Philipp Pahl

High-Accuracy Range Detection Radar Sensor for Hydraulic Cylinders

Industrial automation requires highly precise distance measurement sensors. Accurate detection of the piston position is indispensable for the control and monitoring of hydraulic cylinder applications. Known external and integrated solutions are subject to many limitations as for example in accuracy, in measurement length, or in price. A promising approach consists in the use of precise and low-cost radar sensors. The developed K-band frequency modulated continuous wave (FMCW) radar system in this paper detects the piston position in a hydraulic cylinder based on the guided propagation of a radar signal. The dielectric characteristics of the hydraulic oil are obtained for this purpose by permittivity measurement methods. Influences of the hydraulic oil on wave propagation in cylindrical waveguides as well as mechanical requirements associated with this new approach are investigated. The design of an adapted oil- and pressure-resistant transition between the radar sensor and the hydraulic cylinder and a novel calibration method will be described and verified under real measurement conditions. At a measurement repetition rate of 2 kHz, an accuracy of well below 200 μm was achieved for a hydraulic cylinder of 1 m in length.

Holographic mmW-Antennas With

This paper presents three different kinds of planar holographic antennas optimized for the usage in frequency-modulated-continuous-wave (FMCW)-radar systems. The antennas use different kinds of surface-wave modes (TE- and TM-modes), created by planar surface-wave launchers. Due to these feeds the antennas are very well suited for integration into millimeter-wave-systems. The radiation performance is calculated on the basis of holographic theory and the results are verified by full-wave simulations and measurements. Bidirectional radiation of the

{\rm TE}_0

{\bf{TE}}_0

and

-antennas is avoided by using artificial-magnetic-conductor (AMC) structures as antenna reflectors. This novel approach allows a holographic antenna with great integration qualifications and a highly directive and frequency-scanning main lobe and is compared with the also unidirectional

{\rm TM}_0

{\bf{TM}}_0

Surface Wave Launchers for Frequency-Scanning FMCW-Radars

-mode antenna.

Design and measurement of matched wire bond and flip chip interconnects for D-band system-in-package applications

This paper reports on possible interconnect solutions between a Silicon MMIC and an off-chip antenna. These shall both be integrated within a plastic package to achieve a 122 GHz system-in-package. Coplanar wire bond and flip chip interconnects are shortly introduced and compared. Simulation and measurement results of matched interconnects are then evaluated in a frequency range between 110 and 170 GHz. A matched 400 µm long wire bond interconnect as well as a self-matching half-wave wire bond are compared to a flip chip interconnect.

Radar-Based High-Accuracy Angle Measurement Sensor Operating in the K-Band

The growing need for high-precision measurement instruments in modern industrial facilities leads to new measurement principles to reduce sensor costs while maintaining accuracy. A novel measurement principle suited for these applications is based on radar, which originally is associated with measurements in free space. For high precision, guided waves can be used to prevent disturbing reflections from the environment. Another advantage of a waveguide-based measurement is that the electromagnetic wave can be guided in a circle to measure rotational motions, which are in particular relevant in machine tools. This paper describes an FMCW radar sensor in the K-band for angle measurements. The sensor principle is described in detail, including its high-frequency components and the mechanical constraints to achieve a full angle range of 360°. The propagation characteristics of the radar signal in a curved waveguide with an adapted feeding structure using a Riblet coupler are presented. In addition to simulations, measurements with a prototype setup are presented to verify the radar-based angle measurement principle. The achieved accuracy is ±0.05° which corresponds to an accuracy in distance of ±125 μm.

A 144 GHz power amplifier MMIC with 11 dBm output power, 10 dB associated gain and 10 % power-added efficiency

A millimeter-wave monolithic integrated circuit power amplifier operating in the frequency range between 135 and 155 GHz is presented. The D-band power amplifier, realized in a 100 nm gate length metamorphic high electron mobility transistor technology, employs a three-stage design with four parallel transistors in the output stage. At 144 GHz and under 1-dB gain compression, the amplifier achieves an output power of more than 11 dBm with an associated gain of 10 dB and a high power-added efficiency of 10%. A comparison to state-of-the-art power amplifiers at high millimeter-wave frequencies is given.

A Novel 1

For application in radar and communication systems operating in the frequency range around 250 GHz, a power amplifier (PA) millimeter-wave monolithic integrated circuit (MMIC) has been developed. The amplifier makes use of a novel coupler approach allowing for in-phase and equal-magnitude distribution of an incoming signal to four parallel output ports. This is possible due to a subtle use of grounded coplanar waveguide and air-bridge microstrip transmission lines, providing different propagation constants. With a size of quarter-wavelength, the coupler is very compact and is the key to the presented PA topology. The amplifier exploits the virtual open occurring due to the identical signals for transistor biasing and matching. The amplifier topology is applied to develop an amplifier MMIC. When biased for maximum gain, it shows a 17-GHz 3-dB bandwidth around its center frequency at 248 GHz with a maximum gain of 32.8 dB. When biased for maximum output power, it provides an output power of 10 and 8.5 dBm at 250 and 270 GHz, respectively. At 250 GHz, it demonstrates a state-of-the-art power density of 125 mW/mm. Due to the amplifier topology, the MMIC is very compact (1.25×0.75 mm2).