A Jointventure of
idw news
A | A | A

Measuring Distance and Speed with a thumbtack-sized Radar Sensor

The SUCCESS consortium has developed and implemented a fully integrated 122 GHz Radar sensor in 130nm SiGe-BiCMOS technology of IHP. The surface-mountable package has a size of 8 mm x 8 mm. It includes a mixed-signal Silicon Germanium (SiGe) chip and two antennas for transmitting and receiving. The prototype is a breakthrough towards a miniaturized, low-cost and high-resolution millimeter-wave sensor for distance and speed measurements.

Silicon technology has made tremendous progress towards ever higher device cut-off frequencies. Nowadays all RF components up to 120 GHz can be realized in silicon. Monolithic integration of the digital baseband processor, data converters, and mm-Wave circuitry on the same chip enables the fabrication of complete mm-wave sensor electronics at cost of well below 1 €. Furthermore mm-wavelengths radio waves result in mm-size antennas that can be integrated in the chip package. Hence complete miniaturized mm-Wave sensor systems can be realized using a System-in-Package approach.

The first prototype of an integrated sensor was implemented in July 2012. The sensor is based on a mixed signal chip fabricated in a 0.13 m SiGe BiCMOS technology from IHP. The homodyne transceiver includes a 120 GHz Voltage-Controlled-Oscillator, several amplifiers, an IQ-mixer and filters. Additional circuits are added that allow built-in-self-testing, such as power detectors and a frequency measurement unit. Parts of the transceiver are controlled digitally using an SPI interface. The chip is packaged in a ceramic housing using flip chip technology. The transmit and receive antennas are integrated into the package. Thus only DC and baseband signals need to be conducted to the package. The antennas are fabricated on a thin, flexible polyimide material. The metallic ground plane of the ceramic housing acts as a reflector for the antenna and causes the desired radiation direction upwards (perpendicular to the printed circuit board). The packaged sensor has a size of 8 mm x 8 mm and can be soldered onto a printed circuits board. A test board was fabricated to demonstrate the functionality of the packaged sensor. This allowed measuring a Doppler signal when detecting a moving object.

Low cost and miniaturization of mm-wave sensor systems will enable a great variety of distance sensing applications such as industrial sensing (distance, speed, material characterisation), public and private safety (motion detectors, even behind wall paper), automotive (wheel suspension measurement, pedestrian safety), replacement of cheap ultra-sonic sensors (distance measurement) and others.

The SUCCESS consortium consists of nine partners made up of research centres, universities and companies of six countries. The project has been financed by the 7th Framework Programme of the European Commission and has a budget of over 4.5 Million Euros for the next three years. The partners are the following ones: IHP, Robert Bosch GmbH, the Karlsruhe Institute of Technology and Silicon Radar GmbH from Germany, ST Microelectronics from France, SELMIC from Finland, Hightec MC AG from Switzerland, Evatronix from Poland, and the University of Toronto from Canada.

SUCCESS (Silicon-based Ultra Compact Cost-Efficient System Design for mmWave-Sensors)

More information:

Dr. Sun, Yaoming +49 335 5625 725 sun@ihp-microelectronics.com

Dr. Scheytt, Christoph ihp@ihp-microelectronics.com

idw :: 22.08.2012