BU03-Kit Development Board (Hardware Section 1)

——AndyL

1. Hardware Overview

1.1 About BU03-Kit

The BU03-Kit is a UWB development board based on the BU03 (DW3000) module and powered by an STM32F103C8T6 MCU. The BU03 module integrates an onboard antenna, RF circuitry, and power management.

It supports Two-Way Ranging (TWR) and Time Difference of Arrival (TDOA) positioning with up to 10 cm accuracy and a maximum data rate of 6.8 Mbps. Applications include IoT, mobile devices, wearables, and smart home solutions.

 

1.2 Key Features of BU03

 

Typical Power Consumption (@3.3V, 25°C):

Mode

Average Current (mA)

CH5 TX @ 0.85 Mbps

17.03

CH5 TX @ 6.8 Mbps

15.06

CH9 TX @ 0.85 Mbps

24.85

CH9 TX @ 6.8 Mbps

22.6

CH5 RX @ 0.85 Mbps

39.81

CH5 RX @ 6.8 Mbps

40.01

CH9 RX @ 0.85 Mbps

49.23

CH9 RX @ 6.8 Mbps

48.05

Instantaneous Startup Current

174 mA

Deep Sleep Current

179 nA

 

1.3 Pin Definitions

Pin

Name

Description

1

EXTON

External device enable during wake-up; used to minimize power consumption.

2

WAKEUP

Brings DW3000 from sleep/deep sleep to active mode. Tie to GND if unused.

3

RSTN

Reset pin, active low; equivalent to power cycle reset.

4

IO7

GPIO7 / SYNC input; reconfigurable if SYNC not used.

5

VDD

Power input (1.8V–3.6V), ≥200mA recommended.

6-7

VCC

Power input (2.5V–3.6V), ≥200mA recommended.

8

GND

Ground.

9

IO6

GPIO6 / SPIPHA / EXTRXE; SPI phase select or external RX enable.

10

IO5

GPIO5 / SPIPOL / EXTTXE; SPI polarity select or external TX enable.

11

IO4

GPIO4 / EXTPA; external power amplifier enable.

12

IO3

GPIO3 / TXLED; drive LED after transmission.

13

IO2

GPIO2 / RXLED; drive LED during reception.

14

IO1

GPIO1 / SFDLED; LED indicator when SFD (start frame delimiter) is detected.

15

IO0

GPIO0 / RXOKLED; LED indicator for successful frame reception.

16

GND

Ground.

17

CSN

SPI chip select (SPICSn); also used for waking from sleep modes.

18

MOSI

SPI data input.

19

MISO

SPI data output.

20

CLK

SPI clock input.

21

NC

Not connected.

22

IRQ

GPIO8 / IRQ output; active high by default; reconfigurable.

23

NC

Not connected.

24

GND

Ground.

Note : All GPIOs except SPICSn have internal pull-down resistors. SPICSn has an internal pull-up for safe operation when un-driven. Resistance varies with VDD (10kΩ at 1.8V to 30kΩ).

2. About the BU03 Module

The BU03 is an ultra-wideband (UWB) module based on Decawave’s DW3000 chip.

2.1 What is UWB?

Ultra-Wideband (UWB) is a wireless technology that transmits data via very short pulses instead of traditional carriers. The shorter the pulse in the time domain, the wider its bandwidth in the frequency domain — often reaching GHz levels.

Key advantages of UWB:

UWB systems typically follow the IEEE 802.15.4z standard, using Impulse Radio techniques.

 

2.2 UWB Positioning Methods

Distance-based methods:

 

Angle-based methods:

 

2.3 Comparison with Other Positioning Technologies

Metric

UWB

BLE 5.1+

Wi-Fi RTT

RFID

GPS

Accuracy

Centimeter-level (±0.5–10cm)

Meter-level (1–5m)

Meter-level (1–3m)

Meter-level (1–10m)

5–10m (outdoor)

Interference Resistance

Excellent

Weak

Moderate

Weak

Weak indoors

Power Consumption

Low (higher than BLE)

Very Low

High

Low (esp. passive RFID)

High

Latency

Microseconds

Milliseconds

Milliseconds

Seconds

Seconds

Range

Short (<100m)

Medium (<100m)

Medium (<150m)

Short (<15m)

Global

Multipath Resistance

Excellent

Poor

Moderate

Poor

Poor

Typical Applications

Digital keys, AR/VR, industrial automation

Indoor navigation, asset tracking

Indoor location services

Warehouse management, access control

Outdoor navigation