UWB Base Station Module

1. Introduction
Before that, we need to do a project. In the project, we need to complete the indoor positioning requirement. For indoor positioning, UWB ultra-wideband technology has been a popular technology in recent years. With it, centimeter-level positioning can be achieved. However, the price of UWB modules is still high. It may be because most of the UWB modules are currently produced by Decawave (currently acquired by Qorvo), which leads to a shortage of supply. I hope that domestic companies can successfully develop such chips and bring down the price.
 
2. Introduction
 
 
Then let me talk about the design of this board. The main control chip is GigaDevice's GD32F310F4P6TR, which is a less common MCU using the Cortext-M4 architecture. When designing, I thought about which chip to buy at a low price, and I immediately fell in love with this one. After completing the design, I found that this chip is simply perfect. First of all, the MCU has only 20PINs. In this board, I just used up all the IO interfaces, including the SPI function pins, debug serial ports, SWD debug pins, etc. for the UWB module. Secondly, the MCU is based on the Cortext-M4 architecture. Because indoor positioning requires a lot of floating-point calculations, the MCU comes with a floating-point unit to speed up the calculation efficiency. The
UWB module uses the BU01 module of Anxinke, which is designed based on DMW1000 and supports 5 UWB frequency bands; but because UWB is still an emerging technology, there is little related code information, and it is still quite difficult to write a project.
Because when designing, it is considered that the base station module is usually placed far away from the host, so it is obviously not appropriate to use a USB interface for power supply, so the board only supports battery power supply. The shape of the entire board is designed according to the shape of the 18650 battery, leaving a screw hole for fixing the battery compartment, and the battery compartment will be centered with the board after installation.
Because it only supports battery power supply, I specially designed a circuit for battery power detection, which is a simple series voltage divider circuit plus a filter capacitor. Because the voltage range of general lithium batteries is between 3.7-4.2V, but the ADC of the microcontroller generally only supports the detection of 3.3V voltage (related to the hardware design), so a series voltage divider circuit is used to cut the battery voltage in half for detection; the two capacitors responsible for voltage division only need to have the same resistance value. I used a 49.9kΩ resistor. If not, you can replace it with 10kΩ, 100kΩ, 47kΩ, etc.
 
3. Functions
The board has the following functions:
Equipped with the Anxinke BU01 module, it can realize the UWB ultra-wideband signal transmission
and reception Lead out debug serial port interface
Lead out SWD download debug interface
Battery power supply
Support battery power detection
 
Note: The SWD download debug interface is designed according to the Wildfire downloader. If you use other downloaders, be sure to check the pins
 
4. Physical pictures
 
 
5. Engineering attachments
The attachments provide the official information of the board master and the information of the UWB module.