The Infona portal uses cookies, i.e. strings of text saved by a browser on the user's device. The portal can access those files and use them to remember the user's data, such as their chosen settings (screen view, interface language, etc.), or their login data. By using the Infona portal the user accepts automatic saving and using this information for portal operation purposes. More information on the subject can be found in the Privacy Policy and Terms of Service. By closing this window the user confirms that they have read the information on cookie usage, and they accept the privacy policy and the way cookies are used by the portal. You can change the cookie settings in your browser.
In this work we introduce a planar ground-free terahertz absorber suitable for large-area manufacturing. The lack of a ground plane in the absorber design may pave the way for frequency-selective response that is an essential requirement for invisible sensors and wave filters. The absorber is to be manufactured using state-of-the-art techniques of large-area printing, within the frame of a joint project...
Thin beams with high spatial resolution are widely used in different measurement systems. This paper is devoted to a brief overview of the new and alternative to known approaches to the development of mesoscale systems for localization and transport of electromagnetic fields to the subwavelength region. Our approach is based on mesoscale dielectric particles of arbitrary three-dimensional shape. Its...
Array of field-effect transistors (FET) with asymmetric T-gates and floating electrodes fabricated on a single chip was used as terahertz (THz) detector. Nonresonant detection with strong photovoltaic response was realized due to excitation of electron plasma oscillations in the common channel of the FETs array. Voltage responsivities obtained by the array of FETs with floating electrodes surpass...
This paper presents a quasi-spiral THz antenna which acts as an Infrared (IR) Fresnel zone plate lens. This antenna can be the base for compact THz — IR integrated dual band sensors. The proposed configuration consists of a submillimeter wave antenna (working at around 400 GHz) which acts as a modified Fresnel Zone Plate lens for the in the IR range (around 28 THz).
This paper presents a 0.325-THz single-ended amplifier designed in a 28-nm FDSOI CMOS technology. The amplifier consists of four common-source gain stages and utilizes staggered-tuning along with inductive feedback (drain to gate) technique to boost up the gain over a wide frequency band. Having a total power consumption of 28 mW, the amplifier achieves a peak gain of 4.5 dB at 325 GHz. To the best...
This paper describes the design and performance of compact integrated sub-millimeter wave heterodyne receivers for CubeSat platforms. Examples are given of receivers produced for 183 GHz and 874 GHz atmospheric science applications. It is described how these receivers further enable more sophisticated architectures for sub-millimeter nanosatellite receivers, including polarimeters and correlation...
A wide-locking range divide-by-4 static frequency divider for the mm-wave wireless applications is proposed. The capacitive-bridged inductive shunt peaking technique is investigated for widening the locking range and a compact layout area. The divider is realized in 65nm LP CMOS with a small area of 100μm × 160μm occupied. Measurement results show the present divider achieves an operation range percentage...
Phase shifting in a dielectric rod waveguide, loaded with a carbon nanotube layer illuminated with light from a tungsten lamp, was studied experimentally at the frequency range of 75–110 GHz. Close to a linear dependence of phase shift on the optical power intensity with almost independent behavior of the losses is observed The phase shift of 30 degrees with less than 1 dB extra loss for 1.26 mW/mm2...
We are developing two prototype millimeter-wave radars at 95 and 183 GHz with a frequency-modulated continuous-wave (FMCW) architecture. The 95 GHz radar is intended to measure distributions and velocities of small particles in space, such as those ejected in cometary jets. The 183 GHz radar is to operate across the atmospheric water absorption line to perform humidity sounding inside clouds. Here...
Ihis paper describes the design and development of a single-sideband receiver using semiconductor Schottky and MMIC technology operating at room temperature from 67 GHz to 116 GHz to meet the extended frequency range of ALMA Band 2&3 simultaneously. Special care has been taken to design a fundamental balanced mixer that is sensitive from cut-off frequency up to second propagation mode of the WR-10...
This paper presents the results from evaluation of suitable materials and ink properties for printing millimeter wave components. Dielectric parameters (relative permittivity and loss tangent) of various potential substrate materials are extracted from S-parameter measurements and simulations. Test samples have been printed over Polyethylene Terephthalate (PET) and Polyethylene Naphthalate (PEN) substrates...
In this paper we present imaging results obtained from frequency modulated continuous wave radar setup operated at 650 GHz and optimized for imaging of objects with lateral dimensions between 1–20 cm. We consider in particular the ability and the benefits of using such system for resolving features corresponding to depth variations smaller than the standard depth resolution of FMCW systems. This is...
Wave propagation in a dielectric rod waveguide loaded with a layer of silver nanowires was studied experimentally at millimeter wave frequencies. Then based on the measurement results, analytical calculations were used to estimate conductivity of the silver nanowire layer at millimeter wave frequencies. Numerical simulations based on the calculated conductivities were performed and good agreement...
A compact E-band (71–76 GHz) conductor-backed coplanar waveguide (CBCPW) to hollow metallic waveguide (WR-12) transition has been designed and fabricated. The fully-planar two-layer transition makes use of a double-slot antenna, which efficiently couples the millimeter-wave (mm-wave) signal from the CBCPW to the WR-12 waveguide. The introduced transition, together with an integrated high-speed balanced...
Presented is an 89 GHz waveguide coupled direct detector based on ACST low-barrier Schottky diodes. Signal-to-noise ratio (SNR) values above 35 dB within 6 dB input power dynamic are achieved with high voltage responsivity of 3000 V/W and significant white and 1/f noise reduction. The fabricated detector is characterized and compared to simulation results, proving a high accuracy level of the design...
This paper reports the development of a cryogenic wideband low-noise amplifier based on a 50-nm metamorphic high-electron-mobility transistor process on gallium arsenide substrates. The amplifier exhibits an average gain of 22.0 dB and a noise temperature of 49 K at an ambient temperature of 15 K in the frequency range 67–116 GHz. The minimum noise temperature of 34 K is reached at the frequency of...
Biomass material is getting importance thanks to the new developments done in the energetic sector. Quality control is of great interest to optimize its production. Moisture level quality control of the product is a key point in this sector. Therefore, taking advantage of the sensibility presented by THz waves to water, a viability study to control the water content in biomass material in THz frequencies...
We propose an image rejection type direct RF undersampling receiver. By using a direct RF I/Q sample and hold (S/H) circuits, and 90 degree power combiners in the digital domain, upper side band (USB) and lower side band (LSB) signals can be separated into two different (USB and LSB) output ports, therefore the image rejection functionality can be realized with half of the clock frequency of the conventional...
Set the date range to filter the displayed results. You can set a starting date, ending date or both. You can enter the dates manually or choose them from the calendar.