Laurent Dussopt

• Atomic Energy and Alternative Energies Commission

Characterization of the magnetic fields at different scales in the Universe is a new frontier for submillimeter astronomy. Polarimetric measurements between 50 and 500 µm are the golden path for this research. We develop, in the prospect of space observatories, all-silicon 50 mK bolometer arrays with polarimetric capabilities in the pixel. Here, we...

We are studying and developing high-performance spectroscopy solutions in silicon technology in the framework of instrumental developments around the B-BOP bolometer arrays and in the continuation of the former developments of the Herschel space telescope instruments and in particular its photodetector array camera and spectrometer. The integration...

In this paper, we discuss the characterization of boron-doped silicon superconducting thin films with a thickness of 70 nm made on silicon-on-insulator substrates by ion implantation and ultra-violet nanosecond laser annealing under nitrogen at atmospheric pressure. Two different ion-implanted doses of boron of 1 × 10¹⁶ and 2.5 × 10¹⁶ cm⁻² at 3 keV...

We are studying and developing high performance spectroscopy solutions in silicon technology in the framework of the instrumental developments around the B-BOP bolometer arrays [1] and in the continuity of the former developments of the Herschel space telescope instruments and in particular its PACS instrument [2]. The integration of multi-waveleng...

In this paper, we investigate two bolometer detectors with a pixel size of 500 µm and 1200 µm to address, respectively, the 0.6 mm and 1.5 mm wavelengths in order to study the temperature and polarization of cosmic microwave background (CMB). The pixels are polarization sensitive using Ti/TiN superconducting absorbers. They are deposited on suspend...

High-impedance surfaces (HIS) are investigated here for the above-IC integration of sub-millimeter-wave (350 µm here) detectors on CMOS electronics using standard thin film manufacturing processes and materials. We demonstrate theoretically and experimentally the efficient optical absorption of a resistive dipole array above an HIS at cryogenic tem...

We present the B-BOP instrument, a polarimetric camera on board the future ESA-JAXA SPICA far-infrared space observatory. B-BOP will allow the study of the magnetic field in various astrophysical environments thanks to its unprecedented ability to measure the linear polarization of the submillimeter light. The maps produced by B-BOP will contain no...

substrate-integrated discrete-lens antenna manufactured in standard printed-circuit-board (PCB) techno-logy is demonstrated in H-band (225–325 GHz). The arrays composed of phase-shifting unit-cells and a waveguide-fed planar focal source are designed on a single PCB stack with five metal layers and multiple low-loss dielectric substrates in a monol...

The thermal sensitivity and Low Frequency Noise (LFN) of compensation doped Silicon-On-Insulator (SOI) resistors are studied experimentally, down to the cryogenic regime. A high compensation nominal ratio ${K}={N}_{A}/{N}_{D}$ of 0.82 is compared with uncompensated and partially compensated configurations, using Phosphorus and Boron as dopant spe...

This paper presents the experimental results of a 2-bit electronically reconfigurable unit-cell for transmitarrays at Ka-band. The proposed unit-cell architecture is based on a six-metal layers design and three dielectric substrates. Two patch antennas are printed respectively on the top and bottom layers of the stack-up to achieve an antenna-filte...

The thermometric behavior of lateral 50-nm thin Silicon-On-Insulator (SOI) diodes are studied down to 80 K, close to liquid-nitrogen temperature. A comparison between PtSi/n-Si Schottky and implanted p-i-n diodes is presented. In this study, the intrinsic region is a moderately-doped n-type region. Key figures are extracted at room and cryogenic te...

This paper reports our results on the electrothermal modeling of cryogenic silicon bolometers with pixel pitches of 500 and 1200 µm designed for cosmic microwave background polarimetric observation in 0.6 mm and 1.5 mm bands. These detectors should provide a high responsivity, typically around 1011 V/W, and a very low noise equivalent power (NEP) o...

This paper presents the design, optimization, fabrication, and characterization of an electronically steerable transmitarray with 2 bits of phase quantization per unit cell. The proposed transmitarray operates in linear polarization at Ka-band and is composed of 14W14 reconfigurable unit-cells. Four p-i-n diodes are integrated on each unit-cell to...

This paper presents the design and demonstration of Gaussian-beam transmitarray antennas at millimeter-wave frequencies. The main design trade-offs and theoretical performances are first investigated numerically. Next, two antenna prototypes are designed in V band and fabricated in printed-circuit-board technology. These prototypes are validated ex...

The first observation of coherent elastic neutrino-nucleus scattering (CEνNS), reported by the COHERENT Collaboration in 2017, paved the way for a new generation of experiments using reactor ν̄e and aiming at precisely measuring this process. In this context, the BASKET (Bolometers At Sub-KeV Energy Thresholds) R&D project investigates the use of c...

We present here a design of metal-only unit-cell for transmitarray antenna (TA) applications at Ka-band, and we introduce a solution to reduce the total number of layers by polarization manipulation. The corresponding unit-cell is based on a C-shaped slot radiating element, fabricated by laser ablation on a thin metal sheet and operating in linear...

In this paper, we present a synthesis procedure for the optimization of transmitarray antennas based on a hybrid analytical tool and genetic algorithm. The design of a single-feed quad-beam circularly-polarized transmitarray is presented in detail as a test case example. This discussion also includes experimental results. The proposed antenna is op...

The Space Infrared telescope for Cosmology and Astrophysics (SPICA) mission has just been selected by the European Space Agency as one of the three candidate missions to be further studied for the medium size mission M5. B-BOP, formerly named POL, is one of the three scientific instruments of SPICA which aims, among other scientific goals, to map t...

Polarization-sensitive detectors at 120–500 GHz are required for the observation of the cosmic microwave background radiation. In this paper, superconducting thin films based on Ti/TiN bilayers are developed to be integrated as electromagnetic wave absorbers in suspended cooled silicon bolometers. The critical temperature (Tc) is tuned in the range...

We propose here an experimental characterization procedure applied to a 1-bit reconfigurable transmitarray unit-cell working in circular polarization at Ka-band. The transmission phase of the unit-cell is controlled on the receiving side by switching two p-i-n diodes integrated on the radiating element. The circular polarization is generated on the...

Understanding the origin and early evolution of stars is one of the fundamental objectives of astronomy. This can be possible with observations made from space in the mid- to far-infrared and millimeter-wave part of the spectrum which require detectors with very high sensitivity. In the framework of the SPICA project and the course of developing co...

A high-sensitivity cryogenic sub-millimetre camera is planned for the SPICA space observatory. At the heart of this instrument, new all-silicon bolometer arrays integrate in pixel instrumental polarimetry capabilities. © 2018 Springer Science+Business Media, LLC, part of Springer Nature

In the frame of the SPICA mission, new semiconductor bolometers have been designed for the POL instrument which is directly part of the HERSCHEL/PACS legacy. These detectors are cooled down to 50 mK and are sensitive to polarization for the 100, 200 and 350 μm wavelength bands. In this paper, 3D simulations have been carried out with the COMSOL Mul...

This letter presents the simulation, optimization, and demonstration of a collimated-beam transmitarray and a quad-beam transmitarray operating at Ka-band. Both transmitarrays are based on a 3 bit unit cell implementing both phase-shift and linear-to-circular polarization conversion functions. The collimated-beam transmitarray presents a measured g...

Transmitarray antennas have attracted a lot of interest for the last 10 years to address the challenges of high-directivity reconfigurable antenna designs for emerging applications at millimeter-wave frequencies. This chapter presents the main principles of operation of transmitarray antennas, their main advantages and challenges, and typical envis...

A novel topology of high-gain millimeter-wave antenna compatible with substrate integration is presented. The antenna is composed of a planar discrete lens laid on top of a core dielectric, while the planar focal source is assembled on the bottom side. The antenna can be fabricated as a single, robust and compact module using standard low-cost PCB...

The development of millimeter-wave (mmW) technologies comes with concerns related to the user exposure. A detailed numerical dosimetry study is performed for a terminal with a 60-GHz antenna module for several representative human body exposure scenarios within 5G small cells. First, numerical considerations are made regarding the user terminal and...

CEA has a long history of customizing optoelectronic components for space and astronomy applications. With this expertise we are undertaking a development of cooled silicon bolometers for millimeter (mm) wave polarization detection, typically at λ=1.5 mm, in order to address the next generation of space astronomy missions. This work presents the ea...

Dual-band transmitarray antennas are demonstrated at Ka-band with the capability of forming independent linearly-polarized beams with a given polarization in each frequency band, while sharing the same radiating aperture. The proposed three-layer unit-cell is based on identical narrow microstrip patches printed on both receiving and transmitting la...

Mobile communication technology has been rapidly evolving ever since its first introduction in the late 1980s. The development witnessed is not just in the refinement of the radio access techniques, but also in the progression towards offering sophisticated features and services to the mobile phone users. To fulfill this ever-growing user demand an...

A V-band, switched-beam, linearly-polarized transmit-array antenna enabling self-pointing point-to-point communication systems, e.g. wireless backhaul applications in future mobile networks is presented. The antenna is designed and fabricated using standard PCB materials and processes as well as commercially available switches. The design and chara...

Dans ce papier, l'impact de la méthode de compensation de phase sur les performances des réseaux transmetteurs est analysé. Un modèle numérique du réseau transmetteur est considéré pour les études réalisées. Ce modèle est basé sur des cellules élémentaires et une source focale (10 dBi de gain) théoriques (100% de rendement). La loi de compensation...

The design, realization and experimental characterization of a 400-element electronically-reconfigurable transmitarray operating in Ka-band is presented. It is based on linearly-polarized unit-cells with 180° phase-shifting capability. Several sequential rotation schemes have been compared numerically to generate a circularly-polarized beam over a...

This paper shows a passive broad-band SPDT T/R switch in 55-nm BiCMOS technology which covers most of the millimetre-wave bands considered for 5G (from 28 to 86 GHz). It is intended to be integrated into active phased array antenna modules for a 5G small cell access link. The realized switch presents minimum insertion loss of 2.6 dB. The switch iso...

In this contribution, we propose a new reconfigurable unit-cell design operating in circular polarization in Ka-band. Two p-i-n diodes are integrated in order to achieve a phase resolution of 1 bit (0°/180° are the possible phase states). An insertion loss of about 1 dB at 29 GHz with a 3-dB relative bandwidth of 14.5% has been numerically demonstr...

Dual linearly polarized transmitarray antennas with wideband performance are investigated in X-band. Their designs are based on unit-cells with bandpass response. Their structures consist of three conducting layers printed on two identical dielectric substrates glued with a bonding film. Detailed experimental results demonstrate excellent polarizat...

Mobile communication technology has been rapidly evolving ever since its first introduction in the late 1980s. The development witnessed is not just in the refinement of the radio access techniques, but also in the progression towards offering sophisticated features and services to the mobile phone users. To fulfill this ever-growing user demand an...

Multispectral infrared (IR) detection is of great interest to enhance our ability to gather information from a scene. Filtering is a low-cost alternative to the complex multispectral device architectures to which the IR community has devoted much attention. Multilayer dielectric filters are standard in industry, but they require changing the thickn...

In this contribution, we present the design of a 400-element electronically reconfigurable transmitarray working in Ka-band with 180° phase-shifting unit-cells. The sequential rotation technique is applied to generate a circularly-polarized beam over a broad frequency band. The proposed configuration exhibits a broadside gain of 20.3 dBi at 29.0GHz...

In this contribution, we study the design and experimental characterization of a reconfigurable transmitarray in X-band with reduced focal distance. To this end, we consider an illumination with four feed horn antennas in two different configurations. The focal distance and the horn configuration in the focal plane have been optimized with an in-ho...

3D integration came as a response to the requirements of high performance and small footprint electronic devices. Today, the need for more heterogeneous integration schemes with increased functionalities becomes more obvious as the three worlds of digital, analog/mixed-signal (AMS) and RF electronics are converging. High performance computing, mili...

We present here the design and demonstration of a circularly polarized (CP) transmitarray antenna operating in Ka-band and illuminated by a linearly polarized (LP) source. The proposed design is based on a CP unit-cell with simulated insertion loss of 0.2 dB at 30 GHz. In order to improve the axial ratio (AR) bandwidth, the sequential rotation tech...

Applications are increasingly becoming more sophisticated and rich in content, requiring more capable devices with higher energy requirements. This provides the impetus for an overhaul of the design process to engineer future emerging handsets to include energy efficiency as an optimization metric, complementing legacy design goals that include mul...

Legacy mobile handsets already incorporate multimode features, with dual, tri and quad band functionality already the norm, and the very latest smart phone having WiFi connectivity. However, complete interoperability is still in its infancy with several hurdles still to overcome, and energy efficiency is one of them. Unless mobile handsets are smar...

Next generation handsets will need to be energy aware so as to support 5G services, that are likely to be intelligent and bandwidth hungry, as well as support multi-mode operation (LTE, LTE+, HSDPA, 3G, WiFi among others) in Heterogeneous Networking (HetNet) environment. This vision gives way to stringent design requirements on the RF system design...

Millimeter-waves are expected to play a key role in next 5G scenario due to the availability of a large clean unlicensed bandwidth at 60 GHz and the possibility to realize packed antenna arrays, with a consequent increase of the communication capacity and the introduction of new functionalities, such as high-definition localization and personal rad...

In this contribution, we propose the design of a circularly-polarized reconfigurable transmitarray based on a 1-bit unit-cell (i.e. with two phase states, 0° and 180°) operating in linear polarization. Applying the sequential rotation technique, the possibility to switch between the two circular (LHCP/RHCP) polarizations will be presented. The nume...

We present here the characterization of a 1-bit linearly-polarized reconfigurable 20×20-element transmitarray operating in X-band with a reduced focal distance. The array is illuminated by four 10-dBi horns excited in phase and whose positions have been optimized; this leads to a 45% reduction of the focal distance. The numerical results are valida...

In the context of the fast development of millimeter-wave (mmW) technologies for future 5G cellular networks and concerns related to their possible impact on the human health, this paper introduces a first analysis on the mmWs interaction with the human body. Firstly, the main regulations on the exposure limits at mmWs are reviewed. Secondly, an in...

A 60-GHz transceiver module fully integrated on silicon interposer technology is demonstrated for the first time. The module includes a 65-nm CMOS RFIC transceiver and two antennas (transmit, receive) in a very compact volume (6.5×6.5×0.6 mm3). The fabrication process is presented. The design and measurements of the antenna demonstrate very good pe...

We investigate here the capabilities of a 400-element reconfigurable transmitarray antenna to synthesize monopulse radiation patterns for radar applications in X-band. The generation of the sum (Sigma) and difference (Delta) patterns are demonstrated both theoretically and experimentally for broadside as well as tilted beams in different azimuthal...

The invention relates to a method for measuring the permittivity and/or perviousness of a sample of a nonconductive material, said method comprising: a) measuring a value representative of an admittance Ytestco, b) measuring a value representative of an admittance Ytestcc only from the amplitude and the phase of the electromagnetic waves reflected...

This letter presents an electronically reconfigurable, linearly polarized unit cell for transmitarray applications in Ka-band. A 1-bit phase resolution (namely with two phase states 0° and 180°) is obtained using two p-i-n diodes mounted on a slot-loaded patch antenna. The design, realization, and experimental characterization in a standard wavegui...