Application Note
page 5 of 32
V1.0
2021-03-31
Distance2GoL (Software-Controlled FMCW) low-power radar shield using
BGT24LTR11 for range detection and human tracking
Introduction
1
Introduction
The Distance2GoL radar system is a demo platform for
Infineon’s
24 GHz silicon-germanium (SiGe) BGT24LTR11
radar chipset. It consists of two boards
–
the microcontroller board: Radar Baseboard XMC4700, and a radar
front-end board: BGT24LTR11 Shield. This document focuses on the BGT24LTR11 Shield assembled for a
software-controlled Frequency Modulated Continuous Wave (FMCW) implementation. Detailed information
about the Radar Baseboard XMC4700 can be found in the corresponding application note (AN602).
The system
is designed to enable customers to carry out prototyping and system integrations as well as initial
product feature evaluations. The platform is a low-power solution for tracking human presence and detecting
range. These features of the board make it suitable for various applications such as presence sensing, proximity
sensing and motion detection. These use cases target applications such as outdoor security cameras, smart-
home devices and lighting control.
The main radar technique used on the platform is FMCW for range estimation. In FMCW, the time delay between
the transmitted and received chirp is used for measuring the distance to the target(s). The transmitted and
received signals are mixed and then quantized for further processing. A Software-Controlled loop performs the
frequency control and ramp generation. This eliminates the need for a high-cost PLL IC, hence reducing system
cost. The circuitry is designed for low power consumption. Two-stage low-noise baseband amplification stages
are used for enhanced target detection. The baseband section is configurable for different cut-off frequencies
and gain requirements of different applications. The module also offers the possibility of using a battery for
operation.
The module provides a complete radar system evaluation platform, including demonstration software and a
basic graphical user interface (GUI), which can be used to display and analyze acquired data in time and
frequency domains.
An onboard debugger with licensed firmware from SEGGER enables easy debugging over
USB. Infineon’s powerful, free
-of-
charge toolchain DAVE™ can be used for programming
the XMC4700
microcontroller. The system also features integrated micro-strip patch antennas on the PCB with design data,
thereby eliminating antenna design complexity at the user end.
This application note describes the key features and hardware configuration of the BGT24LTR11 Shield in
detail.
