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Imran Mehdi - One of the best experts on this subject based on the ideXlab platform.

  • a Frequency multiplied source with more than 1 mw of power across the 840 900 ghz band
    IEEE Transactions on Microwave Theory and Techniques, 2010
    Co-Authors: A Maestrini, John Ward, Goutam Chattopadhyay, Robert Lin, J Gill, Choonsup Lee, Bertrand Thomas, Imran Mehdi
    Abstract:

    We report on the design, fabrication, and characterization of an 840-900-GHz Frequency Multiplier chain that delivers more than 1 mW across the band at room temperature with a record peak power of 1.4 mW at 875 GHz. When cooled to 120 K, the chain delivers up to 2 mW at 882 GHz. The chain consists of a power amplifier module that drives two cascaded Frequency triplers. This unprecedented output power from an electronic source is achieved by utilizing in-phase power-combining techniques. The first stage tripler uses four power-combined chips while the last stage tripler utilizes two power-combined chips. The source output was analyzed with a Fourrer transform spectrometer to verify signal purity.

  • a 260 340 ghz dual chip Frequency tripler for thz Frequency Multiplier chains
    Joint International Conference on Infrared Millimeter Waves and International Conference on Teraherz Electronics, 2006
    Co-Authors: A Maestrini, J Gill, C Triponcanseliet, J S Wardw, Imran Mehdi
    Abstract:

    We designed and fabricated a fix-tuned balanced Frequency tripler working in the 260-340 GHz band to be the first stage of a times3times3times3 Multiplier chain to 2.7 THz. The design of a dual-chip version of this Multiplier featuring an input splitter/output combiner as part of the input/output matching networks of both chips - with no degradation of the expected bandwidth and efficiency- will be presented.

  • local oscillator chain for 1 55 to 1 75thz with 100 spl mu w peak power
    IEEE Microwave and Wireless Components Letters, 2005
    Co-Authors: A Maestrini, John Ward, Erich Schlecht, Goutam Chattopadhyay, J Gill, H Javadi, C Triponcanseliet, Imran Mehdi
    Abstract:

    We report on the design and performance of a fix-tuned /spl times/2/spl times/3/spl times/3 Frequency Multiplier chain that covers 1.55-1.75THz. The chain is nominally pumped with 100mW at W-band. At 120K the measured output power is larger than 4/spl mu/W across the band with a peak power of 100/spl mu/W at 1.665THz. A similar chain operated at room temperature produced a peak power of 21/spl mu/W. These power levels now make it possible to deploy multipixel heterodyne imaging arrays in this Frequency range.

  • capability of thz sources based on schottky diode Frequency Multiplier chains
    International Microwave Symposium, 2004
    Co-Authors: John Ward, Erich Schlecht, Goutam Chattopadhyay, Alain Maestrini, John Gill, Frank Maiwald, Hamid Javadi, Imran Mehdi
    Abstract:

    We have developed and tested a number of fixed-tuned GaAs Schottky diode Frequency doubler and tripler designs covering over 50% of the 100 - 2000 GHz band, with best measured 120 K peak efficiencies ranging from 39% for a 190 GHz doubler to 0.94% for 1800 GHz tripler. We find that the efficiencies across this broad range of Frequency and performance can be well-described by a simple empirical exponential decay model. This model can be used to predict achievable performance for Schottky diode Frequency Multipliers and Multiplier chains, and gives an indication of what chain configurations are most likely to produce optimal results to reach a given Frequency range. Extrapolating the models beyond the highest frequencies tested predicts that cooled Schottky diode Frequency Multiplier chains are capable of producing at least 1 /spl mu/W at 2.5 THz.

  • an all solid state broad band Frequency Multiplier chain at 1500 ghz
    IEEE Transactions on Microwave Theory and Techniques, 2004
    Co-Authors: Goutam Chattopadhyay, John Ward, Erich Schlecht, J Gill, H Javadi, F Maiwald, Imran Mehdi
    Abstract:

    We report the results of a high-performance all-solid-state broad-band Frequency Multiplier chain at 1500 GHz, which uses four cascaded planar Schottky-barrier varactor doublers. The Multipliers are driven by monolithic-microwave integrated-circuit-based high electron-mobility transistor power amplifiers around 95 GHz with 100-150 mW of pump power. The design incorporates balanced doublers utilizing novel substrateless and membrane device fabrication technologies, achieving low-loss broad-band Multipliers working in the terahertz range. For a drive power of approximately 100 mW in the 88-99-GHz range, the doublers achieved room-temperature peak efficiencies of approximately 30% at the 190-GHz stage, 20% at 375 GHz, 9% at 750 GHz, and 4% at the 1500-GHz stage. When the chain was cooled to 120 K, approximately 40 /spl mu/W of peak output power was measured for 100 mW of input pump power.

Yubin Gong - One of the best experts on this subject based on the ideXlab platform.

  • generation of high power tunable terahertz radiation by nonrelativistic beam echo harmonic effect
    Physics of Plasmas, 2013
    Co-Authors: Huarong Gong, G Travish, Yanyu Wei, Jinjun Feng, Yubin Gong
    Abstract:

    A new type of terahertz radiation source based on the nonrelativistic electron beam-wave interaction is proposed. Here, the beam echo harmonic effect is applied to a traveling wave tube like device. The scheme is configured as a combination of a Frequency Multiplier and amplifier with, for instance, W-band (millimeter wave) input signals and terahertz output power. A one-dimensional model of this device shows that a 10th order harmonic-wave can be generated while other harmonic waves are suppressed. The device only requires a readily available input source (W-band), and the output Frequency can be tuned continuously over a wide band.

  • high power tunable terahertz radiation by high order harmonic generation
    IEEE Transactions on Electron Devices, 2013
    Co-Authors: Huarong Gong, G Travish, Yanyu Wei, Jinjun Feng, Yubin Gong
    Abstract:

    We propose a new type of terahertz (THz) radiation source based on the electron beam-wave interaction. A high-order harmonic-generation process was introduced to a traveling-wave tube (TWT)-like device-the high-harmonic TWT or HHTWT. The scheme is configured as a Frequency Multiplier and amplifier with W-band (millimeter wave) input signals and THz output power. Simulations show that operation at the seventh harmonic is possible and other order harmonic waves were suppressed. The output Frequency can be tuned continuously over a 30-GHz bandwidth with more than 20-dBm output power. The peak output power is about 30 dBm at 707 GHz. The output Frequency is insensitive to beam voltage jitter.

A Leuther - One of the best experts on this subject based on the ideXlab platform.

  • Frequency Multiplier and mixer mmics based on a metamorphic hemt technology including schottky diodes
    IEEE Access, 2020
    Co-Authors: Fabian Thome, A Leuther, Erdin Ture, Robert Iannucci, F Schafer, A Navarrini, Patrice Serres
    Abstract:

    This paper reports on the monolithic integration of layout-optimized Schottky diodes realized in an established 50-nm gate-length metamorphic high-electron-mobility transistor technology for use in multifunctional nonlinear circuits. The suitability of the realized Schottky diodes is demonstrated by a broadband millimeter-wave I/Q-mixer (In-phase/Quadrature) and local oscillator (LO) chain comprising two power amplifiers and a Frequency tripler, fabricated on monolithic microwave integrated circuits (MMICs). Both circuits are based on an anti-parallel Schottky diode topology. The subharmonically-pumped I/Q-mixer covers an RF (radio Frequency) and IF (intermediate Frequency) range of at least 75 GHz to 110 GHz and 0.5 GHz to 15 GHz, respectively. The single-sideband conversion loss is between 14 dB and 16 dB across most of the entire RF and IF bands. The core of the LO chain consists of a Frequency tripler (Multiplier by three) and features a bias-adjustable output power with almost constant conversion efficiency and a control range of more than 8 dB. The fully-integrated LO chain MMIC matches the needs of the presented I/Q-mixer and exhibits an average output power of 16.3 dBm with a covered Frequency range of 38 GHz to 60 GHz. The unwanted harmonics are suppressed by at least −25.9 dBc below the third harmonic for the entire Frequency range and better than −32.1 dBc for most part of the band. Thus, the mixer and tripler MMICs demonstrate state-of-the-art performance with regards to, e.g., covered bandwidth, output power, harmonic suppression, or 1 dB compression point.

  • an active 600 ghz Frequency Multiplier by six s mmic
    International Microwave Symposium, 2013
    Co-Authors: U J Lewark, A Tessmann, H Massler, A Leuther, Thomas Zwick, I Kallfass
    Abstract:

    For submillimeter-wave generation we present an active six-fold Frequency Multiplier circuit operating with an average output power of -16 dBm without post amplification and a measured output Frequency range from 580 to 625 GHz. The S-MMIC is realized in a metamorphic HEMT technology with 35 nm gate-length for convenient multifunctional circuit integration.

  • e band active Frequency Multiplier by eight mmic with 20 db conversion gain and excellent spurious suppression
    International Microwave Symposium, 2012
    Co-Authors: U J Lewark, A Tessmann, H Massler, A Leuther, I Kallfass
    Abstract:

    We present an active eight-fold Frequency-Multiplier with more than 20 dB conversion gain. The output 3-dB bandwidth is 72 to 85GHz, forming a tunable Frequency source within the 71 to 76 and 81 to 86GHz communication bands with a saturated output power of 10 dBm for LO generation with an input power of only −8 dBm. The suppression of unwanted harmonics is better than 37 dBc. The MMIC is realized in a metamorphic HEMT technology with 100 nm gate-length.

  • a w band x12 Frequency Multiplier mmic in waveguide package using quartz and ceramic transitions
    Compound Semiconductor Integrated Circuit Symposium, 2011
    Co-Authors: Rainer Weber, A Tessmann, H Massler, I Kallfass, M Zink, M Kuri, H P Stulz, M Riessle, T Maier, A Leuther
    Abstract:

    This paper describes a single-chip W-band Frequency Multiplier MMIC in a waveguide package. The multiplication factor by 12 has been obtained with a doubler, tripler and doubler chain. The MMIC has been realized in a 100 nm metamorphic HEMT technology. It has been packaged in a split-block module using a high precision 50 µm thick quartz transition for the W-band output and a low cost ceramic transition on the input. A power supply board, embedded in the module, provides six different voltages to the MMIC. The packaged Frequency Multiplier achieves an output power of -0.8 dBm, a conversion gain of 0.2 dB and a 3-dB bandwidth of 16 GHz from 86 to 102 GHz with a suppression of the unwanted harmonics of more than 25.5 dBc. The phase-noise of the output signal is not affected by the Multiplier circuit.

  • active single ended Frequency Multiplier by nine mmic for millimeter wave imaging applications
    Workshop on Integrated Nonlinear Microwave and Millimetre-wave Circuits, 2011
    Co-Authors: U J Lewark, A Tessmann, H Massler, A Leuther, I Kallfass
    Abstract:

    An active Frequency Multiplier-by-nine MMIC with integrated buffer amplifier reaching 94 GHz from X-band is presented. The Multiplier-by-nine generates an average output power of −7.7 dBm in the Frequency range from 82 to 102 GHz. At 94 GHz the measured output power is −6.4 dBm with an input power of 10 dBm. The suppression of unwanted harmonics is better than 23 dBc. The comparison to the simulated results shows the performance of the underlying large-signal mHEMT models. The MMIC is realized in metamorphic HEMT technology with 100 nm gate-length.

I Kallfass - One of the best experts on this subject based on the ideXlab platform.

  • an active 600 ghz Frequency Multiplier by six s mmic
    International Microwave Symposium, 2013
    Co-Authors: U J Lewark, A Tessmann, H Massler, A Leuther, Thomas Zwick, I Kallfass
    Abstract:

    For submillimeter-wave generation we present an active six-fold Frequency Multiplier circuit operating with an average output power of -16 dBm without post amplification and a measured output Frequency range from 580 to 625 GHz. The S-MMIC is realized in a metamorphic HEMT technology with 35 nm gate-length for convenient multifunctional circuit integration.

  • e band active Frequency Multiplier by eight mmic with 20 db conversion gain and excellent spurious suppression
    International Microwave Symposium, 2012
    Co-Authors: U J Lewark, A Tessmann, H Massler, A Leuther, I Kallfass
    Abstract:

    We present an active eight-fold Frequency-Multiplier with more than 20 dB conversion gain. The output 3-dB bandwidth is 72 to 85GHz, forming a tunable Frequency source within the 71 to 76 and 81 to 86GHz communication bands with a saturated output power of 10 dBm for LO generation with an input power of only −8 dBm. The suppression of unwanted harmonics is better than 37 dBc. The MMIC is realized in a metamorphic HEMT technology with 100 nm gate-length.

  • a w band x12 Frequency Multiplier mmic in waveguide package using quartz and ceramic transitions
    Compound Semiconductor Integrated Circuit Symposium, 2011
    Co-Authors: Rainer Weber, A Tessmann, H Massler, I Kallfass, M Zink, M Kuri, H P Stulz, M Riessle, T Maier, A Leuther
    Abstract:

    This paper describes a single-chip W-band Frequency Multiplier MMIC in a waveguide package. The multiplication factor by 12 has been obtained with a doubler, tripler and doubler chain. The MMIC has been realized in a 100 nm metamorphic HEMT technology. It has been packaged in a split-block module using a high precision 50 µm thick quartz transition for the W-band output and a low cost ceramic transition on the input. A power supply board, embedded in the module, provides six different voltages to the MMIC. The packaged Frequency Multiplier achieves an output power of -0.8 dBm, a conversion gain of 0.2 dB and a 3-dB bandwidth of 16 GHz from 86 to 102 GHz with a suppression of the unwanted harmonics of more than 25.5 dBc. The phase-noise of the output signal is not affected by the Multiplier circuit.

  • active single ended Frequency Multiplier by nine mmic for millimeter wave imaging applications
    Workshop on Integrated Nonlinear Microwave and Millimetre-wave Circuits, 2011
    Co-Authors: U J Lewark, A Tessmann, H Massler, A Leuther, I Kallfass
    Abstract:

    An active Frequency Multiplier-by-nine MMIC with integrated buffer amplifier reaching 94 GHz from X-band is presented. The Multiplier-by-nine generates an average output power of −7.7 dBm in the Frequency range from 82 to 102 GHz. At 94 GHz the measured output power is −6.4 dBm with an input power of 10 dBm. The suppression of unwanted harmonics is better than 23 dBc. The comparison to the simulated results shows the performance of the underlying large-signal mHEMT models. The MMIC is realized in metamorphic HEMT technology with 100 nm gate-length.

  • a w band active Frequency Multiplier by six in waveguide package
    German Microwave Conference, 2010
    Co-Authors: I Kallfass, A Tessmann, H Massler, M Zink, M Kuri, M Riessle, A Leuther
    Abstract:

    We demonstrate a broadband active Frequency-Multiplier-by-six for the W-band (75–110GHz), mounted in a waveguide package. The Frequency-multiplying function is performed in a single MMIC using a cascade of balanced tripler and doubler stages. The MMIC, realized in metamorphic HEMT technology, is mounted by wire bonding and high performance waveguide-to-microstrip transitions into a split-block waveguide module containing an integrated voltage supply board. The module achieves an output power of 2.5dBm, with an associated conversion gain of 0.5 dB, and a 3-dB output bandwidth of 21.5%, corresponding to a Frequency range from 83 to 103 GHz. Unwanted harmonics in the output spectrum are suppressed by more than 18dB. The application of the employed packaging technique to frequencies up to 325GHz is discussed.

Huarong Gong - One of the best experts on this subject based on the ideXlab platform.

  • generation of high power tunable terahertz radiation by nonrelativistic beam echo harmonic effect
    Physics of Plasmas, 2013
    Co-Authors: Huarong Gong, G Travish, Yanyu Wei, Jinjun Feng, Yubin Gong
    Abstract:

    A new type of terahertz radiation source based on the nonrelativistic electron beam-wave interaction is proposed. Here, the beam echo harmonic effect is applied to a traveling wave tube like device. The scheme is configured as a combination of a Frequency Multiplier and amplifier with, for instance, W-band (millimeter wave) input signals and terahertz output power. A one-dimensional model of this device shows that a 10th order harmonic-wave can be generated while other harmonic waves are suppressed. The device only requires a readily available input source (W-band), and the output Frequency can be tuned continuously over a wide band.

  • high power tunable terahertz radiation by high order harmonic generation
    IEEE Transactions on Electron Devices, 2013
    Co-Authors: Huarong Gong, G Travish, Yanyu Wei, Jinjun Feng, Yubin Gong
    Abstract:

    We propose a new type of terahertz (THz) radiation source based on the electron beam-wave interaction. A high-order harmonic-generation process was introduced to a traveling-wave tube (TWT)-like device-the high-harmonic TWT or HHTWT. The scheme is configured as a Frequency Multiplier and amplifier with W-band (millimeter wave) input signals and THz output power. Simulations show that operation at the seventh harmonic is possible and other order harmonic waves were suppressed. The output Frequency can be tuned continuously over a 30-GHz bandwidth with more than 20-dBm output power. The peak output power is about 30 dBm at 707 GHz. The output Frequency is insensitive to beam voltage jitter.