The Experts below are selected from a list of 59388 Experts worldwide ranked by ideXlab platform
Yeshaiahu Fainman - One of the best experts on this subject based on the ideXlab platform.
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demonstration of a microwave spectrum analyzer based on Time Domain optical Processing in fiber
Optics Letters, 2004Co-Authors: R E Saperstein, Dmitriy Panasenko, Yeshaiahu FainmanAbstract:We demonstrate a novel method for spectral analysis of microwave signals that employs Time-Domain Processing in fiber. We use anomalous dispersion in single-mode fiber to perform a Fresnel transform followed by a matched amount of dispersion-compensating fiber to perform an inverse Fresnel transform of an ultrashort pulse. After the Fresnel-transformed waveform is modulated by the microwave signal, the waveform at the output of the dispersion-compensating fiber represents the ultrashort pulse convolved with the microwave spectrum. An experimental system for spectral analysis of microwave signals in the range 6-21 GHz is demonstrated.
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demonstration of a microwave spectrum analyzer using Time Domain Processing in optical fibers
Lasers and Electro-Optics Society Meeting, 2003Co-Authors: R E Saperstein, Dmitriy Panasenko, Yeshaiahu FainmanAbstract:In this paper we demonstrate a novel method of direct, frequency Domain, spectrum analysis relying on the manipulation of microwave-modulated optical pulses using chromatic dispersion. In our approach the utility of dispersion for signal Processing is extended when fiber of opposite dispersion sign and appropriate length is added to a preceding link to perform an inverse Fourier transform (IFT).
Motoyuki Sato - One of the best experts on this subject based on the ideXlab platform.
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Direct path interference suppression for short-range passive bistatic synthetic aperture radar imaging based on atomic norm minimisation and Vandermonde decomposition
IET Radar Sonar & Navigation, 2019Co-Authors: Weike Feng, Jean Friedt, Grigory Cherniak, Motoyuki SatoAbstract:A novel direct path interference (DPI) suppression method is proposed for passive bistatic synthetic aperture radar (SAR) imaging applications. Conventional Time-Domain Processing methods cannot mitigate the DPI completely and will introduce errors into the target position estimation. By exploiting the sparsity of the DPI signal and the properties of its covariance matrix, the proposed method solves these problems by accurately estimating the Time delay of DPI based on the atomic minimisation algorithm and Vandermonde decomposition in the frequency Domain. The amplitude of DPI is then calculated by the least squares method. Simulations and experimental results of Wireless Fidelity-based passive bistatic SAR imaging of short-range targets show that the proposed method can suppress DPI more effectively and estimate the position of the target more accurately than the classical method.
Sato Motoyuki - One of the best experts on this subject based on the ideXlab platform.
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Direct path interference suppression for short-range passive bistatic synthetic aperture radar imaging based on atomic norm minimisation and Vandermonde decomposition
HAL CCSD, 2019Co-Authors: Feng Weike, Friedt Jean, Cherniak Grigory, Hu Zhipeng, Sato MotoyukiAbstract:International audienceA novel direct path interference (DPI) suppression method is proposed for passive bistatic synthetic aperture radar (SAR) imaging applications. Conventional Time-Domain Processing methods cannot mitigate the DPI completely and will introduce errors into the target position estimation. By exploiting the sparsity of the DPI signal and the properties of its covariance matrix, the proposed method solves these problems by accurately estimating the Time delay of DPI based on the atomic minimisation algorithm and Vandermonde decomposition in the frequency Domain. The amplitude of DPI is then calculated by the least squares method. Simulations and experimental results of Wireless Fidelity-based passive bistatic SAR imaging of short-range targets show that the proposed method can suppress DPI more effectively and estimate the position of the target more accurately than the classical method
R E Saperstein - One of the best experts on this subject based on the ideXlab platform.
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demonstration of a microwave spectrum analyzer based on Time Domain optical Processing in fiber
Optics Letters, 2004Co-Authors: R E Saperstein, Dmitriy Panasenko, Yeshaiahu FainmanAbstract:We demonstrate a novel method for spectral analysis of microwave signals that employs Time-Domain Processing in fiber. We use anomalous dispersion in single-mode fiber to perform a Fresnel transform followed by a matched amount of dispersion-compensating fiber to perform an inverse Fresnel transform of an ultrashort pulse. After the Fresnel-transformed waveform is modulated by the microwave signal, the waveform at the output of the dispersion-compensating fiber represents the ultrashort pulse convolved with the microwave spectrum. An experimental system for spectral analysis of microwave signals in the range 6-21 GHz is demonstrated.
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demonstration of a microwave spectrum analyzer using Time Domain Processing in optical fibers
Lasers and Electro-Optics Society Meeting, 2003Co-Authors: R E Saperstein, Dmitriy Panasenko, Yeshaiahu FainmanAbstract:In this paper we demonstrate a novel method of direct, frequency Domain, spectrum analysis relying on the manipulation of microwave-modulated optical pulses using chromatic dispersion. In our approach the utility of dispersion for signal Processing is extended when fiber of opposite dispersion sign and appropriate length is added to a preceding link to perform an inverse Fourier transform (IFT).
Akrami Y. - One of the best experts on this subject based on the ideXlab platform.
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Planck intermediate results
'EDP Sciences', 2020Co-Authors: Akrami Y., Andersen K. J., Ashdown M., Baccigalupi C., Ballardini M., Banday A. J., Barreiro R. B., Bartolo N., Basak S., Benabed K.Abstract:We present the NPIPE Processing pipeline, which produces calibrated frequency maps in temperature and polarization from data from the Planck Low Frequency Instrument (LFI) and High Frequency Instrument (HFI) using high-performance computers. NPIPE represents a natural evolution of previous Planck analysis efforts, and combines some of the most powerful features of the separate LFI and HFI analysis pipelines. For example, following the LFI 2018 Processing procedure, NPIPE uses foreground polarization priors during the calibration stage in order to break scanning-induced degeneracies. Similarly, NPIPE employs the HFI 2018 Time-Domain Processing methodology to correct for bandpass mismatch at all frequencies. In addition, NPIPE introduces several improvements, including, but not limited to: inclusion of the 8% of data collected during repointing manoeuvres; smoothing of the LFI reference load data streams; in-flight estimation of detector polarization parameters; and construction of maximally independent detector-set split maps. For component-separation purposes, important improvements include: maps that retain the CMB Solar dipole, allowing for high-precision relative calibration in higher-level analyses; well-defined single-detector maps, allowing for robust CO extraction; and HFI temperature maps between 217 and 857 GHz that are binned into 0′.9 pixels (Nside = 4096), ensuring that the full angular information in the data is represented in the maps even at the highest Planck resolutions. The net effect of these improvements is lower levels of noise and systematics in both frequency and component maps at essentially all angular scales, as well as notably improved internal consistency between the various frequency channels. Based on the NPIPE maps, we present the first estimate of the Solar dipole determined through component separation across all nine Planck frequencies. The amplitude is (3366.6 ± 2.7) μK, consistent with, albeit slightly higher than, earlier estimates. From the large-scale polarization data, we derive an updated estimate of the optical depth of reionization of τ = 0.051 ± 0.006, which appears robust with respect to data and sky cuts. There are 600 complete signal, noise and systematics simulations of the full-frequency and detector-set maps. As a Planck first, these simulations include full Time-Domain Processing of the beam-convolved CMB anisotropies. The release of NPIPE maps and simulations is accompanied with a complete suite of raw and processed Time-ordered data and the software, scripts, auxiliary data, and parameter files needed to improve further on the analysis and to run matching simulations.Peer reviewe
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Planck intermediate results. LVII. Joint Planck LFI and HFI data Processing
'EDP Sciences', 2020Co-Authors: Akrami Y., Andersen K. J., Ashdown M., Baccigalupi C., Ballardini M., Banday A. J., Barreiro R. B., Bartolo N., Basak S., Benabed K.Abstract:We present the NPIPE Processing pipeline, which produces calibrated frequency maps in temperature and polarization from data from the Planck Low Frequency Instrument (LFI) and High Frequency Instrument (HFI) using high-performance computers. NPIPE represents a natural evolution of previous Planck analysis efforts, and combines some of the most powerful features of the separate LFI and HFI analysis pipelines. For example, following the LFI 2018 Processing procedure, NPIPE uses foreground polarization priors during the calibration stage in order to break scanning-induced degeneracies. Similarly, NPIPE employs the HFI 2018 Time-Domain Processing methodology to correct for bandpass mismatch at all frequencies. In addition, NPIPE introduces several improvements, including, but not limited to: inclusion of the 8% of data collected during repointing manoeuvres; smoothing of the LFI reference load data streams; in-flight estimation of detector polarization parameters; and construction of maximally independent detector-set split maps. For component-separation purposes, important improvements include: maps that retain the CMB Solar dipole, allowing for high-precision relative calibration in higher-level analyses; well-defined single-detector maps, allowing for robust CO extraction; and HFI temperature maps between 217 and 857 GHz that are binned into 0′.9 pixels (N_(side) = 4096), ensuring that the full angular information in the data is represented in the maps even at the highest Planck resolutions. The net effect of these improvements is lower levels of noise and systematics in both frequency and component maps at essentially all angular scales, as well as notably improved internal consistency between the various frequency channels. Based on the NPIPE maps, we present the first estimate of the Solar dipole determined through component separation across all nine Planck frequencies. The amplitude is (3366.6 ± 2.7) μK, consistent with, albeit slightly higher than, earlier estimates. From the large-scale polarization data, we derive an updated estimate of the optical depth of reionization of τ = 0.051 ± 0.006, which appears robust with respect to data and sky cuts. There are 600 complete signal, noise and systematics simulations of the full-frequency and detector-set maps. As a Planck first, these simulations include full Time-Domain Processing of the beam-convolved CMB anisotropies. The release of NPIPE maps and simulations is accompanied with a complete suite of raw and processed Time-ordered data and the software, scripts, auxiliary data, and parameter files needed to improve further on the analysis and to run matching simulations
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Planck intermediate results: LVII. Joint Planck LFI and HFI data Processing
'EDP Sciences', 2020Co-Authors: Akrami Y., Andersen K. J., Ashdown M., Baccigalupi C., Ballardini M., Banday A. J., Barreiro R. B., Bartolo N., Basak S., Benabed K.Abstract:International audienceWe present the NPIPE Processing pipeline, which produces calibrated frequency maps in temperature and polarization from data from the Planck Low Frequency Instrument (LFI) and High Frequency Instrument (HFI) using high-performance computers. NPIPE represents a natural evolution of previous Planck analysis efforts, and combines some of the most powerful features of the separate LFI and HFI analysis pipelines. For example, following the LFI 2018 Processing procedure, NPIPE uses foreground polarization priors during the calibration stage in order to break scanning-induced degeneracies. Similarly, NPIPE employs the HFI 2018 Time-Domain Processing methodology to correct for bandpass mismatch at all frequencies. In addition, NPIPE introduces several improvements, including, but not limited to: inclusion of the 8% of data collected during repointing manoeuvres; smoothing of the LFI reference load data streams; in-flight estimation of detector polarization parameters; and construction of maximally independent detector-set split maps. For component-separation purposes, important improvements include: maps that retain the CMB Solar dipole, allowing for high-precision relative calibration in higher-level analyses; well-defined single-detector maps, allowing for robust CO extraction; and HFI temperature maps between 217 and 857 GHz that are binned into 0′.9 pixels (Nside = 4096), ensuring that the full angular information in the data is represented in the maps even at the highest Planck resolutions. The net effect of these improvements is lower levels of noise and systematics in both frequency and component maps at essentially all angular scales, as well as notably improved internal consistency between the various frequency channels. Based on the NPIPE maps, we present the first estimate of the Solar dipole determined through component separation across all nine Planck frequencies. The amplitude is (3366.6 ± 2.7) μK, consistent with, albeit slightly higher than, earlier estimates. From the large-scale polarization data, we derive an updated estimate of the optical depth of reionization of τ = 0.051 ± 0.006, which appears robust with respect to data and sky cuts. There are 600 complete signal, noise and systematics simulations of the full-frequency and detector-set maps. As a Planck first, these simulations include full Time-Domain Processing of the beam-convolved CMB anisotropies. The release of NPIPE maps and simulations is accompanied with a complete suite of raw and processed Time-ordered data and the software, scripts, auxiliary data, and parameter files needed to improve further on the analysis and to run matching simulations
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Planck intermediate results : LVII. Joint Planck LFI and HFI data Processing
'EDP Sciences', 2020Co-Authors: Planck Collaboration, Akrami Y., Keihänen E., Kiiveri K., Kurki-suonio H., Savelainen M., Suur-uski A-s., Väliviita J.Abstract:We present the NPIPE Processing pipeline, which produces calibrated frequency maps in temperature and polarization from data from the Planck Low Frequency Instrument (LFI) and High Frequency Instrument (HFI) using high-performance computers. NPIPE represents a natural evolution of previous Planck analysis efforts, and combines some of the most powerful features of the separate LFI and HFI analysis pipelines. For example, following the LFI 2018 Processing procedure, NPIPE uses foreground polarization priors during the calibration stage in order to break scanning-induced degeneracies. Similarly, NPIPE employs the HFI 2018 Time-Domain Processing methodology to correct for bandpass mismatch at all frequencies. In addition, NPIPE introduces several improvements, including, but not limited to: inclusion of the 8% of data collected during repointing manoeuvres; smoothing of the LFI reference load data streams; in-flight estimation of detector polarization parameters; and construction of maximally independent detector-set split maps. For component-separation purposes, important improvements include: maps that retain the CMB Solar dipole, allowing for high-precision relative calibration in higher-level analyses; well-defined single-detector maps, allowing for robust CO extraction; and HFI temperature maps between 217 and 857 GHz that are binned into 0 ' .9 pixels (N-side = 4096), ensuring that the full angular information in the data is represented in the maps even at the highest Planck resolutions. The net effect of these improvements is lower levels of noise and systematics in both frequency and component maps at essentially all angular scales, as well as notably improved internal consistency between the various frequency channels. Based on the NPIPE maps, we present the first estimate of the Solar dipole determined through component separation across all nine Planck frequencies. The amplitude is (3366.6 +/- 2.7) mu K, consistent with, albeit slightly higher than, earlier estimates. From the large-scale polarization data, we derive an updated estimate of the optical depth of reionization of tau =0.051 +/- 0.006, which appears robust with respect to data and sky cuts. There are 600 complete signal, noise and systematics simulations of the full-frequency and detector-set maps. As a Planck first, these simulations include full Time-Domain Processing of the beam-convolved CMB anisotropies. The release of NPIPE maps and simulations is accompanied with a complete suite of raw and processed Time-ordered data and the software, scripts, auxiliary data, and parameter files needed to improve further on the analysis and to run matching simulations.Peer reviewe
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Planck intermediate results
'EDP Sciences', 2020Co-Authors: Akrami Y., Andersen K. J., Ashdown M., Baccigalupi C., Ballardini M., Banday A. J., Barreiro R. B., Bartolo N., Basak S., Benabed K.Abstract:We present the NPIPE Processing pipeline, which produces calibrated frequency maps in temperature and polarization from data from the Planck Low Frequency Instrument (LFI) and High Frequency Instrument (HFI) using high-performance computers. NPIPE represents a natural evolution of previous Planck analysis efforts, and combines some of the most powerful features of the separate LFI and HFI analysis pipelines. For example, following the LFI 2018 Processing procedure, NPIPE uses foreground polarization priors during the calibration stage in order to break scanning-induced degeneracies. Similarly, NPIPE employs the HFI 2018 Time-Domain Processing methodology to correct for bandpass mismatch at all frequencies. In addition, NPIPE introduces several improvements, including, but not limited to: inclusion of the 8% of data collected during repointing manoeuvres; smoothing of the LFI reference load data streams; in-flight estimation of detector polarization parameters; and construction of maximally independent detector-set split maps. For component-separation purposes, important improvements include: maps that retain the CMB Solar dipole, allowing for high-precision relative calibration in higher-level analyses; well-defined single-detector maps, allowing for robust CO extraction; and HFI temperature maps between 217 and 857 GHz that are binned into 0′.9 pixels (Nside = 4096), ensuring that the full angular information in the data is represented in the maps even at the highest Planck resolutions. The net effect of these improvements is lower levels of noise and systematics in both frequency and component maps at essentially all angular scales, as well as notably improved internal consistency between the various frequency channels. Based on the NPIPE maps, we present the first estimate of the Solar dipole determined through component separation across all nine Planck frequencies. The amplitude is (3366.6 ± 2.7) μK, consistent with, albeit slightly higher than, earlier estimates. From the large-scale polarization data, we derive an updated estimate of the optical depth of reionization of τ = 0.051 ± 0.006, which appears robust with respect to data and sky cuts. There are 600 complete signal, noise and systematics simulations of the full-frequency and detector-set maps. As a Planck first, these simulations include full Time-Domain Processing of the beam-convolved CMB anisotropies. The release of NPIPE maps and simulations is accompanied with a complete suite of raw and processed Time-ordered data and the software, scripts, auxiliary data, and parameter files needed to improve further on the analysis and to run matching simulations. Key words: cosmic background radiation / cosmology: observations / cosmological parameters / Galaxy: general / methods: data analysi
