Two frequency-tripler monolithic microwave integrated circuits (MMICs) reaching sub-millimeter-wave output frequencies of 315 GHz are presented. The convenient integration of transistor–based field effect transistor (FET) frequency multipliers into multifunctional MMICs is shown by integration of a single–stage frequency-tripler with a buffer amplifier generating −0.5 dBm of peak output power at 288. Without post-amplification an average output power of −10.1 dBm in the output frequency range from 285 to 315 is measured with 10 dBm of input power. The 3-dB bandwidth is more than 30 GHz and could not be determined exactly due to the measurement setup. Both MMICs are realized in a 50 nm metamorphic high electron mobility transistor (HEMT) transistor technology. A multiple power-meter measurement technique including a waveguide filter is used to measure accurately the second harmonic power content within the output spectrum.

In this paper we present the design and realization of a high-power amplifier in grounded coplanar transmission line technology using AlGaN/GaN dual-gate High electron mobility transistors (HEMTs) with a gate-length of 100 nm to achieve a high gain per stage and high output power. A large-signal model was extracted for the dual-gate HEMT based on the state-space approach. For the fabricated dual-stage amplifier a continuous-wave saturatedoutput power of up to 24.8 dBm (0.84 W/mm) was measured at 63 GHz for 20 V drain bias. A small-signal gain of more than 20 dB was achieved between 56 and 65 GHz.

We present a method to realize a low-power and high-speed digital-to-analog converter (DAC) for system-on-chip applications. The new method is a combination of binary-weighted current cells and R-2R ladder and is specially suited for modern BiCMOS technologies. A prototype 5 GS/s DAC is implemented in 0.13 μm SiGe BiCMOS technology. The DAC dissipates 26 mW and provides an SFDR higher than 48 dB for output frequencies up to 1 GHz.

We report cryogenic noise temperature and gain measurements of a prototype heterodyne receiver module designed to operate in the atmospheric window centered on 150 GHz. The module utilizes monolithic microwave integrated circuit (MMIC) InP high electron mobility transistor (HEMT) amplifiers, a second harmonic mixer, and bandpass filters. Swept local oscillator (LO) measurements show an average gain of 22 dB and an average noise temperature of 87 K over a 40 GHz band from 140 to 180 GHz when the module is cooled to 22 K. A spot noise temperature of 58 K was measured at 166 GHz and is a record for cryogenic noise from HEMT amplifiers at this frequency. Intermediate frequency (IF) sweep measurements show a 20 GHz IF band with less than 94 K receiver noise temperature for a fixed LO of 83 GHz. The compact housing features a split-block design that facilitates quick assembly and a condensed arrangement of the MMIC components and bias circuitry. DC feedthroughs and nano-miniature connectors also contribute to the compact design, so that the dimensions of the moduleare approximately 2.5 cm per side.

In this paper we present a wireless data link for multi-gigabit transmission in the mmW frequency range. The link is realized using waveguide modules based on fully integrated 50 nm metamorphic high electron mobility transistor (mHEMT) transmit and receive millimeter wave monolithic integrated circuits (MMICs) and provides transmission of data rates up to 12.5 Gbit/s modulated on a 220 GHz carrier. The receiver input sensitivity is characterized down to values of −38.6 dBm and shows an error rate of 3.0 × 10−9. Measurements using a coherent link setup show bit error rates better than 1.6 × 10−9 for a data rate of 10 Gbit/s and a transmission distance of 2 m. For a distance of 20 m a real-time Digital Video Broadcasting – Satellite (DVB-S) television transmission is realized. The signal quality after the wireless link is sufficient for a commercial DVB-S receiver to display the television programs.

We report on the development of W-band (75–110 GHz) heterodyne receiver technology for large-format astronomical arrays. The receiver system is designed to be both mass producible, so that the designs could be scaled to thousands of receiver elements, and modular. Most of the receiver functionality is integrated into compact monolithic microwave integrated circuit (MMIC) amplifier-based multichip modules. The MMIC modules include a chain of InP MMIC low-noise amplifiers, coupled-line bandpass filters, and sub-harmonic Schottky diode mixers. The receiver signals will be routed to and from the MMIC modules on a multilayer high-frequency laminate, which includes splitters, amplifiers, and frequency triplers. A prototype MMIC module has exhibited a band-averaged noise temperature of 41 K from 82 to 100 GHz and a gain of 29 dB at 15 K, which is the state-of-the-art for heterodyne multichip modules.

This paper presents a frequency-modulated continuous-wave (FMCW) radar operating at 120 GHz, which features silicon–germanium (SiGe) chips that employ HBTs with 320 GHz fmax. The chipset comprises a fundamental-wave signal-generation chip with a voltage-controlled oscillator (VCO) that provides frequencies between 114 and 130 GHz and a corresponding dual–transceiver (TRX) chip that supports monostatic and quasi-monostatic radar configurations. The cascode amplifiers used in the TRX chip were characterized in separate test chips and yielded peak small-signal gains of approximately 15 dB. Finally, a quasi-monostatic two-channel FMCW radar frontend with on-board differential microstrip antennas was built on an RF substrate. FMCW radar measurements with frequency chirps from 116 to 123 GHz verified the functionality of the designed radar sensor.

The paper is a joint work between the LEAT (France) and the ENRI (Japan) in the framework of a Sakura project supported by the JSPS and the French Ministry of Foreign Affairs. The purpose is the study of a FOD (Foreign Object Debris) detection system on airport runways. An FM-CW mm-wave radar working between 76.25 and 76.75 GHz is used together with a high directivity printed reflectarray. In addition, a second measurement campaign has been conducted with a 73.8–79.8 GHz (6 GHz band) radar. Measurement results show detection capabilities of a −20 dBsm cylinder up to 35 m that is 10 m less than the FAA recommendations. Antenna improvements are discussed for reaching the requirements and system performance as well as the use of calibration objects.

This paper introduces a radar system for three-dimensional (3D) object detection and imaging. The presented 3D measurement method combines the frequency-modulated continuous wave (FMCW) approach for range measurements with a multiple-input multiple-output (MIMO) technique for digital beamforming in two dimensions. With an orthogonal arrangement of the antenna arrays for transmit and receive, the angular information is obtained in azimuth and elevation without mechanical beamsteering. The proposed principle allows performing 3D imaging by means of the acquired range, azimuth, and elevation information with a minimum of required hardware. Starting from the realization of the 3D radar imaging concept, the hardware architecture and the developed prototype are discussed in detail. Furthermore, the object detection capability of the 3D imaging radar system is demonstrated by measurements. The results show that the introduced 3D measurement concept in its realization is well suited for numerous applications.

In this paper, we are concerned on the receiver design and the different imaging possibilities for radar multiple input multiple output (MIMO) synthetic aperture radar (SAR). The transmission of pseudo-orthogonal waveforms gives many opportunities in reception on how to manage these different signals. We proposed to compare different resolutions and robustness for SAR measurements: single input single output (SISO) and MIMO. Moreover, we developed different SAR processings based on MIMO configuration by using the Stolt interpolation on simulations. On real data, these SAR processing will be adapted for the backprojection processing.

A dielectric waveguide-based structure coupled to a whispering gallery mode (WGM) disc resonator is introduced as a low-cost integrable millimeter-wave (mm-wave) bio-sensor. An efficient variational analysis method is developed and applied to the WGM. Three sets of sensors, operating in different ranges of frequency from 85 to 220 GHz, are fabricated and tested. The performance of the fabricated bio-sensor is demonstrated for sensing different concentrations of glucose solution samples at D-band. Also, the sensitivity, selectivity, and repeatability of these sensors are examined.

Delay time measurements are a commonly used technique for the characterization of dielectric materials. Especially with regard to the characterization of water–solid mixtures like soil or grain delay time measurements, e.g., time domain reflectometry offers a powerful method. However, the accuracy of reflection measurements is limited due to multiple reflections caused by inhomogenities of the environmental material of the sensor. This contribution deals with an improved sensor design based on time domain transmission (TDT) measurements. Thus, the first received impulse includes the necessary information. Multiple reflections are received at later time steps and their influence on the measurement accuracy is nearly negligible. To improve the performance and the applicability of the designed sensor, a cost–efficient TDT system is designed, which is integrated in the sensor. Additionally, a so-called “concentric reversion coupler” is used, which offers the possibility to perform TDT measurements without the necessity of external measuring ports.

This paper considers and compares the numerical characterization of regular planar antenna arrays from two viewpoints. In the case where the array is sufficiently large, the well-known infinite array idealization applies and a very efficient simulation method is presented which combines array theory with a specialized form of the finite-element method called the transfinite element method (TFEM). Alternatively, a more direct approach is discussed in which the entire antenna array is simulated as a finite structure using recent advances in the domain decomposition method (DDM). Taken together, the two methods provide a comprehensive simulation method for regular arrays from small order to very large order.

In this work, a very efficient mixed-potential integral-equation formulation is implemented for the rigorous analysis of multilayered structures with arbitrarily shaped two-dimensional periodic metallic and/or dielectric inclusions. Original acceleration techniques have been developed for the computation of the components of the scalar and dyadic Green's functions, based on different types of asymptotic extractions according to the potential considered. The theoretical approach and its computational convenience have been validated through different full-wave analyses concerning both scattering problems and complex-mode dispersive behaviors in various frequency-selective structures for microwave applications.

This paper describes the design of high-performance compact aperture array antennas for radio astronomy and other applications. Three recent antenna developments for square kilometer array design study (SKADS) have been investigated and the performances are compared. In addition to the radio frequency (RF) performance, an essential requirement for the square kilometer array application is the cost per square area. Based on initial large–scale finite array studies, prototypes with different geometries have been fabricated and measured. Guidelines are derived for large–scale wide–band dual-polarized array designs in applications where low cross-polarization and a wide range of scan angles are required.

In this paper, we present a continuously tunable phase shifter realized in MEMS technology. Varactors with liquid crystal as a tunable dielectric layer underneath gold bridges are used to build a loaded line phase shifter. Measurements show that the phase shifter has a differential phase shift of 92°, a figure of merit (FoM) of 42°/dB and an input matching of −19 dB at 76 GHz.The tuning speed of the phase shifter is measured at different temperatures between 10 and 50°C. The realized phase shifter can be used in combination with MEMS switches in order to build a 360° tunable reflection phase shifter.

A new setup is proposed for the measurement of current–voltage pulsed characteristics of electron devices. The main advantages of the system consist in: shorter pulse widths through generation in a 50-Ω environment, simple average current monitoring through separation of the direct and alternate current paths, setting of average voltage values independently of pulse amplitudes and duty cycle, and stability of the setup guaranteed by wide-band dissipative terminations. The system is used for the characterization of dispersive effects due to carrier energy traps and thermal phenomena in GaAs and GaN on SiC field effect transistors. The basic differences between the two technologies are highlighted in the paper.

Millimeter-wave wireless space-division-multiplexing signals were discriminated by a newly developed electro-optic modulator using an array of antenna-coupled electrodes and polarization-reversed structures of ferroelectric optical crystals. Discrimination with channel isolation over 13 dB was obtained for two 38 GHz wireless signals with an irradiation angle difference of 15° by use of a fabricated device 30 mm in length.