Infineon AN553 User Manual

Application Note Please read the Important Notice and Warnings at the end of this document V1.3

www.infineon.com page 1 of 38 2020-05-05

AN553

24 GHz transceiver - BGT24MTR12

P osi t i o n2 G o – XE NS IV ™ 24 G Hz r ad ar d em o k i t w it h
B GT 24 MT R1 2 an d X M C4 70 0 32 - b it A R M ® C o r t e x™ -M 4 MC U fo r
r an gi n g , mo ve me nt a nd t a r g et p o s i t io n es ti ma ti on

B o ar d v er s i on V 1 . 2

About this document

Scope and purpose

This application note describes the key features of Infineon’s Position2Go module equipped with the 24 GHz
transceiver chip BGT24MTR12 and the 32-bit ARM® Cortex™-M4 based XMC4700 microcontroller and helps the
user to quickly get started with the demo board.

1. The application note describes the hardware configuration and specifications of the sensor module in

detail.

2. It also provides a guide to configure the hardware and implement simple radar applications with the

firmware/software developed.

Intended audience

This document serves as a primer for users who want to get started with hardware design for target position
estimation using the Frequency Modulated Continuous Wave (FMCW) radar technique at 24 GHz.

Related documents

Additional information can be found in the supplementary documentation provided with the Position2Go Kit in
the Infineon Toolbox or from www.infineon.com/24GHz:

 24 GHz Radar Tools and Development Environment User Manual
 P2G Software User Manual

Application Note page 2 of 38 V1.3
2020-05-05

Table of contents

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

Table of contents

About this document ....................................................................................................................... 1

Table of contents ............................................................................................................................ 2

List of figures ................................................................................................................................. 3

List of tables .................................................................................................................................. 4

1 Introduction .................................................................................................................. 5

1.1 Key features ............................................................................................................................................. 6

2 Getting started .............................................................................................................. 7

2.1 Additional material ................................................................................................................................. 9

3 System specifications .................................................................................................... 10

4 Hardware description ................................................................................................... 12

4.1 Overview ................................................................................................................................................ 12

4.2 Hardware features ................................................................................................................................. 13

4.3 Block diagram ........................................................................................................................................ 14

4.4 Power supply ......................................................................................................................................... 16

4.5 RF front end ........................................................................................................................................... 17

4.5.1 Board stack-up ................................................................................................................................. 17

4.5.2 BGT24MTR12 – 24 GHz transceiver MMIC ........................................................................................ 18

4.5.3 Module transmitter section ............................................................................................................. 19

4.5.4 Module receiver section ................................................................................................................... 19

4.5.5 Antennas ........................................................................................................................................... 20

4.6 Prescaler output and PLL section ......................................................................................................... 20

4.7 Analog baseband section ...................................................................................................................... 22

4.7.1 Gain settings ..................................................................................................................................... 23

4.7.2 IF section and FMCW ramp setting .................................................................................................. 24

4.8 Duty-cycle circuit for low-power operation (default mode) ................................................................ 25

4.9 External pin header connectors ............................................................................................................ 26

4.10 Microcontroller unit – XMC4700 ............................................................................................................ 28

4.11 Onboard debugger and UART connection ........................................................................................... 28

4.12 User LEDs ............................................................................................................................................... 29

5 Measurement results..................................................................................................... 30

5.1 Measurement default configuration ..................................................................................................... 30

5.2 Maximum distance measurement ........................................................................................................ 30

5.3 Range accuracy measurement ............................................................................................................. 31

5.4 Angular accuracy measurement ........................................................................................................... 32

5.5 Temperature chamber measurement .................................................................................................. 33

6 Frequency band and regulations .................................................................................... 34

6.1 24 GHz regulations ................................................................................................................................ 34

6.2 Regulations in Europe ........................................................................................................................... 34

6.3 Regulations in the United States of America ........................................................................................ 34

7 Authors ........................................................................................................................ 35

8 References ................................................................................................................... 36

Revision history............................................................................................................................. 37

Application Note page 3 of 38 V1.3
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List of figures

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

List of figures

Figure 1 Steps 1 to 3 to get started with Position2Go demo board ................................................................. 7

Figure 2 Steps 4 to 6 to get started with Position2Go demo board ................................................................. 8

Figure 3 Steps 7 to 9 to get started with Position2Go demo board ................................................................. 9

Figure 4 Position2Go board with main components and dimensions .......................................................... 12

Figure 5 Block diagram – Position2Go demo board....................................................................................... 15

Figure 6 Block diagram – power supply concept ........................................................................................... 16

Figure 7 RF front end overview (top) .............................................................................................................. 17

Figure 8 PCB cross-section .............................................................................................................................. 17

Figure 9 Block diagram – BGT24MTR12 .......................................................................................................... 18

Figure 10 Transmitter section schematic and matching structure dimensions ............................................. 19

Figure 11 Receiver section schematic and matching structure dimensions................................................... 19

Figure 12 2D radiation pattern for array antennas........................................................................................... 20

Figure 13 Block diagram for PLL control loop .................................................................................................. 21

Figure 14 PLL section overview with loop filter components .......................................................................... 22

Figure 15 Baseband amplifier chain on PCB .................................................................................................... 22

Figure 16 PGA gain plots for different settings ................................................................................................. 24

Figure 17 BGT24MTR12 duty-cycle concept ..................................................................................................... 25

Figure 18 Duty-cycle vs. no duty-cycle current consumption ......................................................................... 26

Figure 19 Position2Go external header pin overview ...................................................................................... 26

Figure 20 Block diagram – XMC4700 ................................................................................................................. 28

Figure 21 Recommended installation options for the J-Link driver ................................................................ 28

Figure 22 Breakable onboard debugger section .............................................................................................. 29

Figure 23 Maximum distance vs. AoA................................................................................................................ 30

Figure 24 Range accuracy for 1 m2 corner reflector target .............................................................................. 31

Figure 25 Angular accuracy for 1 m2 corner reflector target ............................................................................ 32

Figure 26 Temperature measurement at 25°C (markers at 24.000 GHz and 24.250 GHz) .............................. 33

Figure 27 Temperature measurement at 85°C (markers at 24.000 GHz and 24.250 GHz) .............................. 33

Figure 28 Temperature measurement at -35°C (markers at 24.000 GHz and 24.250 GHz) ............................. 33

Application Note page 4 of 38 V1.3
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List of tables

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

List of tables

Table 1 Position2Go module performance specifications ........................................................................... 10

Table 2 PLL loop filter components and values ............................................................................................ 21

Table 3 PLL pin description ............................................................................................................................ 21

Table 4 Baseband amplifiers to MCU pin connections ................................................................................. 23

Table 5 IF BB section gain settings ................................................................................................................ 23

Table 6 IF frequency vs. FMCW ramp parameters vs. target distance .......................................................... 24

Table 7 External headers – pin description ................................................................................................... 27

Table 8 XMC4200 pins used for debugging and UART communication ....................................................... 29

Table 9 User LEDs pin assignment ................................................................................................................. 29

Application Note page 5 of 38 V1.3
2020-05-05

Introduction

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

1 Introduction

The Position2Go Kit is a demonstration platform for Infineon’s silicon-germanium (SiGe) based 24 GHz
BGT24MTR12 radar chipset. The board is capable of measuring distance, speed, direction of movement and
Angle of Arrival (AoA). These features of the board make it suitable for various applications such as tracking
humans, presence detection, collision avoidance, etc.

The Position2Go board consists of the following key components:

 BGT24MTR12 – highly integrated 24 GHz transceiver IC with one transmitter (TX) and two receivers (RX)
 XMC4700 – 32-bit ARM® Cortex™-M4 based microcontroller for signal processing
 IRLHS2242 – 20 V single P-channel HEXFET power MOSFET for duty-cycle operation
 XMC4200 onboard debugger – licensed firmware for Serial Wire Debug (SWD) and UART to USB

communication

The main radar technique used on the board is FMCW. In this technique, the time delay between the
transmitted and received chirp is used for measuring distance to the target(s). The transmitted and received
signals are mixed and then quantized for further processing. Multiple chirps (up to 16) are processed in order to
create a 2D range-Doppler map to estimate the distance and the velocity of the target(s). Since the MMIC has
two receivers, a phase monopulse comparison technique is used to determine the AoA.

The module provides a complete radar system evaluation platform including demonstration software and a
graphical user interface (GUI) that can be used to display and analyze acquired data in time and frequency
domain. An onboard breakable debugger with a licensed firmware from SEGGER enables easy debugging over
USB. Infineon’s powerful, free-of-charge toolchain DAVE™ can be used to program the XMC4700
microcontroller. The board also features integrated micro-strip patch antennas on the PCB, including the
design data, thereby eliminating antenna design complexity at the user end.

This application note describes the key features and hardware configuration of the Position2Go module in
detail.

Application Note page 6 of 38 V1.3
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Introduction

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

1.1 Key features

The primary features of the Position2Go board are:

 Detect and track position of multiple targets in outdoor environments
 Measure distance of multiple targets in a user-configurable range (1 to 50 m)
 Detect motion, presence, speed and direction of movement (approaching or retreating) for human

targets

 Small form factor: 5 x 4.5 cm
 Operational in different weather conditions such as rain, fog, etc.
 Can be hidden in the end application as it detects through non-metallic materials
 Dual analog amplifier stages for each RX channel with user-configurable gain settings
 Micro-strip patch antennas with 12 dBi gain and 19 x 76 degrees Field of View (FoV)
 Onboard PMOS switch for duty-cycle operation and low power consumption

Note: The platform serves as a demonstrator platform with the software to perform simple motion sensing,

ranging and tracking. The test data in this document show typical performance of Infineon-produced
platforms. However, board performance may vary depending on the PCB manufacturer and specific design
rules they may impose and components they may use.

Application Note page 7 of 38 V1.3
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Getting started

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

2 Getting started

This section provides a step-by-step quick process to get started with the Position2Go board. Some of the steps
are optional for going deeper into the analysis of the board, the firmware and the extracted signals.

STEP 1

STEP 2

ST EP 3

Box contents

• Programmed Position2Go

board

• Micro-USB cable

• Foldable corner reflector

Infineon Toolbox

• Go to:

www.infineon.com/Toolbox

• Click on “Download now”

button.

• Run “infineon-toolbox-

launcher-web-installer-win­x86-latest.exe” file.

• “Accept” the license

agreement.

• Finish installation. Create a

desktop shortcut.

Install Position2Go Kit

• Open “Infineon Toolbox”.

• Click on “Manage tools” tab.

• Search for “Position2Go Kit”.

• Click on “Install”.

• “Accept” the license

agreement.

• Finish installation.

Figure 1 Steps 1 to 3 to get started with Position2Go demo board

Application Note page 8 of 38 V1.3
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Getting started

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

STEP 4

STEP 5

ST EP 6

Download SW/HW package

• Open “Infineon Toolbox”.

• Click on “Position2Go Kit”.

• Download the package from

“Software & Documentation”
left tab.

• Save the set-up file and run

it.

• Browse to preferred location

to store the files.

Connect board

• Insert micro USB cable into

Position2Go (main board).

• Insert the USB connector

into PC USB port.

 If the device driver is not

recognized:

Right click on “My Computer” 
Manage  Device Manager 
Other devices  Right click on
“Unknown device”  Update
Driver Software  Browse 
Firmware_Software 
XMC_Serial_Driver.

Firmware (FW) update

• Download and install

SEGGER J-Link USB drivers
for Windows:

• Connect USB cables on

both sides (main board and
debugger).

• Open Infineon Toolbox 

XMC Flasher.

• Check that debugger type is

“SEGGER”, otherwise go to:
“Configurations”  “Setup”,
then set it to “SEGGER”.

• Click on “Connect” 

XMC4700-2048.

• Click on “Select file” 

Browse to

Firmware_Software  Binary

 .hex file  Program.

Figure 2 Steps 4 to 6 to get started with Position2Go demo board

P2G-HW-SW.exe

www.segger.com/download
s/jlink/#J­LinkSoftwareAndDocument
ationPack

Optional

Optional

Application Note page 9 of 38 V1.3
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Getting started

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

STEP 7

STEP 8

ST EP 9

View and edit source code

• Download and install

DAVE™ IDE tool:

• Go to Firmware_Software 

DAVE project.

• Run DAVE™ IDE.

• Import DAVE™ projects and

debug.

Radar GUI

• Connect board as STEP 5.

• Open Infineon Toolbox 

Radar GUI.

• Real-time data is now

visible on your screen.

MATLAB interface

• Go to: Firmware_Software 

Communication Library 
ComLib_Matlab_Interface 
RadarSystemExamples 

GettingStarted. Copy the path.

• Open MATLAB. Paste the path

in the top tab.
“extract_raw_data.m” file will
show up on the left tab.

• Connect board as STEP 5.

• Click on “Run” to see raw data.

Figure 3 Steps 7 to 9 to get started with Position2Go demo board

2.1 Additional material

The board comes with additional documentation for customer support. These documents can be found in the
folders downloaded through Step 4 in Figure 2. They are:

 Altium project
 DAVE™ project and binary files
 Software user manual
 ComLib documentation
 Schematics
 Bill of Materials (BOM)
 Production data

Optional

https://infineoncommunity
.com/dave­download_ID645

Optional

Application Note page 10 of 38 V1.3
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System specifications

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

3 System specifications

Table 1 gives the specifications of the Position2Go module.

Table 1 Position2Go module performance specifications

Parameter

Unit

Min.

Typ.

Max.

Comments

System performance

Minimum speed

km/h

0.7

Based on the formula:
Min speed (m/s) =  /(2 





 )

in P2G_FMCW firmware

 = wavelength (m)




= DOPPLER_FFT_SIZE

 = Pulse Repetition Time

Maximum speed

km/h

22.4

Based on the formula:
Max speed (m/s) =  /(4  )
in P2G_FMCW firmware

 = wavelength (m)

 = Pulse Repetition Time

Minimum distance

cm 60

Radar Cross-Section (RCS) = 1 m²

Maximum distance

m 15

RCS = 1 m

2

(based on 100 LSB

range detection threshold)

Range accuracy (for values
beyond 60 cm)

cm ±20

RCS = 1 m2

Range resolution

cm 90

With Blackman window
(BW 200 MHz, 300 µs ramp up, 64

samples/chirp, 256 FFT size)

Angle accuracy

Degrees

≤ 5

FoV +/-30 degrees
RCS = 1 m2 at 3 m range

Degrees

≤ 10

FoV +/-65 degrees
RCS = 1 m2 at 3 m range

Power supply

Supply voltage

V

3.3 5 5.5

Supply current

mA 420

All blocks on (no duty-cycle)

Transmitter characteristics

Transmitter frequency

GHz

24.0

24.25

Effective Isotropic Radiated Power
(EIRP)

dBm 18

EIRP controllable via SPI for ISM
operation

System phase noise with PLL

dBc/Hz

-89

At 100 kHz offset, VCOARSE =
VFINE. Measured in CW mode

External oscillator frequency

MHz 40

Application Note page 11 of 38 V1.3
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System specifications

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

Table 1 Position2Go module performance specifications

Parameter

Unit

Min.

Typ.

Max.

Comments

Receiver characteristics

Receiver frequency

GHz

24.0

24.25

IF conversion gain
(Stage 1)

dB 23.5

-3dB bandwidth
(Stage 1)

kHz

14 to

140

Can be selected by reconfiguring
the ADC pins in DAVE™ project

IF conversion gain
(Stage 1 + Stage 2)

dB

23.5

47.5

65.5

Configurable by PGA SPI settings
of Stage 2

-3dB bandwidth
(Stage 1 + Stage 2)

kHz

13 to

105

Default setting of the sensor
module when delivered

Antenna characteristics (measured)

Antenna type (TX/RX)

1 x 6

Horizontal – 3dB beamwidth

Degrees

76

Elevation – 3dB beamwidth

Degrees

19

Horizontal sidelobe level
suppression

dB 20

Vertical sidelobe level suppression

dB 20

Note: The above specifications are indicative values based on typical datasheet parameters of BGT24MTR12 and

simulation of several other parameters (antenna characteristics and baseband section) and can vary from
module to module. The numbers above are not guaranteed indicators for module performance for all
operating conditions.

Application Note page 12 of 38 V1.3
2020-05-05

Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

4 Hardware description

4.1 Overview

The Position2Go module contains a radar main board and a breakable debugger board as shown in Figure 4.
The radar main board contains four important sections:

 RF part – consists of the Infineon 24 GHz radar MMIC – BGT24MTR12 and the tapered micro-strip patch

antennas for the TX and RX sections;

 Analog amplifier part – provides the interface between the RF and digital parts of the board. It has

programmable gain amplifiers (PGAs), which can be programmed over the SPI to provide variable gains
for different use cases;

 Frequency control part – contains a low-noise fractional-N PLL;
 Digital part – consists of a XMC4700, 32-bit ARM® Cortex™-M4 microcontroller from Infineon to sample

and process the analog data from the radar front end and also to configure the BGT24MTR12, PLL and

PGAs via an SPI.
The board demonstrates the features of the BGT24MTR12 RF front-end chip and gives the user a complete
“plug and play” radar solution. It makes it possible to quickly gather sampled radar data that can be used to
develop radar signal-processing algorithms on a PC or implement target detection algorithms directly on the
microcontroller using DAVE™.

50 mm

45 mm

15 mm

Debugger board
(breakable)

Main board

(RF front-end + MCU)

Tx Patch
Antenna

Rx Patch
Antenna

BGT24

MTR12

XMC4700

PLL

PGA (BB Section)

FOV:

19°x76°

Figure 4 Position2Go board with main components and dimensions

Application Note page 13 of 38 V1.3
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Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

4.2 Hardware features

The Position2Go demo board has the following features:

 BGT24MTR12 24 GHz RF front-end chip with 1 TX and 2 RX with the following specification:

o Low Noise Figure (NF

SSB

): 12 dB

o High conversion gain: 26 dB
o High 1 dB input compression point: -12 dBm
o Switchable prescaler with 1.5 GHz and 23 kHz output
o On-chip power and temperature sensors

 XMC4700 Cortex-M4 microcontroller for sampling and signal processing of the analog signals with the

following features:

o 144 MHz CPU frequency, 2048 kB Flash and 352 kB RAM size
o Four Capture and Compare Units (CCU4) for use as general-purpose timers
o Four 12-bit ADCs, 26 channels each with input out-of-range comparators, and a 12-bit DAC with

two channels

o USB 2.0 device, with integrated PHY, Controller Area Network interface (MultiCAN), Full-

CAN/Basic-CAN with six nodes, 256 message objects (MOs), data rate up to 1 MBaud

o Six Universal Serial Interface Channels (USICs), providing six serial channels, usable as UART,

double-SPI, quad-SPI, I2C, I2S and LIN interfaces

 Onboard breakable debugger with UART communication
 Onboard low-noise fractional-N PLL with chirp generation
 Dual analog amplifier stage for each RX channel with programmable gain settings
 Micro-strip patch antennas with 12 dBi gain(simulated) and 19 x 76 degrees FoV
 Onboard PMOS switch for duty-cycle operation of BGT24MTR12
 Power supply:

o Via micro-USB connector
o Via external power supply (5 V maximum)

Application Note page 14 of 38 V1.3
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Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

4.3 Block diagram

Figure 5 shows the block diagram of the demo board. The board is split into a main RF unit and a breakable
debugger unit for programming. The RF unit consists of the highly integrated 24 GHz transceiver IC
BGT24MTR12 with 1 TX and 2 RX. The MMIC features an integrated Voltage Controlled Oscillator (VCO), Power
Amplifier (PA), integrated temperature and power sensors, prescalers and IQ receivers.

The board also has integrated micro-strip patch antennas, and a Wilkinson combiner is used to combine the
differential transmitter output power from the radar IC before feeding it to the antennas. Each receiver channel
is connected to a dual analog amplifier stage at its IF outputs. A 32-bit ARM® Cortex™-M4 XMC4700
microcontroller is used to sample and process the analog down-converted signals from the baseband
amplifiers using the integrated 12-bit ADC, and also control the radar chip via the SPI interface. The output
power of the radar chip and the gain of its receive section can be controlled via the SPI settings. There are also
SPI commands to read out the different sensor outputs.

A low-noise fractional-N Phase Locked Loop (PLL) IC is used to perform the frequency control and ramp
generation. The output of the /16 prescaler on the radar IC is connected to the PLL’s RF input pins and the
output voltage from the PLL’s charge pump is connected via a loop filter to the tuning ports of the
BGT24MTR12, thereby forming a closed-loop system. This procedure is used to lock the transmitted signal of
the module to an output frequency inside the ISM band. The /65536 prescaler produces a low-frequency output
signal (23 kHz), which is connected to a CCU4 of the XMC4700 for monitoring purposes.

The module is powered over the micro-USB plug, and several low-noise voltage regulators are used to provide
a regulated power supply to the different building blocks .The BGT24MTR12 MMIC is supplied over a PMOS
switch, which enables operation of the sensor in a duty-cycle mode. The Position2Go features a breakable
onboard debugger, which comes preloaded with licensed firmware for debugging and communicating with the
main radar MCU via the UART pins. Pin headers on the PCB enable the sensor module to interface with an
external processor.

Application Note page 15 of 38 V1.3
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Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

Figure 5 Block diagram – Position2Go demo board

Application Note page 16 of 38 V1.3
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Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

4.4 Power supply

Figure 6 shows the power supply concept used on the module. The board is powered via micro-USB connector
when used with a PC. The power supply is via an external DC input pin (5 V maximum). The USB plugs on the
main board as well as the breakable debugger board can be used to supply the module.

Figure 6 Block diagram – power supply concept

The power supply via the USB or external input is provided to four different voltage regulators. The 24 GHz
transceiver IC is powered by a low-noise voltage regulator U23. U23 has an enable pin that must be triggered
via the pin P1.4 of the MCU to enable the LDO. Regulator U20 is also used to supply the analog domain of the
XMC4700 MCU and the first baseband IF amplifier stage. A second low-noise voltage regulator U3 is used to
supply the digital MCU of the board. U4 is used to power up the PLL and the 40 MHz reference oscillator. The
enable pins of U3 and U4 are hardwired to their input voltage pins on the PCB and are not available to the user.
Additionally, another low-noise regulator U28 is used to supply the PGA.

Application Note page 17 of 38 V1.3
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Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

4.5 RF front end

Figure 7 shows the top view of the RF front end. The RF front end can be shielded with a cover and absorber
material to get the best RF performance. The following paragraph describes the various sections of the RF front
end in detail.

DC Blocks

2nd Harmonic

Filter

Wilkinson
Combiner

BGT24MTR12

TX Side RX Side

Figure 7 RF front end overview (top)

4.5.1 Board stack-up

It is necessary to use a defined board layer stack-up for proper functioning of the RF part. All the micro-strip RF
parts must be calculated according to the stack-up used. The cross-sectional view of the PCB is shown in Figure

8. The module uses six-layer stack-up with a symmetrical RO-4350B core. The matching structures for the
transmitter and receiver parts are designed based on this stack-up.

Cu - 35µm

Vias

Ro4350B, 0.254 mm

FR4, 0.150 mm
FR4, 0.150 mm

FR4, 0.100 mm

Ro4350B, 0.254 mm

Cu - 18µm

Cu - 35µm

Figure 8 PCB cross-section

The most important part for the RF micro-strip components is the top and bottom RO-4350B, 0.254 mm-thick
core. On the top layer (layer 1) are the micro-strip structures, and layer 2 is the RF ground for the micro-strip
components used on the top layer. Layer 3 and layer 4 are used for routing various signals. On the bottom layer
(layer 6) are the micro-strip patch antennas and layer 5 is the RF ground for the micro-strip patch antennas. The
substrate thickness for the other layers have been chosen taking into account the blind-via diameters used on
the PCB, and this can vary depending on the PCB manufacturing technology (aspect ratio). From simulations it
was observed that such variation of the thickness of these FR4 substrates has a very low impact on the RF
performance.

Application Note page 18 of 38 V1.3
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Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

4.5.2 BGT24MTR12 – 24 GHz transceiver MMIC

The heart of the sensor module is the highly integrated BGT24MTR12 24 GHz transceiver IC. Figure 9 shows the
detailed block diagram of the MMIC.

Figure 9 Block diagram – BGT24MTR12

The MMIC features a very high level of integration, which includes a VCO with prescaler outputs for frequency
control, transmitter chain including amplifiers for both TX and LO outputs, and dual receiver section with Low­Noise Amplifiers (LNAs) and mixers. The dual receive channels help to determine the AoA of the signal from the
radar target.

The VCO is a free-running, fundamental oscillator. It can be controlled by two tuning inputs – one for coarse
preadjustment, and one for fine-tuning. There are two prescalers available in the VCO section of the chip. The
first prescaler has an output frequency of 1.5 GHz and can be used to feed an RF-PLL for frequency control. The
second prescaler has a 23 kHz square-wave output that may be used by a microcontroller-based software loop.

The TX section consists of a power amplifier with a differential output. Its typical output power is +11 dBm and
can be reduced in eight steps down to 2 dBm. A part of the TX signal is used as the LO signal for the on-chip
mixers. The receiver sections have a single-sideband NF of 12 dB and a voltage conversion gain of 26 dB. The
gain of the LNA can be reduced by a typical gain-step of 5 dB. The built-in quadrature down-conversion mixers
translate the RF signal directly to zero-IF.

Additionally, the chip features power sensors on both TX outputs and LO outputs, as well as a temperature
sensor that supports the implementation of a software-based loop to control the VCO. The settings of the
different internal building blocks can be controlled via an SPI.

SPI

Buffer

/16

TX

PA

/65536

3

TX

Power

Sensor

Temp.

Sensor

PPF*

LNA

IFI1

IFQ1

90°

0°

RFIN1

LO

Buffer

MPA

IFQX1

IFIX1

* Poly Phase Filter

FINE

COARSE

Q2

SI CS CLK

LO

POWER

SENSOR

AMUX

2

2

ANA

PPF*

LNA

IFI2

IFQ2

90°

0°

RFIN2

LO

Buffer

IFQX2

IFIX2

Q1

TXX

Application Note page 19 of 38 V1.3
2020-05-05

Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

4.5.3 Module transmitter section

The transmitter output of BGT24MTR12 is differential. The differential outputs are first connected over
matching structures followed by a Wilkinson power combiner. The matching structures compensate for the
bondwire inductance and other parasitic effects due to the VQFN package. Figure 10 shows the schematic of
the transmitter section and the dimensions of the matching structures used at the TX outputs. The Wilkinson
power combiner combines the differential signals into single-ended ones. Following the power combiner a
second harmonic micro-strip filter is used. The harmonic filter provides an attenuation greater than 20 dB for
frequencies around 48 GHz and shows a simulated loss of approximately 0.5 dB. The filter path then goes over a
DC block and a feed-through via to the other side of the PCB to the antennas. The simulated loss for the entire
RF section connecting the TX output from the MMIC to the antennas on the other side of the board including the
vias was approximately 2 dB. There are DC shorts before the feed-through vias for enhanced ESD protection.

B) TX Matching Structures

In [mm]

TXX

TX

A) Schematic – Transc eiver Section

100Ω

Figure 10 Transmitter section schematic and matching structure dimensions

4.5.4 Module receiver section

The receiver input of the BGT24MTR12 is single-ended. The RX input is connected over a matching structure, a
DC block and a feed-through via to the antennas on the other side of the board. Figure 11 shows the schematic
of the receiver section and the dimensions of the matching structures used at the RX input. The simulated loss
for the entire RF section connecting the RX input at the MMIC to the antennas on the other side of the board
including the vias was approximately 1 dB. There are DC shorts before the feed-through vias for enhanced ESD
protection.

A) Schem atic – Receiver Section

B) RX M atching Struc tures

In [mm]

Figure 11 Receiver section schematic and matching structure dimensions

Application Note page 20 of 38 V1.3
2020-05-05

Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

4.5.5 Antennas

Position2Go features a 6 x 1 series-fed tapered array antenna for the transceiver and receiver sections. The
antenna has a measured gain of 12 dBi (simulated) and an opening angle of 19 x 76 degrees. Figure 12 shows
the measured 2D radiation pattern.

Figure 12 2D radiation pattern for array antennas

It must be noted that the values of 19 x 76 degrees are for 3 dB Half Power Beamwidth (HPBW). This implies that
the gain of the antenna beyond these angles is 3 dB lower than the maximum gain at 0 degrees. In practical
cases, a target with large RCS can still be detected for this reduced gain. In addition, weaker targets (i.e., low
RCS) in close proximity to the radar can also be detected outside the opening angles. Therefore, a careful
judgement has to be made regarding the radar detection zone by taking into account both distance of target
from radar and also the target RCS.

4.6 Prescaler output and PLL section

BGT24MTR12 has two prescaler outputs: Q1 and Q2. Q1 represents the VCO output divided by a factor of 24. Q2
represents the VCO output divided by a factor of 220. As shown in Figure 13, the Q1 output is connected to the RF
input terminal of a low-noise fractional-N PLL LMX2491 with integrated ramp/chirp generation functionality.
The prescaler output from the MMIC is DC-coupled via capacitor C27.

The VCO can be controlled by DC inputs on two different pins: VCOARSE (Pin 6) and VFINE (Pin 5) of the
BGT24MTR12. The VCOARSE and VFINE pins are tied together and connected to the PLL’s charge pump output
voltage (CP

out

) via a loop filter circuit. The loop filter has been optimized for an FMCW ramp of 300 µs. A 40 MHz
reference oscillator is used as the clock source for the PLL. Table 2 lists the loop filter components with their
values.

Schematics with more detailed information can be downloaded from the Infineon Toolbox (refer to Figure 2).

Application Note page 21 of 38 V1.3
2020-05-05

Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

Figure 13 Block diagram for PLL control loop

Table 2 PLL loop filter components and values

Component

Value

C23

33 nF

C22

2.2 nF

C37, C38

150 pF

R23

820 kΩ

R25

120 Ω

The current firmware version provided with the module is optimized and tested with sawtooth ramps of 300 µs.
In principle, use of other ramp types (e.g. triangular) and other ramp durations should also be possible.
However this is not tested using the hardware/firmware configurations provided and may require
reconsidering other system timing settings (e.g. duty-cycle, waiting times, etc.) and baseband section
modification.

For the optimized PLL settings, refer to the DAVE™ project delivered with the Infineon Toolbox. Please refer to
Step 4 in Figure 2 for further download information. Apart from the SPI pins, Table 3 lists the other PLL pins
accessible on the module via the MCU for various configuration settings.

Table 3 PLL pin description

Pin number – PLL

Description

Functionality

MCU pin connection

Pin 12

MOD

Multiplexed input/output pins for ramp triggers,
FSK/PSK modulation, FastLock, and diagnostics

P1.2
Pin 13

CE

Chip enable

P2.2

Pin 17

MUXOUT

Multiplexed input/output pins for ramp triggers,
FSK/PSK modulation, FastLock, and diagnostics

P1.0

Pin 20

TRIG 1

Multiplexed input/output pins for ramp triggers,
FSK/PSK modulation, FastLock, and diagnostics

P1.3

Pin 21

TRIG 2

Multiplexed input/output pins for ramp triggers,
FSK/PSK modulation, FastLock, and diagnostics

P1.1

The Q2 prescaler output from the BGT24MTR12 is 23 kHz and this is fed into the CCU4 of the XMC4700 MCU. This
can be used to keep the VCO inside the ISM band by controlling the tuning voltage pins via the MCU’s DAC. This
procedure would eliminate the need for hardware PLL but requires complex ramp generation, linearization

Application Note page 22 of 38 V1.3
2020-05-05

Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

techniques and signal processing algorithms for proper target detection. The Position2Go board is designed to
implement this functionality if one desires to do so. However, Infineon currently does not provide firmware,
supporting such software-based ramp generation for distance measurements. When using the Q2 output, it is
very important to keep the Q1 output terminated with a DC block to obtain a proper Q2 signal at the
microcontroller timer input. It is recommended to keep the Q2 divider off during signal processing to prevent
unwanted spurs and baseband noise.

BGT24MTR12XMC4700 LMX2491 PLL

R25

C22

C23

R23

C37

C38

A) PLL Section - Components B) Loop Filter Components

Reference Osc

40MHz

Figure 14 PLL section overview with loop filter components

4.7 Analog baseband section

The BGT24MTR12 provides both in-phase and quadrature-phase Intermediate Frequency (IF) signals from each
of its receive channels. The in-phase and quadrature-phase signals are differential in nature, thus making
available four different IF output signals from each receive channel (IFI, IFIx, IFQ and IFQx). Depending on the
target in front of the radar antennas, the analog output signal from the BGT24MTR12 chipset can be very low in
amplitude (µV to mV range). To process these low-amplitude signals it is necessary to amplify the IF signals that
come out of the RF front end with analog amplifiers.

Figure 15 Baseband amplifier chain on PCB

The Position2Go module enables the user to select either the low gain (first stage only) or high gain (first stage
+ second stage) mode depending on the target RCS and the distance to be detected by simply configuring the
MCU pin settings in the software. No hardware changes are needed for this process. Table 4 lists the MCU pins
associated with each of the gain stages. Use the graphical pin select tool in the DAVE™ software to select the
appropriate pins for signal processing.

IF1_I

IF1_Ix

IF1_Q

IF1_QX

IF2_I
IF2_Ix
IF2_Q

IF2_QX

Baseband Section – Position2Go

U26

OPA2376

U27

OPA2376

IF1I_HG

IF1Q_HG

IF2I_HG

IF2Q_HG

IF1I_LG

IF1Q_LG

IF2I_LG

IF2Q_LG

U25

PGA112

U33

PGA112

U29

PGA112

U30

PGA112

Stage 1 Stage 2

U26

U27

U25

U33

U29
U30

A) Concept – Baseband Section B) Baseband Components

Application Note page 23 of 38 V1.3
2020-05-05

Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

Table 4 Baseband amplifiers to MCU pin connections

XMC4700 – BGA196 – port pin

Pin function

P14.4

IF1I – high gain

P14.14

IF1Q – high gain

P15.3

IF2I – high gain

P15.8

IF2Q – high gain

4.7.1 Gain settings

The Position2Go module has a two-stage baseband amplification process. The first stage is designed with an
operational amplifier with fixed gain and cut-off frequency settings. The second stage has PGAs to adjust the
gains easily using SPI.

The baseband section of the Position2Go module is designed to have a bandpass characteristic. Due to limited
isolation between the TX and RX of the radar system, there is a feed-through of the TX signal into the RX part.
Consequently, there is always a dominant low-frequency component at the receiver output of the radar IC. The
value of this low-frequency component depends on the value of the FMCW ramp settings. This low-frequency
signal will be further amplified by the gain of the baseband section and may completely saturate the radar IF
chain (ADCs and further amplifier stages). This effect is inherent to all FMCW radar systems and cannot be
eliminated completely in the analog domain. The TX-to-RX cross-talk effect also limits the minimum distance
that can be measured by the radar. However, by using appropriate filtering, the effect of this cross-talk can be
minimized. This requires the implementation of filtering stages prior to the amplification of the IF signal by the
baseband section.

Stage 1 is designed for a gain of 23.5 dB with a 3 dB bandwidth from 14 kHz to 140 kHz. The second IF amplifier
stage consists of a programmable gain amplifier, and in combination with the first IF stage provides a total IF
gain of maximum 65.5 dB with a 3 dB bandwidth from 13 kHz to 105 kHz.

Table 5 IF BB section gain settings

GUI setting

Binary gain

PGA gain (dB)

Total BB section gain (dB)

Max.

128

42

65.5

L6

64

36

59.5

L5

32

30

53.5

L4

16

24

47.5 (default setting)

L3 8 18

41.5

L2 4 12

35.5

L1 2 6

29.5

Min. 1 0

23.5

Application Note page 24 of 38 V1.3
2020-05-05

Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

Figure 16 PGA gain plots for different settings

For short-range measurements (less than 10 m) it is sufficient to use only a single IF amplification stage. The
PGAs can be removed for this range, thereby reducing the BOM cost. For long-range measurements (more than
10 m), and for targets with very low and varying RCS (e.g. human beings) the radar may not be able to provide a
precise detection, depending on the environmental condition.

4.7.2 IF section and FMCW ramp setting

The bandpass characteristics of the IF section are also determined from the FMCW ramp parameter settings.
Different ramp settings lead to different IF frequencies for targets at different distances. Table 6 gives an
example of IF frequencies produced by stationary targets at particular distances corresponding to different
sawtooth-type ramp parameters. These IF frequencies are also called as “beat frequencies”. The beat
frequencies calculated in the table do not include the Doppler shift.

The 󰇛󰇜 is calculated from the following formula:

󰇛󰇜 

    

  



Where

 = target distance in meter (m)

 = ramp bandwidth in Hertz (Hz)

 = ramp time in second (s)

 = speed of light in meter/second (m/s)

Table 6 IF frequency vs. FMCW ramp parameters vs. target distance

Ramp duration
(µs)

Ramp
bandwidth
(MHz)

Beat frequency (kHz)

Target at 0.5 m

Target at 5 m

Target at 10 m

Target at 25 m

300

180 2 20

40

100

300

200

2

22

44

111

400

180 2 15

30

75

400

200

2

17

33

83

500

180 1 12

24

60

500

200

1

13

27

67

Application Note page 25 of 38 V1.3
2020-05-05

Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

4.8 Duty-cycle circuit for low-power operation (default mode)

The Position2Go module offers the possibility of operating the BGT24MTR12 and PLL in a duty-cycle mode. This
is done by enabling/disabling the PMOS (Q1) over the pin P2.3 of the MCU, as shown in Figure 17. Toggling this
pin enables switching the power supply on/off to the MMIC over the FET. The signal is low-active and has a pull­down resistor in place. The PLL is switched on/off using the CE pin. In its default state, the module is already
programmed for the duty-cycle mode of operation.

To enable the operation of BGT24MTR12, the trigger pin of LDO U23 connected to the MCU port pin P4.3 must
be configured first. This is already implemented in the default software. Care must be taken when changing
anything on the firmware, and it must be ensured that the LDO U23 is enabled via the MCU pin P4.3.

It is recommended to use the module in a duty-cycle mode to keep the overall power consumption and thermal
dissipation low. Position2Go was designed to have a compact form factor. Keeping the BGT24MTR12 always
turned on will heat up the module significantly and could result in undefined behavior. In such cases it is
recommended to turn off all the unused building blocks inside the BGT24 via the SPI, and for short distance
measurements reduce the transmit output power to minimum. Also putting the microcontroller in a deep sleep
mode when it is not in operation will help to minimize power consumption and thermal dissipation
significantly. The current firmware does not include the settings to put the microcontroller in a power­optimized mode.

Figure 17 BGT24MTR12 duty-cycle concept

The module also offers a second possibility to turn off the BGT24MTR11 and the IF section by using the LDO
trigger pins. The BGT24MTR12 and the baseband stage 1 consisting of U26 and U27 can be turned off by
disabling the LDO U23. This will also turn off the reference voltage generator IC U24. The PGAs can be turned
OFF by disabling the LDO U28 via pin P7.11 of the MCU. It must be noted that this mode requires detailed timing
analysis for proper signal processing, due to slower start-up time of the LDO and baseband amplifiers when
compared to the PMOS. The reduction in power consumption is minimal, since the baseband amplifiers
consume very low power. The IF section is not duty-cycled in the default board configuration.

Application Note page 26 of 38 V1.3
2020-05-05

Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

Figure 18 Duty-cycle vs. no duty-cycle current consumption

As shown in Figure 18, during duty-cycle on-time the demo board typically draws 420 mA, while during the
duty-cycle off-time with deactivated BGT24MTR12 and PLL, only 180 mA. With the default configuration of 7.3
percent on-time the demo board has a typical average current consumption of 200 mA.

4.9 External pin header connectors

The Position2Go module has the provision to connect two 14-pin headers on the edges of the board as shown
in Figure 19. Table 7 describes the pins.

Figure 19 Position2Go external header pin overview

1

2

3

4

5

6

7

8

9 10

11

12

13

14

28

27

26

25

24

23

22

21

20

19

18

17

16

15

J2J1

Label Pin 1

Application Note page 27 of 38 V1.3
2020-05-05

Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

Table 7 External headers – pin description

Pin
number

Signal name

Pin description

1

SPI_CS_PLL

SPI chip select input/output – LMX2491 PLL

2

SPI_DATA_BGT_PLL

SPI master out slave input/output (BGT and PLL)

3

SPI_CLK

SPI clock input/output

4

SPI_CS_BGT

SPI chip select input/output – BGT24MTR12

5

BGT_Q2

BGT24MTR12 Q2 prescaler output – 23kHz

6

UART-TXD

Transmit pin for UART communication

7

UART-RXD

Receive pin for UART communication

8

OUT1

External GPIO pin (user configurable)

9

RAD_INT_IN

GPIO pin for interrupt signals (user configurable)

10

OUT2

External GPIO pin (user configurable)

11

PWM_OUT2

External GPIO with CCU4 unit (user configurable)

12

PWM_OUT1

External GPIO with CCU4 unit (user configurable)

13

VCC_5V_EXT

External +5.0 V input power supply pin (maximum = 5.5 V)

14

GND

Ground

15

IF2I_LG

BGT24MTR12 RX-2 I-channel – analog signal output – first gain stage

16

IF2Q_LG

BGT24MTR12 RX-2 Q-channel – analog signal output – first gain stage

17

VCOARSE

BGT24MTR12 – VCO coarse tuning input (0.5 to 3.3 V)

18

VFINE

BGT24MTR12 – VCO fine tuning input (0.5 to 3.3 V)

19

PLL_MUX

Multiplexed input/output pins for ramp triggers, FSK/PSK modulation,
FastLock and diagnostics

20

PLL_MOD

Multiplexed input/output pins for ramp triggers, FSK/PSK modulation,
FastLock and diagnostics

21

IF1I_HG

BGT24MTR12 RX-1 I-channel – analog signal output – second gain
stage

22

IF1Q_HG

BGT24MTR12 RX-1 Q-channel – analog signal output – second gain
stage

23

IF2I_HG

BGT24MTR12 RX-2 I-channel – analog signal output – second gain
stage

24

IF2Q_HG

BGT24MTR12 RX-2 Q-channel – analog signal output – second gain
stage

25

BGT24_ANA

Multiplexed output pins of BGT24MTR12 to read various sensor values

26

IF1Q_LG

BGT24MTR12 RX-1 Q-channel – analog signal output – first gain stage

27

IF1I_LG

BGT24MTR12 RX-1 I-channel – analog signal output – first gain stage

28

GND

Ground

Application Note page 28 of 38 V1.3
2020-05-05

Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

The pin headers enhance the functionality of the module significantly. They allow probing the analog outputs
of the sensor module and also probing various other signals provided to the IC. In principle, the accessibility of
several pins on the radar IC and the IF signals available via the external pin headers enable interfacing the
module with an external signal processor. Apart from the onboard user LEDs, the external headers provide two
additional user-configurable GPIO pins from the microcontroller with a number of features, and can be used to
drive external shields such as the Infineon RGB LED lighting shield.

4.10 Microcontroller unit – XMC4700

The Position2Go platform uses an XMC4700 32-bit ARM® Cortex™-M4 MCU to perform the radar signal processing.
The XMC4700 takes care of communication with all the subsystems on the radar module, enables data
acquisition, performs the complete radar signal processing (including sampling and FFT) and communicates the
results via its UART or USB interface to an external device.

An XMC4700 in a 194-pin BGA package is used, featuring a 144 MHz CPU frequency, 2048 kB Flash and 352 kB RAM.
Four 12-bit ADCs help to implement the radar signal sampling and also acquire the various sensor data from the
BGT24MTR12 MMIC. The MCU has also a USB 2.0 device interface which enables communication with a PC
directly. Figure 20 shows a system block diagram of the XMC4000 series MCUs.

Please refer to [2] for detailed information on the XMC4700 microcontroller.

Figure 20 Block diagram – XMC4700

4.11 Onboard debugger and UART connection

The onboard breakable debugger supports two-pin SWD and UART communication. Both require the
installation of SEGGER’s J-Link driver (refer to STEP 6, in Figure 2) which is part of the DAVE™ installation (refer
to STEP 7 in Figure 3).

During installation of the J-Link driver make sure to select the option “Install USB Driver for J-Link-OB with

CDC” as shown in Figure 21.

Figure 21 Recommended installation options for the J-Link driver

Application Note page 29 of 38 V1.3
2020-05-05

Hardware description

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

Table 8 shows the pin assignment of the XMC4200-VQFN48 MCU used for debugging and UART connection.

Table 8 XMC4200 pins used for debugging and UART communication

Port pin

Pin function

TMS (Pin 35)

Data pin for debugging via SWD/SPD

TCK (Pin 39)

Clock pin for debugging via SWD

0.5

Transmit pin for UART communication

0.4

Receive pin for UART communication

The debugger section supports communication between a PC/laptop and target XMC™ device via a UART-to­USB bridge). Therefore, the UART pins of the target XMC4200 on the radar main board are connected to the
TX/RX pins of the debug connector. The TX pin of the debugger MCU is connected to the RX pin of the target
XMC4200 MCU. The RX pin of the debugger is connected to the TX pin of the XMC™ target device.

The connectors J6 (Cortex-10 pin) and J7 (5-pin header) shown in Figure 22 are used for internal development
and testing purposes and are not recommended for customer use.

Figure 22 Breakable onboard debugger section

4.12 User LEDs

Some pins of the XMC4700 on the Distance2Go module are connected to external LEDs on the antenna side of
the PCB for status indication. Table 9 lists the user LEDs pin assignment.

Table 9 User LEDs pin assignment

LED

MCU port pin

D8 (green LED)

P7.8 (H14)

Application Note page 30 of 38 V1.3
2020-05-05

Measurement results

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

5 Measurement results

5.1 Measurement default configuration

The Position2Go board was used in the default configuration for distance and angle measurements:

 BW: 200 MHz
 Chirp time: 300 μs
 TX power level: 7
 RX PGA level: L4
 RX BGT LNA gain: enabled
 Duty-cycle status: enabled

5.2 Maximum distance measurement

The maximum distance was measured with a defined detection range threshold of 100 LSB in an outdoor
scenario with minimum environmental clutter. Higher detection ranges can be achieved with larger RCS targets
and by increasing the RX PGA level.

Figure 23 Maximum distance vs. AoA

For indoor measurements, like with all FMCW radar, the maximum detection range of human targets will
reduce significantly. It is challenging to quantify the maximum detection range in such indoor measurement
cases reliably due to unknown levels of background clutter specific to each environment.

Application Note page 31 of 38 V1.3
2020-05-05

Measurement results

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

5.3 Range accuracy measurement

Figure 24 shows the set-up of the radar module for range measurements and the range accuracy plots for the
measurements.

As can be seen from the measurement plots, the target could be measured up to 18 m away with an accuracy of
±15 cm up to 13 m and accuracy of ±25 cm for the 13 to 18 m range.

Figure 24 Range accuracy for 1 m

2

corner reflector target

0

300

600

900

1200

1500

1800

0 300 600 900 1200 1500 1800

Measured Distance (cm)

Actual Distance (cm)

Actual Distance vs. Measured Distance

1m² RCS target

-40

-35

-30

-25

-20

-15

-10

-5

0

5

10

15

20

25

30

35

40

0 300 600 900 1200 1500 1800

Delta Distance (cm)

Actual Distance (cm)

Distance Accuracy

1m² RCS target

Application Note page 32 of 38 V1.3
2020-05-05

Measurement results

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

5.4 Angular accuracy measurement

Figure 25 shows the set-up of the radar module for range measurements and the angular accuracy plots for the
measurements. The demo board was used in the default configuration (as mentioned in Section 5.1). For
accurate angle measurements it is necessary to avoid signal clipping in the IF baseband section.

The measurement was performed in an outdoor environment at 3 m distance with an RCS target of 1 m². As can
be seen from the results, the angular accuracy was ±2 degrees in the ±20 degrees angular range and ±8
degrees in the ±65 degrees angular range.

Figure 25 Angular accuracy for 1 m

2

corner reflector target

-12

-10

-8

-6

-4

-2

0

2

4

6

8

10

12

-65

-60

-55

-50

-45

-40

-35

-30

-25

-20

-15

-10

-5

0

5

101520

253035404550556065

Delta Angle (

°)

Actual Angle (°)

Angle Accuracy at 3 m range

1m² RCS target

Application Note page 33 of 38 V1.3
2020-05-05

Measurement results

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

5.5 Temperature chamber measurement

Three temperature chamber measurements were performed for 25°C, 85°C and -35°C. Figure 26, Figure 27 and
Figure 28 show the results and verify that the Position2Go demo board remains within the designated ISM band
at these temperatures.

Figure 26 Temperature measurement at 25°C (markers at 24.000 GHz and 24.250 GHz)

Figure 27 Temperature measurement at 85°C (markers at 24.000 GHz and 24.250 GHz)

Figure 28 Temperature measurement at -35°C (markers at 24.000 GHz and 24.250 GHz)

Application Note page 34 of 38 V1.3
2020-05-05

Frequency band and regulations

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

6 Frequency band and regulations

6.1 24 GHz regulations

Infineon’s BGT24MTR12 radar sensor operates in the globally available 24 GHz bands. There is an industrial,
scientific and medical (ISM) band from 24 to 24.25 GHz. However, each country may have different regulations
in terms of occupied bandwidth, maximum allowed radiated power, conducted power, spurious emissions, etc.
Therefore, it is highly recommended to check the local regulations before designing an end product.

6.2 Regulations in Europe

In Europe, the European Telecommunications Standards Institute (ETSI) defines the regulations. For more

details on the ETSI standards, please refer to its document EN 300 440 V2.2.1. Please note that some countries

do not follow harmonized European standards. Thus, it is recommended to check national regulations for
operation within specific regions and monitor regulatory changes.

6.3 Regulations in the United States of America

In the USA, the Federal Communications Commission (FCC) defines standards and regulation. The ISM band
covers 24 to 24.25 GHz and one can operate a field-disturbance sensor anywhere within this band with allowed
power limits for certain applications. For details, please refer to FCC section number 15.245 or 15.249.

Application Note page 35 of 38 V1.3
2020-05-05

Authors

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

7 Authors

Radar Application Engineering Team, Business Line “Radio Frequency and Sensors”

Application Note page 36 of 38 V1.3
2020-05-05

References

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

8 References

[1] Infineon BGT24MTR12 – 24 GHz Radar IC – Datasheet
[2] Infineon XMC4700 32-bit ARM Cortex™-M4 Microcontroller – Datasheet
[3] Infineon Application Note – AN305 – “Users Guide to 24 GHz Radar Transceiver”
[4] 24 GHz industrial radar – FAQs
[5] Innosent Application Note – Application Note IV – “Recommendations for the using of radar sensors in

general and specifically for low cost devices”

[6] Innosent Application Note – Application Note II – “Detection and Ranging of moving and Stationary

Objects by using the FMCW radar principle”

[7] ETSI Regulations – EN 300 440 V2.2.1
[8] FCC Regulations – 15.245, 15.249

Application Note page 37 of 38 V1.3
2020-05-05

Revision history

Position2Go 24 GHz radar demo kit for ranging, movement and target position
estimation

Revision history

Document
version

Date of release

Description of changes

V1.0

2018-12-14

Initial version

V1.1

2019-06-14

p. 33: Added temperature chamber measurements
p. 35: Added frequency regulation information
Moved Firmware description, Programming API and GUI overview

sections to 24 GHz Radar Tools and Development Environment User
Manual

Moved Algorithm description section to P2G Software User Manual

V1.2

2019-09-16

p. 10: Added Minimum speed row to the System performance table

V1.3

2020-05-05

p. 10: Correction on minimum and maximum speed values and formula

Edition 2020-05-05

<AN_1812_PL32_1812_145434>

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