Ai-Thinker BU04 DW3220 Dual-Antenna UWB Positioning Module

The Ai-Thinker BU04 is a high-precision ultra-wideband positioning module for embedded RTLS and ranging hardware. The product listing identifies this module as the DW3220 version, while the official BU04 specification describes the hardware platform as a Decawave DW3000-series UWB design integrated with an STM32F103 MCU.

BU04 supports dual antenna channels, IEEE 802.15.4-2015 UWB, IEEE 802.15.4z BPRF mode, channel 5 and channel 9 operation, 850kbps and 6.8Mbps data rates, and positioning accuracy up to 10cm according to the official specification. It also provides SPI, UART, I2C, SWD, and multiple 3.3V GPIO resources for hardware integration.

For related OpenELAB UWB products and accessories, compare the Ai-Thinker BU04 Two-Way Ranging Sensor Board, Ai-Thinker BU03 DW3000 UWB Module, Ai-Thinker BU03 UWB Kit, Ai-Thinker BU01 UWB Module, and AntennaHome 3-10.6GHz UWB Antenna.

Technical Specifications

Integration Notes & Hardware Guidance

• Power Supply – Use a stable 3.3V rail where possible and reserve at least 500mA peak current for reliable UWB operation.
• Ripple Control – Prefer LDO power. If DC-DC power is used, keep ripple within 30mV and reserve dynamic response capacitance.
• Antenna Placement – Place the module at the motherboard edge or hollow out the antenna area to reduce obstruction around the onboard antennas.
• Metal Clearance – Keep metal parts and high-frequency components away from the antenna area to protect UWB RF performance.
• External Antenna Option – If using IPEX antennas, confirm channel selection, antenna match, cable loss, and final enclosure performance before production.
• Interface Planning – Confirm SPI, UART, I2C, SWD, and GPIO assignments before final PCB routing.
• Programming Access – Reserve SWDIO and SWCLK test points so the integrated STM32F103 can be programmed or debugged during production.
• IO Protection – Add 10 ohm to 100 ohm series resistors where appropriate and reserve ESD protection near exposed terminals.
• Production Handling – Treat BU04 as an ESD-sensitive MSL level 3 module and follow moisture-control handling before reflow soldering.

Packing List

• 1 x Ai-Thinker BU04 UWB DW3220 High-Precision Wireless Positioning Module

FAQ

Q: What is BU04?
A: BU04 is an Ai-Thinker dual-antenna UWB positioning module with an integrated STM32F103 MCU and DW3000-series UWB platform described in the official specification.

Q: Why does the title mention DW3220?
A: The OpenELAB product listing identifies this module as DW3220. The official BU04 specification describes the platform as Decawave DW3000-series UWB with STM32F103 MCU.

Q: What positioning accuracy is listed?
A: The official BU04 specification lists positioning accuracy up to 10cm.

Q: Which UWB channels does it support?
A: The official specification lists channel 5 and channel 9, with center frequencies of 6489.6MHz and 7987.2MHz in the RF table.

Q: What data rates are supported?
A: The official feature list includes 850kbps and 6.8Mbps data rate support.

Q: Does BU04 include antennas?
A: Yes. The official specification lists onboard PCB antennas and compatibility with IPEX sockets for external antennas.

Q: What power supply should I design for?
A: Use a 2.5V to 3.6V supply range, 3.3V typical, and reserve at least 500mA supply current as recommended by the official specification.