Characterization of the Dielectric Properties of Commercially Available Low-loss UV-curable Resins from 60 GHz to 90 GHz

In this paper, two important dielectric properties, the relative permittivity and the loss tangent of a new commercially available UV-curable SLA resin sample are determined. The characterization of the dielectric material is performed in the millimetre-wave range using an open-cavity Fabry-Perot resonator. According to the manufacturer’s data ´...

Enhancement of Penetration of Millimeter Waves by Field Focusing Applied to Breast Cancer Detection

Objective: The potentialities of improving the penetration of millimeter waves for breast cancer imaging are here explored. Methods: A field focusing technique based on a convex optimization method is proposed, capable of increasing the field level inside a breast-emulating stratification. Results: The theoretical results are numerically...

220-GHz imaging radar with 1-Hz frame rate using an array of homodyne transceivers

We present a 220 GHz imaging radar prototype that has been developed in the European Defense Agency (EDA) project TIPPSI. The purpose of the development was to demonstrate short-range high-resolution 3D imaging for security applications at checkpoints, and to guide the development of stand-off real-time millimeter wave and sub-millimeter wave...

Gaia: Focus, straylight and basic angle

The Gaia all-sky astrometric survey is challenged by several issues affecting the spacecraft stability. Amongst them, we find the focus evolution, straylight and basic angle variations Contrary to pre-launch expectations, the image quality is continuously evolving, during commissioning and the nominal mission. Payload decontaminations and...

On the performance of the Gaia auto-collimating flat mirror assembly: Could it be even better?

The Auto-collimating Flat Mirror Assembly (AFMA) simulated the rotation of the Gaia satellite around its vertical axis. As such, it was one of the most important ground support equipment tools to test the payload performance of the Gaia mission. Although the performance of TNO's design during commissioning was excellent, one of the challenges of...

Dimensional stability testing in thermal vacuum of the CHEOPS optical telescope assembly

The CHEOPS mission (CHaracterising ExOPlanet Satellite) is dedicated to searching for exoplanetary transits by performing ultra-high precision photometry on bright stars already known to host planets. A 32cm diameter on-axis Ritchey-Chrétien telescope is used for imaging onto a single cooled detector. With integration times up to 48 hours the...

Observations and modeling of fog by cloud radar and optical sensors

Fog is a significant factor affecting the public traffic because visibility is reduced to a large extent. Therefore the determination of optical visibility in fog from radar instruments has received much interest. To observe fog with radar, high frequency bands (millimeter waves) have the best option. A 35 GHz cloud radar at the Cabauw...

Gaia on-board metrology: Basic angle and best focus

The Gaia payload ensures maximum passive stability using a single material, SiC, for most of its elements. Dedicated metrology instruments are, however, required to carry out two functions: monitoring the basic angle and refocusing the telescope. Two interferometers fed by the same laser are used to measure the basic angle changes at the level...

Observations and modeling of fog by cloud radar and optical sensors

Fog is a significant factor affecting the public traffic because visibility is reduced to a large extent. Therefore the determination of optical visibility in fog from radar instruments has received much interest. To observe fog with radar, high frequency bands (millimeter waves) have the best option. A 35 GHz cloud radar at the Cabauw...

SPEX: the SPectropolarimeter for planetary EXploration

SPEX (Spectropolarimeter for Planetary EXploration) is an innovative, compact instrument for spectropolarimetry, and in particular for detecting and characterizing aerosols in planetary atmospheres. With its ∼1-liter volume it is capable of full linear spectropolarimetry, without moving parts. The degree and angle of linear polarization of the...

The E-NIS instrument on-board the ESA Euclid Dark Energy Mission: a general view after positive conclusion of the assesment phase

The Euclid Near-Infrared Spectrometer (E-NIS) Instrument was conceived as the spectroscopic probe on-board the ESA Dark Energy Mission Euclid. Together with the Euclid Imaging Channel (EIC) in its Visible (VIS) and Near Infrared (NIP) declinations, NIS formed part of the Euclid Mission Concept derived in assessment phase and submitted to the...

Magnetic island localization for NTM control by ECE viewed along the same optical path of the ECCD beam

Neoclassical tearing modes (NTMs) deteriorate highpressure tokamak plasma confinement and can be suppressed by electron cyclotron current drive (ECCD). In order to obtain efficient suppression, the ECCD power needs to be deposited at the center of an NTM magnetic island. To enhance efficiency, this power also needs to be synchronized in phase...

Enhanced MAC Layer Protocol for Millimeter Wave based WPAN

The IEEE 802.15.3 standard defines a widely-accepted MAC layer protocol for high data rate WPANs. However, resource allocation schemes are not specified in the IEEE 802.15.3 MAC. In this paper, an enhanced IEEE 802.15.3 MAC is proposed for 60 GHz based WPANs. The enhancement relies on a novel resource management scheme. By exploiting the...

Leaky-Wave Slot Array Antenna Fed by a Dual Reflector System

A leaky-wave slot array antenna fed by a dual offset Gregorian reflector system is realized by pins in a parallel plate waveguide. The radiating part of the antenna is composed by parallel slots etched on one side of the same parallel plate waveguide. The dual offset Gregorian reflector system is fed by an arrangement constituted by two vias and...

EBG enhanced dielectric lens antennas for the imaging at sub-mm waves

We have designed a novel sub-mm radiation detector based upon a twin slot antenna placed in the focus of a Si elliptical lens. We use a novel Electromagnetic Band Gap (EBG) super-layer, consisting of 2 1/4 gamma dielectric layers of Si (ε=11.7) and SiO2 (ε=4) and a Si carrier wafer to enhance the directivity of the feed. The antenna is coupled...

Design and Analysis of a 34 dBm Ka-Band GaN High Power Amplifier MMIC

This paper presents the design and analysis issues related to the use of recent GaN technologies for realizing high power millimeter wave MMICs. Two GaN Ka-band amplifier MMICs have been designed, fabricated and characterized. The small-signal and power measurement results are presented for both amplifiers, with an excellent output power of 34.1...

Novel organic SMD package for high-power millimeter wave MMICs

In this paper a novel low-cost SMD package for high-power MMICs is presented. Due to the special design this package has a very low thermal resistance and low parasitic ground inductance. 3D EM simulations of a packaged through-line correspond well with measurements. Measurement results of a 1 Watt 40 GHz HPA before and after packaging are...

Low-cost millimeter-wave transceiver module using SMD packaged MMICs

This paper presents a novel approach to realize low-cost millimeter-wave modules using only SMD packaged MMICs integrated on a single organic substrate. This approach is demonstrated on a 38 GHz transceiver module for point-to-point LMDS communication systems. The required SMD package technology and demonstrator have been developed in the 5th...