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Xiaojin Zhao - One of the best experts on this subject based on the ideXlab platform.

  • Two-Step Single Slope/SAR ADC with Error Correction for CMOS Image Sensor
    TheScientificWorldJournal, 2014
    Co-Authors: Fang Tang, Amine Bermak, Abbes Amira, Mohieddine Benammar, Xiaojin Zhao
    Abstract:

    Conventional two-step ADC for CMOS image sensor requires full Resolution Noise performance in the first stage single slope ADC, leading to high power consumption and large chip area. This paper presents an 11-bit two-step single slope/successive approximation register (SAR) ADC scheme for CMOS image sensor applications. The first stage single slope ADC generates a 3-bit data and 1 redundant bit. The redundant bit is combined with the following 8-bit SAR ADC output code using a proposed error correction algorithm. Instead of requiring full Resolution Noise performance, the first stage single slope circuit of the proposed ADC can tolerate up to 3.125% quantization Noise. With the proposed error correction mechanism, the power consumption and chip area of the single slope ADC are significantly reduced. The prototype ADC is fabricated using 0.18 μm CMOS technology. The chip area of the proposed ADC is 7 μm × 500 μm. The measurement results show that the energy efficiency figure-of-merit (FOM) of the proposed ADC core is only 125 pJ/sample under 1.4 V power supply and the chip area efficiency is 84 k μm2·cycles/sample.

  • MWSCAS - Single slope/SAR column-parallel ADC with mixed-signal error correction
    2013 IEEE 56th International Midwest Symposium on Circuits and Systems (MWSCAS), 2013
    Co-Authors: Fang Tang, Yuan Cao, Xiaojin Zhao
    Abstract:

    Conventional two steps ADC for CMOS image sensor requires full Resolution Noise performance in the first stage single slope ADC, leading to high power consumption and large chip area. This paper presents a 11-bit two steps single slope/successive approximation register (SAR) ADC scheme for CMOS image sensor applications. The first stage single slope ADC generates a 3-bit data and 1 redundant bit. The redundant bit is combined with the following 8-bit SAR ADC output code using a proposed error correction algorithm. Instead of requiring full Resolution Noise performance, the first stage single slope circuit of the proposed ADC can tolerate up to 3.125% quantization Noise. With the proposed error correction mechanism, the power consumption and chip area of the single slope ADC are significantly reduced. The prototype ADC is fabricated using 0.18 μm CMOS technology. The chip area of the proposed ADC is 7 μm × 500 μm The measurement results show that the energy efficiency figure-of-merit (FOM) of the proposed ADC core is only 125 pJ/sample under 1.4 V power supply and the chip area efficiency is 84k μm2.cycles/sample.

V. P. Palamarchuk - One of the best experts on this subject based on the ideXlab platform.

  • High Resolution Noise Radar without Fast ADC
    International Journal of Electronics and Telecommunications, 2012
    Co-Authors: Konstantin Lukin, Pavlo Vyplavin, Oleg Zemlyaniy, V. P. Palamarchuk, Sergii K. Lukin
    Abstract:

    High Resolution Noise Radar without Fast ADCConventional digital signal processing scheme in Noise radars has certain limitations related to combination of high Resolution and high dynamic range. The bandwidth of radar signal defines range Resolution of any radar: the wider the spectrum the better the Resolution. In Noise radar with conventional processing the sounding and reference signals are to be digitized at intermediate frequency band and to be processed digitally. The power spectrum bandwidth of Noise signal which can be digitized with ADC depends on its sampling rate. In currently available ADCs the faster is sampling rate the smaller is its depth (number of bits). Depth of the ADC determines relation between the smallest and highest observable signals and thus limits its dynamic range. Actually this is the main bottleneck of high Resolution Noise Radars: conventional processing does not enable getting high range Resolution and high dynamic range at the same time. In the paper we discuss ways to go around this drawback by changing signal processing ideology in Noise radar. We present results of our consideration and design of two types of high Resolution Noise Radar which uses slow ADCs: Noise radar with digital generation of sounding signal and analog evaluation of cross-correlation and stepped frequency Noise radar. We describe main ideas of these radar schemes and results of experimental tests of the approaches.

  • High-Resolution Noise radar using slow ADC
    Radar Sensor Technology XV, 2011
    Co-Authors: Konstantin Lukin, Pavlo Vyplavin, Oleg Zemlyanyi, S. Lukin, V. P. Palamarchuk
    Abstract:

    Conventional digital signal processing scheme in Noise radars has some limitations related to combination of high Resolution and high dynamic range. Those limitations are caused by a tradeoff in performance of currently available ADCs: the faster is ADC the smaller is its depth (number of bits) available. Depth of the ADC determines relation between the smallest and highest observable signals and thus limits its dynamic range. In Noise radar with conventional processing the sounding and reference signals are to be digitized at intermediate frequency band and to be processed digitally. The power spectrum bandwidth of Noise signal which can be digitized with ADC depends on its sampling rate. The bandwidth of radar signal defines range Resolution of any radar: the wider the spectrum the better the Resolution. Actually this is the main bottleneck of high Resolution Noise Radars: conventional processing doesn't enable to get both high range Resolution and high dynamic range. In the paper we present a way to go around this drawback by changing signal processing ideology in Noise radar. We present results of our consideration and design of high Resolution Noise Radar which uses slow ADCs. The design is based upon generation of both probing and reference signals digitally and realization of their cross-correlation in an analog correlator. The output of the correlator is a narrowband signal that requires rather slow ADC to be sampled which nowadays may give up to 130 dB dynamic range.

  • High Resolution and high dynamic range Noise radar
    2011 MICROWAVES RADAR AND REMOTE SENSING SYMPOSIUM, 2011
    Co-Authors: Konstantin Lukin, Pavlo Vyplavin, Oleg Zemlyaniy, Sergii K. Lukin, V. P. Palamarchuk
    Abstract:

    Conventional digital signal processing scheme in Noise radars has certain limitations related to combination of high Resolution and high dynamic range. The bandwidth of radar signal defines range Resolution of any radar: the wider the spectrum the better the Resolution. In Noise radar with conventional processing the sounding and reference signals are to be digitized at intermediate frequency band and to be processed digitally. The power spectrum bandwidth of Noise signal which can be digitized with ADC depends on its sampling rate. In currently available ADCs the faster is sampling rate the smaller is its depth (number of bits) available. Depth of the ADC determines relation between the smallest and highest observable signals and thus limits its dynamic range. Actually this is the main bottleneck of high Resolution Noise Radars: conventional processing doesn't enable getting high range Resolution and high dynamic range. In the paper we discuss ways to go around this drawback by changing signal processing ideology in Noise radar. We present results of our consideration and design of two types of high Resolution Noise Radar which uses slow ADCs: Noise radar with digital generation of sounding signal and analog evaluation of cross-correlation and stepped frequency Noise radar. We describe main ideas of these radar schemes and results of experimental tests of the approaches

G. Hildebrandt - One of the best experts on this subject based on the ideXlab platform.

  • Current Resolution, Noise, and inductance measurements on high‐Tc dc SQUID galvanometers
    Applied Physics Letters, 1996
    Co-Authors: Evgeni Il'ichev, L. Dörrer, Frank Schmidl, V. Zakosarenko, Paul Seidel, G. Hildebrandt
    Abstract:

    Single layer autonomous high‐Tc dc superconducting quantum interference devices (SQUIDs) have been fabricated and tested. The SQUIDs were designed for application as a galvanometer. The current to be measured is injected directly in a microstrip segment of the SQUID loop. Step‐edge as well as bicrystal YBCO Josephson junctions were used. We consider two aspects: (i) optimization of the Noise properties with respect to current Resolution, and (ii) temperature dependence of the period of voltage‐flux relation. The SQUID inductance was calculated numerically taking into account the magnetic field penetration depth λ. The temperature dependence of λ(T) was obtained from experimental results and is found to be in good agreement with λ(T)≊λ(0)[1−(T/TC)2]−1/2.

Konstantin Lukin - One of the best experts on this subject based on the ideXlab platform.

  • High Resolution Noise Radar without Fast ADC
    International Journal of Electronics and Telecommunications, 2012
    Co-Authors: Konstantin Lukin, Pavlo Vyplavin, Oleg Zemlyaniy, V. P. Palamarchuk, Sergii K. Lukin
    Abstract:

    High Resolution Noise Radar without Fast ADCConventional digital signal processing scheme in Noise radars has certain limitations related to combination of high Resolution and high dynamic range. The bandwidth of radar signal defines range Resolution of any radar: the wider the spectrum the better the Resolution. In Noise radar with conventional processing the sounding and reference signals are to be digitized at intermediate frequency band and to be processed digitally. The power spectrum bandwidth of Noise signal which can be digitized with ADC depends on its sampling rate. In currently available ADCs the faster is sampling rate the smaller is its depth (number of bits). Depth of the ADC determines relation between the smallest and highest observable signals and thus limits its dynamic range. Actually this is the main bottleneck of high Resolution Noise Radars: conventional processing does not enable getting high range Resolution and high dynamic range at the same time. In the paper we discuss ways to go around this drawback by changing signal processing ideology in Noise radar. We present results of our consideration and design of two types of high Resolution Noise Radar which uses slow ADCs: Noise radar with digital generation of sounding signal and analog evaluation of cross-correlation and stepped frequency Noise radar. We describe main ideas of these radar schemes and results of experimental tests of the approaches.

  • High-Resolution Noise radar using slow ADC
    Radar Sensor Technology XV, 2011
    Co-Authors: Konstantin Lukin, Pavlo Vyplavin, Oleg Zemlyanyi, S. Lukin, V. P. Palamarchuk
    Abstract:

    Conventional digital signal processing scheme in Noise radars has some limitations related to combination of high Resolution and high dynamic range. Those limitations are caused by a tradeoff in performance of currently available ADCs: the faster is ADC the smaller is its depth (number of bits) available. Depth of the ADC determines relation between the smallest and highest observable signals and thus limits its dynamic range. In Noise radar with conventional processing the sounding and reference signals are to be digitized at intermediate frequency band and to be processed digitally. The power spectrum bandwidth of Noise signal which can be digitized with ADC depends on its sampling rate. The bandwidth of radar signal defines range Resolution of any radar: the wider the spectrum the better the Resolution. Actually this is the main bottleneck of high Resolution Noise Radars: conventional processing doesn't enable to get both high range Resolution and high dynamic range. In the paper we present a way to go around this drawback by changing signal processing ideology in Noise radar. We present results of our consideration and design of high Resolution Noise Radar which uses slow ADCs. The design is based upon generation of both probing and reference signals digitally and realization of their cross-correlation in an analog correlator. The output of the correlator is a narrowband signal that requires rather slow ADC to be sampled which nowadays may give up to 130 dB dynamic range.

  • High Resolution and high dynamic range Noise radar
    2011 MICROWAVES RADAR AND REMOTE SENSING SYMPOSIUM, 2011
    Co-Authors: Konstantin Lukin, Pavlo Vyplavin, Oleg Zemlyaniy, Sergii K. Lukin, V. P. Palamarchuk
    Abstract:

    Conventional digital signal processing scheme in Noise radars has certain limitations related to combination of high Resolution and high dynamic range. The bandwidth of radar signal defines range Resolution of any radar: the wider the spectrum the better the Resolution. In Noise radar with conventional processing the sounding and reference signals are to be digitized at intermediate frequency band and to be processed digitally. The power spectrum bandwidth of Noise signal which can be digitized with ADC depends on its sampling rate. In currently available ADCs the faster is sampling rate the smaller is its depth (number of bits) available. Depth of the ADC determines relation between the smallest and highest observable signals and thus limits its dynamic range. Actually this is the main bottleneck of high Resolution Noise Radars: conventional processing doesn't enable getting high range Resolution and high dynamic range. In the paper we discuss ways to go around this drawback by changing signal processing ideology in Noise radar. We present results of our consideration and design of two types of high Resolution Noise Radar which uses slow ADCs: Noise radar with digital generation of sounding signal and analog evaluation of cross-correlation and stepped frequency Noise radar. We describe main ideas of these radar schemes and results of experimental tests of the approaches

G N Rao - One of the best experts on this subject based on the ideXlab platform.

  • Performance-Enhanced Bolometric Terahertz Detectors Based on V_2O_5 for 15 to 30 THz
    Journal of Infrared Millimeter and Terahertz Waves, 2017
    Co-Authors: M. A. Sumesh, Beno Thomas, Sandeep P Karanth, G.m. Rao, P. Chakraborty, M Viswanathan, G N Rao
    Abstract:

    Terahertz (THz) radiation perception using uncooled detectors are gaining importance due to the increasing demands in the areas of military, space, and industrial, medical, and surveillance applications. In spite of the efforts of researchers to fill the THz gap, there exists a need for detectors in the range between 15 THz and 30 THz. In this paper, we discuss the development of bolometric detectors whose performance is enhanced by an optical immersion technique and their characterization in the aforesaid range of frequencies. These detectors are characterized by high specific detectivity ( D *) of 1.28 × 10^9 cmHz^1/2 W^−1 and high radiometric Resolution (Noise-equivalent temperature difference = 26 mK) and are fast enough for bolometric detectors (time constant = 1.7 ms), which make them suitable for spectroscopic and imaging applications.

  • Performance-Enhanced Bolometric Terahertz Detectors Based on V2O5 for 15 to 30 THz
    Journal of Infrared Millimeter and Terahertz Waves, 2016
    Co-Authors: M. A. Sumesh, Beno Thomas, Sandeep P Karanth, G.m. Rao, P. Chakraborty, M Viswanathan, G N Rao
    Abstract:

    Terahertz (THz) radiation perception using uncooled detectors are gaining importance due to the increasing demands in the areas of military, space, and industrial, medical, and surveillance applications. In spite of the efforts of researchers to fill the THz gap, there exists a need for detectors in the range between 15 THz and 30 THz. In this paper, we discuss the development of bolometric detectors whose performance is enhanced by an optical immersion technique and their characterization in the aforesaid range of frequencies. These detectors are characterized by high specific detectivity (D*) of 1.28 × 109 cmHz1/2 W−1 and high radiometric Resolution (Noise-equivalent temperature difference = 26 mK) and are fast enough for bolometric detectors (time constant = 1.7 ms), which make them suitable for spectroscopic and imaging applications.