  • User Manual : latest version 2.18 as of May 2021
  • Transmission, Reception, MAC features, Calibration,…

application note and datasheet from forum post (note the datasheet on the product page is version 1.8)

SDK available from Decawave uploads as zip

  • document User Guide : dw1000_api_rev2p14\dw1000_api_rev2p14_stsw\DW1000_Software_API_Guide_rev2p7.pdf
  • source code decadriver : DW1000 Device Driver Version 05.01.00
  • ported to STM32 platforms coocox and stsw

Raspberry pi software #

  • DWM Daemon
  • DWM Proxy
  • webapp http server
  • dwm device on /dev/dwm0

check that your raspberry pi is a model 3b not b+ with 100 Mbit only with sudo ethtool eth0 | grep Speed, which is important for the real time operation of the services.

DWM Daemon #

  • service : dwm1001.service
  • log : /var/log/dwm-daemon.log
  • config : /etc/dwm1001/dwm1001.config

DWM Proxy #

  • service : dwm1001-proxy.service
  • config : /etc/dwm1001/dwm1001-proxy.config

Decawave Webapp #

  • the webapp is provided on the raspberry pi on the path /var/www/html/.
  • The webapp is based on three.js which is a viable choice for 3d gemoetry calculations of anchors and tag coordinates.
  • The view is limited to an orthogonal projection which makes the app 2d only. Although the created tags and anchros are actual 3d meshes, only 2d shapes appear on the screen.
  • The down side of 3d is the need for ray casting to create click events on objects. But on the upside it’s a frameowrk that can easily extend to 3D models. Maybe for the future, Decawave will get inspired by the smart home 3d webapp project.
  • The menus are handled with injected jquery html with classes.
  • All in all, this webapp is an amazing user experience and a reference for open design, that’s how all mdoern apps should be

An easy upload function allows to customize the view with an own floor map. The offset and scale is not easy but manageable

MQTT Config #

The decawave webapp communicates with all devices through the 802.15.4-uwb mesh network to send and receive configuration. For that purpose, the IOT Data message is used as config request and response packets.

  • Details of the IoT Data message are provided in DWM1001_System_Overview.pdf section 9.1.12 IOT Data message
  • config can be updated by sending a request
    • topic dwm/node/<nodeid>/downlink/config
    • 802.15.4-uwb downlink message id UWBMAC_FRM_TYPE_DL_IOT_DATA
  • config is received by a response
    • topic dwm/node/<nodeid>/uplink/config
    • 802.15.4-uwb uplink message id UWBMAC_FRM_TYPE_UL_IOT_DATA

given that the response is a confirmation it will have a payload similar as the request

example Anchor config downlink
  "configuration": {
    "label": "RearRight",
    "nodeType": "ANCHOR",
    "uwbFirmwareUpdate": false,
    "leds": false,
    "ble": false,
    "anchor": {
      "routingConfig": "ROUTING_CFG_OFF",
      "initiator": false,
      "position": {
        "x": 3.5500002,
        "y": 1.1,
        "z": 0,
        "quality": 100
example Tag config downling
  "configuration": {
    "label": "BatteryTag",
    "nodeType": "TAG",
    "uwbFirmwareUpdate": false,
    "leds": false,
    "ble": false,
    "tag": {
      "locationEngine": true,
      "responsive": true,
      "stationaryDetection": true,
      "nomUpdateRate": 100,
      "statUpdateRate": 2000

Standard #

References #


What is Ultra Wide Band ?
It’s a radio technology that is not based on classical frequency or amplitude modulation rather uses a rich signal pulses that occupies a large spectrum band.
What does Ultra Wide Band mean for home automation ?
Very low energy level allows small battery operated tags to achieve functions like precise indoors positioning, which so far could only be achieved with heavier equipment like cameras that need high processing power localisation algorithms.