DEMOBGT60TR13CTOBO1

AN600 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Board version V2.2 About this document Scope and purpose This application note describes the function, circuitry, and performance of the BGT60TR13C shield, part of Infineon’s XENSIV™ 60 GHz radar system platform. The shield provides the supporting circuitry to the on-board BGT60TR13C monolithic microwave integrated circuit (MMIC) Infineon’s 60 GHz radar chipset with antenna-inpackage (AIP). The shield offers a digital interface for configuration and transfer of the acquired radar data to a microcontroller board, e.g., Radar Baseboard MCU7. Intended audience The intended audience for this document are design engineers, technicians, and developers of electronic systems, working with Infineon’s XENSIV™ 60 GHz radar sensors. Related documents Additional information can be found in the documentation provided with the Radar Development Kit tool in the Infineon Developer Center (IDC), or from www.infineon.com/60GHz. Application note www.infineon.com Please read the sections “Important notice” and “Warnings” at the end of this document Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform 60 GHz radar system platform Table of contents About this document ....................................................................................................................... 1 Table of contents ............................................................................................................................ 2 1 1.1 1.2 Introduction .......................................................................................................................... 3 60 GHz radar system platform ................................................................................................................ 3 Key features ............................................................................................................................................. 3 2 2.1 System specifications ............................................................................................................. 4 Typical current consumption ................................................................................................................. 4 3 3.1 3.2 3.3 3.4 3.5 3.6 Hardware description ............................................................................................................. 5 Overview .................................................................................................................................................. 5 BGT60TR13C MMIC .................................................................................................................................. 6 Sensor supply .......................................................................................................................................... 7 Oscillator.................................................................................................................................................. 8 Connectors .............................................................................................................................................. 8 EEPROM ................................................................................................................................................. 10 4 Firmware .............................................................................................................................11 5 5.1 5.2 Measurement results .............................................................................................................12 Radiation pattern .................................................................................................................................. 12 Phase noise measurements .................................................................................................................. 14 6 6.1 6.2 Frequency band and regulations .............................................................................................16 Regulations in Europe ........................................................................................................................... 16 Regulations in the United States of America........................................................................................ 16 References ....................................................................................................................................17 Revision history.............................................................................................................................18 Disclaimer.....................................................................................................................................19 Application note 2 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Introduction 1 Introduction 1.1 60 GHz radar system platform The 60 GHz radar system platform is the demo platform for Infineon’s 60 GHz radar solutions. It consists of the Radar Baseboard MCU7 as the microcontroller board and a radar sensor board, like the BGT60TR13C shield for Infineon’s 60 GHz radar sensor chip. This application note focuses on the BGT60TR13C shield. Detailed information about the Radar Baseboard MCU7 can be found in the corresponding application note [1]. Figure 1 illustrates the Radar Baseboard MCU7 with the BGT60TR13C shield. Both boards have markers. These markers must be aligned to correctly plug in a sensor board. a) Radar Baseboard MCU7 Markers Sensor board b) Figure 1 Radar Baseboard MCU7 with the BGT60TR13C shield (a) unplugged or (b) plugged in 1.2 Key features The BGT60TR13C shield is optimized for fast prototyping designs and system integrations as well as initial product feature evaluations. The board offers developers the flexibility to choose their own platform depending on their preferred use cases. The sensor supports various use cases, serving a broad application spectrum such as presence detection, proximity sensing, people counting and tracking, gesture sensing and material classification. These use cases target applications such as smartphones, notebooks, TVs, smart speakers, wearables, smart home and building automation systems for comfort, energy savings and security/safety functions. Presence detection may only require 1 mW of power in the sensor under certain circumstances. Some key features of the BGT60TR13C shield are as follows: • Minimized form factor of 17 x 12.7 mm² RF board with Antenna-in-Package (AIP) of 6.5 x 5.0 x 0.85 mm³ • Flexible platform selection • Variable connector options, and option to solder onto other PCBs • Highly flexible configuration on FMCW modulation • Power consumption can be optimized according to use case Application note 3 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform System specifications 2 System specifications 2.1 Typical current consumption The typical current consumption of the whole 60 GHz radar sensor platform, consisting of a Radar Baseboard MCU7 and a BGT60TR13C shield, can be found in Table 1. When the MCU is in reset, the power consumption stays below 10 mW. Without a sensor, approximately 150 mW are consumed, and with a BGT60TR13C shield, the power consumption can be as high as 1.5 W in continuous wave (CW) operation. The BGT60TR13C radar sensor’s share of the total power can reach up to 350 or 400 mW in CW operation. However, the exact value will depend on the operating condition of the radar sensor. As the sensor is typically operated in duty-cycle mode, the actual power consumption figures tend to be much lower. In the design of the radar sensor, the developers take care to optimize power saving in duty-cycle operation. For this reason, most use cases will consume less than 100 mW. Table 1 Typical current consumption of the 60 GHz radar sensor platform with the BGT60TR13C shield Condition Current consumption Power consumption Power consumption BGT60TR13C shield MCU in reset ~ 2 mA ~ 10 mW – No sensor attached ~ 29 mA ~ 150 mW – Sensor attached but deactivated ~ 110 mA ~ 550 mW – BGT60TR13C shield attached and in CW operation (maximum power consumption) 290 to 300 mA ~ 1.5 W ~ 350 mW Application note 4 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Hardware description 3 Hardware description This section presents a detailed overview of the BGT60TR13C shield’s hardware building blocks, such as BGT60TR13C MMIC, power supply, crystal, and board interfaces. 3.1 Overview Top side b) Bottom side 12.7 mm a) 17 mm Figure 2 The BGT60TR13C shield The dimensions of the BGT60TR13C shield printed circuit board (PCB) are 17 mm x 12.7 mm. Mounted on top of the PCB is a BGT60TR13C, Infineon’s 60 GHz radar sensor with integrated antennas. Because the antennas are integrated into the BGT60TR13C chip package, the PCB can be manufactured using a standard FR4 laminate. No special high-frequency (HF) materials are required to build a BGT60TR13C system. The radar sensor is the central element on the top side of the PCB (U1 in Figure 2a). The bottom side of the PCB features the main interfaces to the Radar Baseboard MCU7 [1] (P3 and P4 in Figure 2b). The castellated holes on the edges of the PCB (P1 and P2 in Figure 2a) provide additional access to the most important signals of the BGT60TR13C. By using these side connectors and removing P3 and P4, the BGT60TR13C shield can be soldered onto other PCBs as a radar module. Vdigital 1.8VSensor 3.3Vdigital EEPROM I2C 2 3.3Vdigital LED RST IRQ 14 OpenDrainLED 3.3VSensor 1.8VSensor 1.8VSensor 1.8VSensor 1.8VSensor 1.8VSensor Low pass filter Low pass filter Low pass filter Low pass filter Low pass filter Application note VDD,LF VDD,A VDD,D VDD,PLL VDD,RF Low pass filter VDD,OSC Figure 3 4 BGT60TR13C SPI Sensor interface Castellated holes conn. 80MHz quartz 80MHz Block diagram of the BGT60TR13C shield 5 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Hardware description The block diagram in Figure 3 depicts the concept behind the board. Each of the signals on the castellated holes’ side connectors corresponds with a signal on the sensor connector. To provide the correct level shifter voltage for the MCU board, the 1.8 Vsensor supply line is connected with Vdigital (see section 2.3 of reference [1]). When the shield is plugged into the Radar Baseboard MCU7, the sensor’s supplies are initially deactivated. Only the EEPROM is powered. The MCU will read the content of the EEPROM’s memory to determine which sensor is plugged into the sensor interface. Only when the board has been correctly identified are the sensor’s supplies activated. Radar sensors are extremely sensitive to noise and crosstalk on the supply domains. Therefore, the different supply domains must be decoupled. On the BGT60TR13C shield, this is realized by a pi-shaped low-pass filter on each supply domain (and the oscillator supply). Communication with the radar sensor is mainly performed via a serial peripheral interface (SPI) bus. Additionally, two more digital lines are required for operation. One line signals the MCU when new data needs to be fetched. The other allows the MCU to perform a hardware reset of the sensor. Furthermore, an MCU-controllable LED is mounted on the board. This allows the MCU to signal for example if the sensor is activated or deactivated. 3.2 BGT60TR13C MMIC Infineon’s 60 GHz radar sensor with AIP, the BGT60TR13C, serves as the main element on the BGT60TR13C shield. Integrated into the package chip contains one transmit antenna and three receive antennas. Its dimensions are 6.5 mm ± 0.1 mm x 5.0 mm ± 0.1 mm, as illustrated by the package outline in Figure 4a and in more detail in Figure 5a and Figure 5b. Its height is 0.85 mm ± 0.05 mm. When oriented as in the figure, the radar sensor will emit vertical polarization. Thus, the E-plane is vertical, and the H-plane is horizontal. The freespace wavelength of 60 GHz, denoted by lambda, is about 5 mm. The horizontal spacing between receive antenna 1 (Rx1) and receive antenna 3 (Rx3) as well as the vertical spacing between receive antenna 2 (Rx2) and Rx3 is lambda over 2. This enables angular measurements perpendicular to the chips’ surface providing a horizontal range of ±90 degrees using Rx1 and Rx3 and a vertical range of ±90 degrees using Rx2 and Rx3 respectively. 1 SPI_CLK GND GND SPI_MISO IRQ VSSRF DI VSSRF DO VSSRF GND RST SPI_CSN VSSRF VSSRF VSSRF VSSRF CLK VSSRF VSSRF VSSRF VSSRF VSSRF VSSRF VSSRF VSSD VSSD C1 C9 D1 D9 E1 E9 BGT60TR13C RST VDDRF CSN VDDRF VDDD VSSRF VDDA VSSRF VSSA VSSRF VAREF VSSRF VDDRF OSC_CLK SPI_MOSI F1 F9 G1 G9 H1 H9 J1 J9 K1 K9 L1 L9 M1 M2 IRQ VDD_RF GND VDD_D VDD_A Figure 4 U1 VSSRF VSSRF VDDVCO DIV_TEST VDDPLL VDDLF TP1 GND M9 M7 M6 M5 M4 M3 DIVOUT b) B9 B8 B4 B3 B1 A9 A8 A7 A6 A5 A4 A3 A2 A1 a) VDD_VCO VDD_PLL VDD_LF OSC_80M C3 470nF GND Package outline (a) and schematics (b) of the BGT60TR13C The BGT60TR13C has five 1.8 V power domains: analog, digital, radio frequency (RF), phase-locked loop (PLL) and the voltage-controlled oscillator (VCO) circuitry. Additionally, there is a 3.3 V domain for the loop filter (LF) – see Figure 4b for details. When the chip is operated with a LF supply voltage below 3.3 V, the maximum VCO frequency and thus the sensor’s bandwidth will be restricted accordingly. The signal strength will, of course, decrease with increasing angle – see section 5.1 for details. Application note 6 1 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Hardware description To reduce the system phase noise and frequency jitter, it is recommended to short the ground contacts of the different power domains. Therefore, it is essential to have a solid ground plane right underneath the chip with no signal lines. The suggested pad layout is shown in Figure 5c. The BGT60TR13C provides the following digital signal lines: oscillator input, four SPI signals, hardware reset line and interrupt request output (to the MCU). Furthermore, there is a divider output signal. It must be enabled in the chip and outputs a 1:16 fraction of the RF generated by the radar sensor. This can be used to measure the phase noise of the sensor – see section 5.2 for details. b) 5.0 ± 0.1 2 1 4 3 6 5 Top view c) 5.0 ± 0.1 0.24 ± 0.03 8 7 Side view 9 1 B C 9 Ø0 .2 7 6.5 ± 0.1 Ø0.3 ± 0.05 G H G H J 0.33 J E F 0.33 E F L 8 7 5 C D K 6 5 B D 6.5 ± 0.1 4 3 A 0.5 A 2 0.5 Top view a) K L M M 0.33 0.5 0.858 ± 0.05 0.33 0.5 Figure 5 Top (a) and side view (b) of the package and the suggested pad layout of BGT60TR13C (c) – all dimensions in mm 3.3 Sensor supply Since radar sensors are sensitive to supply voltage fluctuations or crosstalk between different supply domains, a low-noise power supply as well as properly decoupled supply rails are vital. The Radar Baseboard MCU7 provides a low-noise supply (see section 2.2 of reference [1]). Figure 6 depicts the schematics of the pi-shaped low-pass filters employed to decouple the supplies of the different power rails in the chip. High attenuation of voltage fluctuations in the MHz regime is provided by ferrite beads. For example, the SPI, which runs at up to 50 MHz, induces voltage fluctuations on the digital domain, which would then transfer into the analog domain if not for the decoupling filters. The ferrite beads are chosen such that they can handle the maximum current of the sensor of about 200 mA with a low DC resistance (below 0.25 Ω) and an inductance as high as possible. The high inductance will reduce the cut-off frequency of the low-pass filter, which provides better decoupling for lower frequencies. 3V3Sensor C4 10µF L2 Ferrite Bead GND 1V8Sensor C11 10µF VDD_LF L4 C5 1µF GND VDD_D 1V8Sensor Figure 6 Application note C12 1µF GND VDD_RF L3 C6 Ferrite Bead 10µF GND Ferrite Bead GND 1V8Sensor C7 10µF C8 1µF C9 1µF C10 1µF GND L5 VDD_A C13 Ferrite Bead 100nF GND 1V8Sensor C14 10µF GND L6 VDD_PLL Ferrite Bead C15 1µF GND 1V8Sensor L7 VDD_VCO Ferrite Bead C16 1µF GND Schematics of the low-pass filters 7 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Hardware description 3.4 Oscillator Infineon’s XENSIV™ BGT60TR13C radar sensor requires an oscillator source with a stable reference clock providing low phase jitter and low phase noise. Therefore, the BGT60TR13C shield employs a Kyocera KC2016 quartz oscillator, which is supplied with 1.8 V as depicted in Figure 7. This oscillator source will output a stable 1.8 V digital signal. The most important parameters for choosing an oscillator are phase jitter and phase noise. Other oscillators should have similar phase jitter and phase noise as the Kyocera KC2016. Furthermore, the radar sensor will work most efficiently if the reference oscillator signal is neither too strong nor too weak. The series resistor R1 reduces the RF level at the sensor so that it is at the ideal range for the BGT60TR13C. If a redesign of the board contains a different signal source or a vastly different layout is designed, the value of R1 (150 Ω) may have to be adjusted. A higher resistance results in a lower signal at the radar sensor. If the signal level is too low, the phase noise of the sensor will deteriorate – see section 5.2 for details of phase noise measurement. With a low resistance, the signal level at the sensor will be high, and in the Range-Doppler illustration of the radar data, a peak (or ghost target) will appear for low distances. X1 VDD_OSC INHx VCC GND OUT L1 C1 10nF 1V8Sensor Ferrite Bead C2 1µF KC 2016 80MHz R1 Figure 7 OSC_80M 150Ω The oscillator circuit on the BGT60TR13C shield For this reason, the phase noise needs to be measured as well as the radar data needing to be illustrated with a Range-Doppler plot to optimize the series resistance of the layout. The series resistance must be varied by soldering different resistors into the circuit. An optimized series resistance will show ideal phase noise behavior of the sensor paired with a clean Range-Doppler plot. If the phase noise behavior is non-ideal, the resistance value must be lower. If a peak appears in the Range-Doppler plot, the resistance must be higher. 3.5 Connectors The BGT60TR13C shield is an extension board of Infineon’s 60 GHz radar system platform without a microcontroller. The shield must be connected to an MCU board, like the Radar Baseboard MCU7 [1]. The BGT60TR13C shield contains two different types of connectors to interact with an MCU board, as depicted in Figure 8a. Visible on the top and bottom side of the PCB are the castellated holes. The contacts on this connector give access to all signals required for operation of the BGT60TR13C. The pin-out of the connectors can be seen in Figure 8b as well as on the silkscreen on the bottom side of the PCB (Figure 8a). The main connector interface of the BGT60TR13C shield contains two Hirose DF40C-20DP-0.4V connectors. On the MCU side, the Radar Baseboard MCU7 contains the corresponding DF40C-20DS-0.4V connectors. Figure 9 illustrates the pin-out and the pad layout of the Hirose connectors of the BGT60TR13C shield. To provide the information of the correct digital signal level to the host board, the line Vdigital is shorted with the 1.8 V supply. On the top side of the shield is a marker that must be aligned with the marker on the MCU board for correct shield alignment, as depicted in Figure 1. There is a risk of the Hirose connectors wearing out when regularly plugged into and unplugged from the shield. To prevent this, do not lift the board on the short side out of the connector, as illustrated in Figure 10a. Application note 8 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Hardware description Instead, simply pull on the long side of the board, thereby tilting the short side, as shown in Figure 10b. This will significantly increase the lifetime of the connectors. a) b) Castellated holes Sensor connectors Bottom side P1 OpenDrain_LED 1 RST 2 SPI_CSN 3 SPI_MISO 4 SPI_MOSI 5 SPI_CLK 6 IRQ 7 Castellated Holes P2 1 2 3 3V3digital 4 5 GND 1V8Sensor 6 3V3Sensor 7 GND I2C_SDA I2C_SCL Castellated Holes Figure 8 Connectors on the bottom side of the BGT60TR13C shield (a) and the pin-out of the castellated hole connectors (b) a) GND 3V3digital I2C_SDA GND 1V5Sensor 1V5Sensor 1V8Sensor 1V8Sensor 1V8Sensor 3V3Sensor 3V3Sensor GND MP1 P3 MP2 1 3 5 7 9 11 13 15 17 19 2 4 6 8 10 12 14 16 18 20 MP3 MP4 GND GND I2C_SCL IRQ SPI_CLK SPI_MOSI SPI_MISO SPI_DIO2 RST SPI_CSN OpenDrain_LED DACin ADCout2 ADCout1 GPIO GND 1V8Sensor OpenDrain4 OpenDrain3 OpenDrain1 GND GND GND DF40C-20DP-0.4V(51) MP1 1 3 5 7 9 11 13 15 17 19 MP3 P4 MP2 2 4 6 8 10 12 14 16 18 20 GND OpenDrain2 GND 3V3digital MP4 GND DF40C-20DP-0.4V(51) b) GND 3V3digital I2C_SDA GND 1V5Sensor 1V5Sensor 1V8Sensor 1V8Sensor 1V8Sensor 3V3Sensor 3V3Sensor GND GND GND I2C_SCL BGT_IRQ SPI_CLK SPI_MOSI SPI_MISO GPIO1 BGT_RST SPI_CSN GND OpenDrain_LED DAC GND ADC2 ADC1 GPIO2 1V8Sensor OpenDrain4 OpenDrain3 OpenDrain1 GND GND GND GND OpenDrain2 3V3digital GND 12mm Figure 9 Application note Pinout (a) and pad layout (b) of the sensor connectors on the BGT60TR13C shield 9 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Hardware description a) b) Figure 10 How to unplug the sensor-to-sensor connectors of the Radar Baseboard MCU7 3.6 EEPROM The BGT60TR13C shield contains an EEPROM (24CW128X) connected via an I2C interface to store data like a board identifier. Its schematics can be seen in Figure 11. This EEPROM contains a descriptor indicating the type of the shield board and MMIC. This is used by the firmware to communicate properly with the shield. 3V3digital I2C_SCL R2 2.2kΩ Figure 11 Application note U2 VDD VSS SCL SDA 24CW128X 3V3digital GND I2C_SDA R3 2.2kΩ Schematics of the EEPROM 10 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Firmware 4 Firmware The Radar Baseboard MCU7 comes with a default firmware which is intended to serve as a bridge between a host (typically a PC) and the BGT60TR13C RF shield, which is mounted on the sensor connectors. When the firmware detects a BGT60TR13C shield, it automatically configures the driver layer for the BGT60TR13C sensor. This includes configuring the chip as well as setting up the MCU to initiate a serial peripheral interface (SPI) transfer when the BGT signals the availability of new data via the IRQ line. The firmware will also configure the communication layer so that radar and BGT60TR13C specific messages are understood. For more details, please refer to the AN599 - Radar Baseboard MCU7 application note. Application note 11 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Measurement results 5 Measurement results 5.1 Radiation pattern The datasheet of the BGT60TR13C only shows the 3-dB values for transmit and receive antenna characteristics. This subsection shows the radiation pattern of a typical BGT60TR13C radar sensor. Figure 12a and Figure 12c show the equivalent isotropically radiated power (EIRP) of the transmit antenna in E-plane and H-plane at a frequency of 60.5 GHz. Figure 12b and Figure 12d illustrate the antenna characteristics of the three receive antennas in E-plane and H-plane at a frequency of 60.5 GHz. TX - E-plane at f = 60.5 GHz a) -30° -15° 0° 15° 30° -45° -30° 45° -60° -25 -20 -15 -10 -5 0 5 Normalized Antenna Gain (dB) -30° -45° -60° -75° -90° Figure 12 0° 15° 15° 90° 30° 45° 60° 75° -90° -25 -20 -15 -10 -5 0 5 Normalized Antenna Gain (dB) RX - H-plane at f = 60.5 GHz d) 30° -30° 45° -45° 60° -60° 75° -25 -20 -15 -10 -5 0 5 Normalized Antenna Gain (dB) RX 1 RX 2 RX 3 -75° TX - H-plane at f = 60.5 GHz -15° 0° -60° 75° -90° -15° -45° 60° -75° c) RX - E-plane at f = 60.5 GHz b) -75° 90° -90° -15° 0° 15° 90° RX 1 RX 2 RX 3 30° 45° 60° 75° -25 -20 -15 -10 -5 0 5 Normalized Antenna Gain (dB) 90° Radiation Pattern of a typical BGT60TR13C To analyze the radar radiation pattern, the BGT60TR13C shield is characterized along the E-plane and H-plane of the sensor. A corner reflector is placed opposite the radar board. The radiation emitted by the radar sensor is reflected by the corner reflector and measured with the receiver antennas of the radar board. In order to avoid clutter, the measurement is typically performed in an anechoic RF chamber. The measurement characterizes the chip in radar operation. Thus, both transmit and receive antennas are part of the measurement. For the measurement, the standard FMCW radar scheme is followed and the signal at all three receive antennas is recorded. Then the sensor is rotated into different angles and the measurement is repeated for each angle, resulting in an angle dependence of the received signals for all three receiver antennas. Figure 13a shows the measurement set-up that is used. The corner reflector is placed at a distance of 0.4 m from the BGT60TR13C shield in an anechoic chamber. The board is rotated by ±90 degrees along the E-plane (Figure 13b) and H-plane (Figure 13c). The results for the E-plane can be seen in Figure 14a and the ones for the H-plane in Figure 14b. Thereby, a typical board was measured with a frequency chirp from 60.5 to 61.5 GHz and the results of all three receive antennas are plotted. In the E-plane, a side lobe is visible, and the main lobe is not perpendicular to the chip surface but rotated by about 25 degrees. This effect is due to the close proximity of the antennas in the package, and it is stronger for electric fields than for magnetic fields. In the H-plane, no side lobes are visible, and the main lobe is perpendicular to the chip surface. Figure 14c shows the dependence of the received signal strength on the used center frequency of the chirp for the direction 0° in E-plane and 0° in Application note 12 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Measurement results H-plane. The strongest signal can be received at around 59.5 GHz, and it decreases towards the edges of the band. a) Anechoic RF chamber 0.4 m Corner reflector E-plane b) Radar board Axis of rotation c) H-plane Axis of rotation -90° -90° Figure 13 +90° +90° Set-up for radiation pattern measurement E -Plane (fchirp = 60.5 - 61.5 GHz) a) -30° -30° 60° 60° Rx 1 Rx 2 Rx 3 90° -90° -30 -25 -20 -15 -10 -5 0 Normalized Received Power (dB) Normalized Received Power (dB) c) 30° -60° Rx 1 Rx 2 Rx 3 -90° 90° -30 -25 -20 -15 -10 -5 0 Normalized Received Power (dB) 0 Rx 1 - 0° E-Plane, 0° H-Plane Rx 2 - 0° E-Plane, 0° H-Plane Rx 3 - 0° E-Plane, 0° H-Plane -1 -2 -3 -4 -5 -6 58.5 Application note 0° 30° -60° Figure 14 H-Plane (fchirp = 60.5 - 61.5 GHz) b) 0° 59 59.5 60 60.5 61 fcenter (GHz) 61.5 62 62.5 63 Radiation pattern measurements of a typical sample for a chirp from 60.5 to 61.5 GHz of Eplane (a) and H-plane (b) as well as the received power in dependence of the frequency (c) 13 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Measurement results 5.2 Phase noise measurements The phase noise is a way to characterize the RF signal. Thereby, the signal with an offset from the carrier signal is put in relation with the carrier itself. In radar data processing with BGT60TR13C, the typical IF frequencies are in a range from about 10 kHz to 1 MHz. Therefore, the phase noise must be investigated within this range as well. The phase noise can be measured directly at the radar frequency, as illustrated in Figure 15a. A horn antenna placed in front of the sensor receives the radiation emitted by the BGT60TR13C. Then, via a waveguide, the RF signal is transferred to a harmonic mixer, which in combination with a signal analyzer enables measurement of the RF signal emitted by the radar sensor. A typical set-up for this measurement could consist of: • Keysight Signal Analyzer PXA N9030A (with phase noise measurement software) • Keysight M1970V waveguide harmonic mixer • Dorado International GH-15-20 horn antenna The BGT60TR13C also has the option to emit the 1:16 divided RF signal at the DIV_TEST pin, shown in Figure 4b. The access to the divided RF signals provides another way to characterize the phase noise of the radar sensor. For measurement, the user must solder a coaxial cable to test point 1 and a GND pad of the BGT60TR13C, depicted in Figure 15b. This coaxial cable can then be connected to a signal analyzer like the Keysight N9030A and the phase noise can be measured with phase noise measurement software. a) Signal analyzer Harmonic Waveguide mixer Horn antenna b) Test point 1 Pads with GND potential Figure 15 Phase Noise (dBc / Hz) a) -70 Measurement set-ups for phase noise measurement. Direct RF measurement with a harmonic mixer (a) and with a divided signal at test point 1 (b). fCW = 58 GHz b) -70 fCW = 60 GHz c) -70 -75 -75 -75 -80 -80 -80 -85 -85 -85 -90 10 Figure 16 Application note 100 f (kHz) 1000 -90 10 100 f (kHz) 1000 -90 10 fCW = 63.5 GHz 100 f (kHz) 1000 Phase noise measurements of a typical device with three test frequencies (58 GHz, 60 GHz, 63 GHz) 14 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Measurement results Figure 16 shows the phase noise measurement of a typical BGT60TR13C shield over three frequencies (58 GHz, 60 GHz, 63.5 GHz). The measurement was performed directly at the RF signal with a harmonic mixer. The phase noise is clean for all tested frequencies. To characterize possible differences between sensor interface 1 and sensor interface 2 of the Radar Baseboard MCU7, the phase noise of the board was measured at both sensor interfaces with a direct RF measurement and a harmonic mixer. The results are depicted in Figure 17 and they show that there is no difference between the different sensor interfaces for different sensor frequencies. Phase Noise (dBc / Hz) a) fCW = 58 GHz -70 b) -70 fCW = 60 GHz c) -70 -75 -75 -75 -80 -80 -80 -85 -85 -85 -90 10 Sensor Interface 1 Sensor Interface 2 Figure 17 Application note 100 f (kHz) 1000 -90 10 Sensor Interface 1 Sensor Interface 2 100 f (kHz) 1000 -90 10 fCW = 63.5 GHz Sensor Interface 1 Sensor Interface 2 100 f (kHz) 1000 Phase noise measurements of a typical board on sensor interface 1 and sensor interface 2 with three test frequencies (58 GHz, 60 GHz, 63 GHz) 15 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Frequency band and regulations 6 Frequency band and regulations Infineon’s XENSIV™ BGT60TR13C radar sensor operates in the globally available 60 GHz bands. Typically, there is a wide band (WB) from 57 to 64 GHz and within it, there is an industrial, scientific, and medical (ISM) band from 61.0 to 61.5 GHz. However, each country may have differing regulations in term of occupied bandwidth, maximum allowed radiated power, conducted power, spurious emissions, etc. Therefore, it is strongly recommended to check the local regulations before designing an end product. 6.1 Regulations in Europe In Europe, the European Telecommunications Standards Institute (ETSI) [3] defines the regulations. They allow operation of non-specific short-range devices within the 57 to 64 GHz WB with certain limitations. For more details on the ETSI standards, please refer to document EN 305 550 [5] as well as the Electronic Communications Committee’s recommendations [2]. Note that some countries do not follow harmonized European standards. For this reason, it is recommended to check national regulations for operation within specific regions and monitor regulatory changes. 6.2 Regulations in the United States of America In the USA, the Federal Communications Commission (FCC) [4] defines standards and regulation. The unlicensed WB covers 57 to 64 GHz, and you can operate a field disturbance sensor anywhere within this band within allowed power limits for certain applications. For details, refer to FCC section number 15.255 [6]. Application note 16 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform References References [1] Infineon Technologies AG. AN599: Radar Baseboard MCU7 [2] Committee, E. C. (n.d.). ERC Recommendation. Retrieved 03 12, 2019, from https://www.ecodocdb.dk/download/25c41779-cd6e/Rec7003.pdf [3] European Telecommunications Standards Institute. (n.d.). Retrieved 03 12, 2019, from https://www.etsi.org/ [4] Federal Communications Commission. (n.d.). Retrieved 03 12, 2019, from https://www.fcc.gov/ [5] Institute, E. T. (n.d.). EN 305 500. Retrieved 03 12, 2019, from https://www.etsi.org/deliver/etsi_en/305500_305599/305550/02.01.00_20/en_305550v020100a.pdf [6] Regulations, E. C. (n.d.). §15.255. Retrieved 03 12, 2019, from https://www.ecfr.gov/cgi-bin/textidx?SID=a484297320706bbafb187c022e7b3c0c&mc=true&node=se47.1.15_1255&rgn=div8 Application note 17 Revision 2.40 2023-02-14 BGT60TR13C shield XENSIV™ 60 GHz radar system platform Revision history Revision history Document revision Date Description of changes 1.00 2019-04-01 Initial version 2.00 2019-07-01 Added Vdigital for level shifter supply of the host board 2.10 2019-10-21 Fixed Typos in section 2.1 Changed schematics (symbol) in Figure 9 Added section 5.1 for antenna radiation pattern Changed figures 17 and 18 with the correspond text in section 5.2 2.20 2021-11-15 Updated BGT60TR13C shield to version 2.2 2.30 2022-11-07 Fixed Typos Removed Applications and use cases section. Updated References section 2.40 2023-02-14 Miscellaneous document cleanup updates Application note 18 Revision 2.40 2023-02-14 Disclaim er Trademarks All referenced product or service names and trademarks are the property of their respective owners. Edition 2023-02-14 Published by Infineon Technologies AG 81726 Munich, Germany © 2023 Infineon Technologies AG. All Rights Reserved. Do you have a question about this document? Email: erratum@infineon.com Document reference AN_1907_PL32_1907_091722 Important notice The information contained in this application note is given as a hint for the implementation of the product only and shall in no event be regarded as a description or warranty of a certain functionality, condition or quality of the product. Before implementation of the product, the recipient of this application note must verify any function and other technical information given herein in the real application. 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