Andreas Trasser

IR-UWB Radar Demonstrator for Ultra-Fine Movement Detection and Vital-Sign Monitoring

In this paper an impulse-radio ultra-wideband (IR-UWB) hardware demonstrator is presented, which can be used as a radar sensor for highly precise object tracking and breath-rate sensing. The hardware consists of an impulse generator integrated circuit (IC) in the transmitter and a correlator IC with an integrating baseband circuit as correlation receiver. The radiated impulse is close to a fifth Gaussian derivative impulse with σ = 51 ps, efficiently using the Federal Communications Commission indoor mask. A detailed evaluation of the hardware is given. For the tracking, an impulse train is radiated by the transmitter, and the reflections of objects in front of the sensor are collected by the receiver. With the reflected signals, a continuous hardware correlation is computed by a sweeping impulse correlation. The correlation is applied to avoid sampling of the RF impulse with picosecond precision. To localize objects precisely in front of the sensor, three impulse tracking methods are compared: Tracking of the maximum impulse peak, tracking of the impulse slope, and a slope-to-slope tracking of the objects reflection and the signal of the static direct coupling between transmit and receive antenna; the slope-to-slope tracking showing the best performance. The precision of the sensor is shown by a measurement with a metal plate of 1-mm sinusoidal deviation, which is clearly resolved. Further measurements verify the use of the demonstrated principle as a breathing sensor. The breathing signals of male humans and a seven-week-old infant are presented, qualifying the IR-UWB radar principle as a useful tool for breath-rate determination.

FCC compliant 3.1-10.6 GHz UWB Pulse Radar System using Correlation Detection

A short range 3.1-10.6 GHz single band ultra-wideband (UWB) pulse radar system is presented. The transmitter consists of a pulse generator that is connected to a broadband monopole antenna. The generated pulse shape is similar to the fifth derivative of the Gaussian bell shape and makes efficient use of the allocated FCC UWB frequency mask. The receiver is realized with a single-ended low noise amplifier and active single-ended to differential converters that drive the input ports of an analog correlator which uses pulse sequences as template signals. Measurements show a resolution capability of the radar system in the millimeter range. All active circuits have been realized in a low cost 0.8 mum SiGe HBT technology.

A single-chip 24 GHz receiver front-end using a commercially available SiGe HBT foundry process

The authors have demonstrated a fully integrated receiver frontend addressing the ISM-Band at 24 GHz utilizing a standard SiGe HBT MMIC process with a relaxed emitter scaling of 1.2 /spl mu/m, for the first time. Extremely compact circuit design and layout techniques are applied to a mature Si/SiGe technology, resulting in a low-cost integrated circuit enabling consumer-oriented systems at Ka band. The integrated components are a preamplifier, a mixer with an IF buffer and a local oscillator. The conversion gain is determined to be 16.3 dB for an intermediate frequency of 100 MHz.

Wafer level integration of a 24 GHz differential SiGe-MMIC oscillator with a patch antenna using BCB as a dielectric layer

This paper describes the wafer level integration of a differential 24GHz SiGe-MMIC oscillator including a buffer amplifier with a differentially driven patch antenna. The patch antenna is realized on 30¿m BCB (Benzo Cyclo Butene) used as a dielectric layer. The radiated power of the patch antenna driven by the oscillator is calculated based on measurements and the result is discussed.

Highly compact impulse UWB transmitter for high-resolution movement detection

In this paper the hybrid integration of an FCC-compliant fifth-order Gaussian derivative impulse generator IC together with a compact ultra-wideband Vivaldi antenna is presented. The setup results in a compact FCC-compliant impulse UWB transmitter. Measurements of the impulse shape in time and spectral domain are shown. With this transmitter a movement detection and the precise measurement of the movement deviation value by a correlation measurement technique is presented. This shows the ability of the UWB radar system to operate as a movement detection sensor. The measurements include a breath rate measurement of a human being.

Low-loss, low-cost, IC-to-board bondwire interconnects for millimeter-wave applications

This paper presents a low-cost, low-loss solution for IC-to-board interconnects using bondwires. With an L-C-L structure to compensate the influence of bondwires, low insertion loss and high return loss can be achieved. Optimized at 60 GHz, an insertion loss of 0.1 dB is achieved for the differential connection and 0.3 dB is achieved for the single-ended connection, with additional radial stubs to compensate the influence of the ground bondwire. The 1-dB bandwidth of the interconnect is larger than 10 GHz (16% relative bandwidth at 60 GHz). The low-cost and low-loss characteristic makes the interconnect well suited for millimeter-wave packaging and module design.

Wafer level integration of a 24 GHz and 34 GHz differential SiGe-MMIC oscillator with a loop antenna on a BCB membrane

The wafer level integration of a 24 GHz and 34 GHz SiGe-MMIC oscillator with buffer amplifier and a loop antenna on a BCB (Benzo Cyclo Butene) membrane is demonstrated. The phase noise of the non-integrated 24 GHz and 34 GHz oscillator is -104 dBc/Hz and -88 dBc/Hz at an offset frequency of 1 MHz and the output power was measured to be +1 dBm and -3 dBm, respectively. The radiated power of both integrated systems is determined based on measurements with a horn antenna and discussed.

Isolation issues in multifunctional Si/SiGe ICs at 24 GHz

In this paper, the authors present the study of isolation issues appearing within circuits realized on 20 Ωcm silicon substrate and at high frequencies. Several aspects of substrate noise injection and reception have beenanalyzed. Experimental results, based on test structures, have been used to give an estimate of substrate coupling noise influence. Several techniques are described in order to improve the isolation within circuits. The isolation in a fully integrated, fully differential 24 GHz oscillator/16:1 divider block, which uses these methods, is presented.

A fully monolithic 3.1-10.6 GHz UWB Si/SiGe HBT Impulse-UWB correlation receiver

A 3.1-to-10.6 GHz Impulse-UWB correlation receiver in a 0.8 mum Si/SiGe HBT technology is presented. The fully monolithic receiver with 0.8mm2 chip size comprises a low-noise amplifier with maximum noise figure of 3.2 dB, two single-ended to differential converters, an analog correlator and a template pulse generator approximating the fifth-derivative of a Gaussian impulse. It operates with pulse repetition rates up to 900 MHz (IF bandwidth limited) with a total power consumption of 200 mW.

56 GHz bandwidth FMCW radar sensor with on-chip antennas in SiGe BiCMOS

This paper presents the design and characterization of an ultra wideband FMCW radar sensor. The radar frontend consists of transmitter and receiver chips in SiGe BiCMOS technology with on-chip antennas. Both chips share the same reference chirp signal, multiplied 8 times to the desired operation band. The radar frontend demonstrates a bandwidth of 56.8 GHz from 104.4 GHz to 161.2 GHz, which corresponds to a theoretical range resolution of 2.6mm. The on-chip antenna occupies only 1.2 × 0.9mm2 without any post-micromachining and exhibits a measured gain above 4 dBi for more than 28 GHz of bandwidth. The sensor covers a bandwidth from 105 to 160 GHz with about 10 dB Tx-to-Rx gain fluctuation and less than 39 dBc harmonic power. The radar sensor was tested with FMCW chirps for different scenarios, showing a range resolution of approximately 5 mm.