Technical documentation Frequently asked questions for 24GHz industrial radar What is radar? Radar is an object-detection system that uses radio waves to determine the range, angle, or velocity of objects. A radar system consists of a transmitter producing electromagnetic waves in the radio or microwaves domain, an emitting antenna, a receiving antenna (separate or the same as the previous one) to capture any returns from objects in the path of the emitted signal, a receiver and processor to determine properties of the object(s). What product family is available? The BGT24M/L family is the largest and highest integrated 24GHz ISM band radar transceiver family currently in the market. It saves ~30 percent board space compared to discrete line ups. Infineon offers 4 different components, the BGT24MTR11 which combines one transmit and one receive channel, the BGT24MTR12 which comprises one transmit and two receive channels, and the BGT24MR2, a chip with 2 receive channels, combinable with both chipsets. Infineon recently released a new lower power, smaller form factor radar transceiver called BGT24LTR11 which comprises of one transmit and one receive channel. What applications can radar be used in? ››Drones-soft landing and collision avoidance ››Street lighting projects ››Intelligent door openers ››Home automation ››Speed meters ››Robotics ››Internet of things What are the radar processing technologies? Technique Complexity Movement Speed Doppler Low FSK Medium FMCW High Monopulse Medium Monopulse is an additional option for all the above operating modes www.infineon.com/24GHz Distance of moving objects Distance of static objects Angle of moving objects Technical Documentation What are some of the main features of the products available? ››Highest integration currently in the market ››Multiple combination Tx/Rx configurations available ››Fully packaged solution ››Low cost TSNP-16-9 package ››Distance detection up to 100 m ››Smallest packaged radar chip on the market What is radar transceiver? Radar transceiver (transmitter receiver) ››Transmits low energy radio frequency signal over Tx antenna (24 GHz, max. 100 mW) ››Receives reflected signal over Rx antenna ››Moving target generates low frequency Doppler output signal (so called IF) Tx Rx IF output FM input How does radar detect movement? Basic movement detector ››Output becomes active as soon as Doppler signals are present ››Implemented with discrete components or simple microcontroller Sensitivity Hold time t Amp Comparator Timer Output Technical Documentation What is the Doppler effect? Doppler effect Radar transceiver Low frequency Doppler signal Amplitude depends on reflectivity and distance. Frequency fd depends on object speed. Calculating the Doppler frequency fd = or v= 2 · fTx · v c0 · cos α (1) c0 · fd 2 · fTx · cos α (2) fd fTx c0 v α Doppler frequency Transmit frequency (24 GHz) Speed of light (3 · 108 m/s) Object speed in m/s Angle between beam and object moving direction α At a transmit frequency of f Tx = 24.125 GHz we get a Doppler frequency for a moving object at the IF output of fd = v [km/h] · 44 Hz · cos α or fd = v [m/s] · 161 Hz · cos α (4) How does Doppler processing calculate speed? Speed display ››Frequency (= speed) and direction are detected by complex FFT ››Implemented with FFT (Fast Fourier Transform) Sensitivity I Q ADC Direction + FFT YOUR SPEED ADC Microprocessor Speed [km/h] = fd / (44 Hz · cos α) Q I I and Q signals phase shifted by 90° depending on movement direction Technical Documentation How does radar measure distances? Typical measurement methods Distance measurement always needs bandwidth / modulated carrier Pulse radar ››Sends out a very short, powerful pulse ››Measures time of flight of reflected pulse ››Needs high bandwidth → not usable in K-band Continuous wave methods No pulse, but a continuous, frequency modulated carrier is sent ››FMCW: used to detect stationary and moving objects. A so called chirp is sent and mixed with the received signal. Low frequency output represents distance. ››FSK: used to get distances of moving objects. 2 frequencies are sequentially sent. 2 phase shifted Doppler signals represent distance. What is the difference between FMCW and FSK? FMCW and FSK Measuring distances need modulation of carrier → bandwidth Use Modulation FMCW (Frequency Modulation Continuous Wave) FSK (Frequency Shift Keying) For stationary and moving objects For moving objects only fp f f fa fb fM fb TM fRx Formula Resolution fTx R= c0 fb TM · · 2 fM 2 1 m, limited by K-band bandwidth 250 MHz Ta Tb t txa txb txa txb txa txb R= c0 · ∆φ 4π · (fa - fb) 1–100 cm, depending on signal processing t Technical Documentation What is current system availability? There are 3 demo boards available now. Please see below description and images. 2014 2015 2016 RFB2412 (BGT24TR12 + XMC4400) Sense2Go2 (BGT24MTR11 + XMC4200) Sense2GoL (BGT24LTR11 + XMC1300) 1) ››1 transmitter + 2 receivers ››Motion detection ››Doppler radar for speed monitoring ››Software based FMCW for distance ››Starter kit for radar and ››Starter kit for radar as well as IFX microcontroller development ››1 transmitter and 1 receiver ››Motion detection and Doppler radar for speed ››Low power mode for enhanced battery life ››Industrial standard interfaces via CAN and IOLINK ››Range to 15 m measurement of stationary objects - NEW ››Angle of arrival estimation - NEW microcontrollers ››Low end solution + development kit ››1 transmittet and 1 receiver ››Motion detection and Doppler radar for speed ››Low power mode for enhanced battery life ››Ultra small form factor 1) Now available RFB2412 BGT24MTR12 Transparent connector Sense2Go2 MCU disconnect and level shift XMC4400 MCU Sense2GoL with break away debugger Reverse current protection diode Micro-USB Voltage regulator User buttons and LEDs Pin header X2 Pin header X1 TVS diode User LED1 @ P1.5 User LED2 @ P1.15 BGT24MTR11 24 GHz radar IC USB OTG connector Baseband amplifiers Cortex® debug connector DC input 8 V … 36 V RF frontend Analog amplifiers RTC backup battery Crystal Power supply Is there a block diagram available for the Sense2GoL? +5 V +3.3 V Power supply (LDO) Switch +3.3 V +3.3 V VCC_BGT VCC_PTAT PTAT Balun V_PTAT Standby LED BGT24LTR11 MPA Balun +3.3 V Microcontroller IFI HPF ADC Amp2 Amp1 IFQ VCC_DIV DIV_OUT Frequency divider Balun ADC Polyphase filter LED2 FFT, DSP Balun 90° VTUNE Balun Optional res LED1 0° IFI LNA Balun IFQ R_TUNE PWM2 I/O Tx antenna Tx_ON PWM1 XMC1302 TxOUT RFIN Rx antenna Technical Documentation What are the key features of the Sense2GoL demo board? Features ››Capability to detect motion, speed and direction of movement (approaching or retreating) ››BGT24LTR11 – 24 GHz highly integrated low power RF MMIC ››XMC1302 ARM® Cortex®-M0 – 32-bit industrial microcontroller ››Integrated patch antennas ››Segger debugger break off board for reprogramming Kit contains ››User manual ››SW GUI to operate kit ››Precompiled C libraries provided ››PCB schematic and Gerber files Is this available as an MMIC or complete module? Infineon smart sensing solutions MMIC Features ››Radar-based motion detector operating in the 24 GHz ISM-band ››Long range distance detection of moving objects up to 30 m ››Wide range speed detection up to more than ±100 km/h Module suppliers using Infineon chip Technical benefits ››Large coverage areas such as warehouses, parking lots, ect. ››Robust against harsh conditions (rain, dust and temperature) ››Precise presence detection ››Fast measurement updates Customer benefits ››Excellent movement detection ››Fewer false alarms ››Energy savings ››Concealable ››Customized solution ››Off the shelf module from market partners Where do I go for additional information? www.infineon.com/24GHz Published by Infineon Technologies AG 81726 Munich, Germany © 2016 Infineon Technologies AG. All Rights Reserved. Please note! THIS DOCUMENT IS FOR INFORMATION PURPOSES ONLY AND ANY INFORMATION GIVEN HEREIN SHALL IN NO EVENT BE REGARDED AS A WARRANTY, GUARANTEE OR DESCRIPTION OF ANY FUNCTIONALITY, CONDITIONS AND/OR QUALITY OF OUR PRODUCTS OR ANY SUITABILITY FOR A PARTICULAR PURPOSE. WITH REGARD TO THE TECHNICAL SPECIFICATIONS OF OUR PRODUCTS, WE KINDLY ASK YOU TO REFER TO THE RELEVANT PRODUCT DATA SHEETS PROVIDED BY US. OUR CUSTOMERS AND THEIR TECHNICAL DEPARTMENTS ARE REQUIRED TO EVALUATE THE SUITABILITY OF OUR PRODUCTS FOR THE INTENDED APPLICATION. WE RESERVE THE RIGHT TO CHANGE THIS DOCUMENT AND/OR THE INFORMATION GIVEN HEREIN AT ANY TIME. Order Number: B132-I0384-V1-7600-EU-EC-P Date: 10 / 2016 Additional information For further information on technologies, our products, the application of our products, delivery terms and conditions and/or prices, please contact your nearest Infineon Technologies office (www.infineon.com). Warnings Due to technical requirements, our products may contain dangerous substances. For information on the types in question, please contact your nearest Infineon Technologies office. Except as otherwise explicitly approved by us in a written document signed by authorized representatives of Infineon Technologies, our products may not be used in any life- endangering applications, including but not limited to medical, nuclear, military, life-critical or any other applications where a failure of the product or any consequences of the use thereof can result in personal injury.