46 research outputs found

    An Overview of Solid-State Integrated Circuit Amplifiers in the Submillimeter-Wave and THz Regime

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    We present an overview of solid-state integrated circuit amplifiers approaching terahertz frequencies based on the latest device technologies which have emerged in the past several years. Highlights include the best reported data from heterojunction bipolar transistor (HBT) circuits, high electron mobility transistor (HEMT) circuits, and metamorphic HEMT (mHEMT) amplifier circuits. We discuss packaging techniques for the various technologies in waveguide modules and describe the best reported noise figures measured in these technologies. A consequence of THz transistors, namely ultra-low-noise at cryogenic temperatures, will be explored and results presented. We also present a short review of power amplifier technologies for the THz regime. Finally, we discuss emerging materials for THz amplifiers into the next decade

    An Overview of Solid-State Integrated Circuit Amplifiers in the Submillimeter-Wave and THz Regime

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    Space Communications: Theory and Applications. Volume 3: Information Processing and Advanced Techniques. A Bibliography, 1958 - 1963

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    Annotated bibliography on information processing and advanced communication techniques - theory and applications of space communication

    Design, fabrication, and demonstration of low-mass, low-power, small-volume, direct detection millimeter-wave radiometers at 92 and 130 GHz

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    2012 Spring.Includes bibliographical references.Advances in future ocean satellite altimetry missions are needed to meet oceanographic and hydrological objectives. These needs include accurately determining the sea surface height (SSH) on spatial scales of 10 km and larger, as well as monitoring the height of the world's inland bodies of water and the flow rate of rivers. The Surface Water and Ocean Topography (SWOT) mission was recommended by the National Research Council's Earth Science Decadal Survey and selected by the National Aeronautics and Space Administration as an accelerated Tier-2 mission to address these needs. Current surface altimetry missions use nadir pointing 18-37 GHz microwave radiometers to correct for errors in SSH due to wet-tropospheric path delay. Using current antennas at these frequencies, oceanic measurements include significant errors within 50 km of coastlines due to varying emissivity and temperature of land. Higher frequencies (90-170 GHz) can provide proportionally smaller footprints for the same antenna size. In turn, this provides improved retrievals of wet-tropospheric path delay near the coasts. This thesis will focus on the design, fabrication, and testing of two direct detection radiometers with internal calibration at center frequencies of 92 and 130 GHz. Component design, testing and integration of the radiometers using multi-chip modules are discussed. The performance of these radiometers is characterized, including noise figure, internal calibration and long-term stability. These performance parameters, along with their mass, volume, and power consumption, will be used as the basis for the development of future airborne and space-borne millimeter-wave direct detection radiometers with internal calibration

    GigaHertz Symposium 2010

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    The present situation and forecasts of semiconductor elements performance within the microwave range, 1970-1985

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    The present situation and possible developments over the period 1970-1985 for active semiconductor elements in the microwave range are outlined. After a short historical survey of FT techniques, the following are discussed: Generation, power amplification, amplification of small signals, frequency conversion, detection, electronic signal control and integrated microwave circuits

    Terahertz Technology and Its Applications

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    The Terahertz frequency range (0.1 – 10)THz has demonstrated to provide many opportunities in prominent research fields such as high-speed communications, biomedicine, sensing, and imaging. This spectral range, lying between electronics and photonics, has been historically known as “terahertz gap” because of the lack of experimental as well as fabrication technologies. However, many efforts are now being carried out worldwide in order improve technology working at this frequency range. This book represents a mechanism to highlight some of the work being done within this range of the electromagnetic spectrum. The topics covered include non-destructive testing, teraherz imaging and sensing, among others

    Far-infrared/millimeter Wave Source And Component Development For Imaging And Spectroscopy

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    The far-infrared and millimeter wave (FIR/mmW) (wavelength 75 micrometer to 10 mm) portion of the electromagnetic spectrum is fairly underdeveloped technologically, owing to the large amount of atmospheric attenuation in that range. At present, the FIR/mmW region is lacking in compact, high-brightness radiation sources and practical imaging systems. This dissertation focuses on development of two complementary technologies in this area - an active mmW imaging system and high-reflectivity Bragg mirrors for the FIR p-Ge laser. The imaging system uses a vector network analyzer in the frequency range of 90-140 GHz as the radiation source and receiver. Raster scanning is used to map a two-dimensional field of view, demonstrating the detection and imaging of buried plastic landmines. Principal components analysis is used for hyperspectral signal processing, where a series of images is taken at discrete frequencies. Results are obtained as a function of depth and disturbance of the soil surface. In support of this study, various types of soils were characterized for scattering loss across the mmW/FIR region, with measured results compared to theory. This mmW imaging system was also used to demonstrate imaging through walls and other obscuring materials, as well as for imaging of rocks beneath volcanic sand, simulating the conditions encountered by an imaging system on a Mars rover vehicle. Furthermore, a high-reflectivity Si-etalon FIR mirror design was developed and demonstrated as a cavity mirror for the p-Ge laser. These components stand to have a number of systems-level impacts on FIR imagers. In the context of an active illuminator, they may allow narrowband selection from the broad emission spectrum of the p-Ge laser source. These mirrors can also be used in a Fabry-Perot FIR scanning spectrometer, where the resulting high finesse would give discrimination advantages in chemical sensing and astrophysical spectroscopy applications

    The Third International Symposium on Space Terahertz Technology: Symposium proceedings

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    Papers from the symposium are presented that are relevant to the generation, detection, and use of the terahertz spectral region for space astronomy and remote sensing of the Earth's upper atmosphere. The program included thirteen sessions covering a wide variety of topics including solid-state oscillators, power-combining techniques, mixers, harmonic multipliers, antennas and antenna arrays, submillimeter receivers, and measurement techniques

    Topics in the optimization of millimeter-wave mixers

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    A user oriented computer program for the analysis of single-ended Schottky diode mixers is described. The program is used to compute the performance of a 140 to 220 GHz mixer and excellent agreement with measurements at 150 and 180 GHz is obtained. A sensitivity analysis indicates the importance of various diode and mount characteristics on the mixer performance. A computer program for the analysis of varactor diode multipliers is described. The diode operates in either the reverse biased varactor mode or with substantial forward current flow where the conversion mechanism is predominantly resistive. A description and analysis of a new H-plane rectangular waveguide transformer is reported. The transformer is made quickly and easily in split-block waveguide using a standard slitting saw. It is particularly suited for use in the millimeter-wave band, replacing conventional electroformed stepped transformers. A theoretical analysis of the transformer is given and good agreement is obtained with measurements made at X-band
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