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Fangzheng Zhang - One of the best experts on this subject based on the ideXlab platform.

  • Phase Noise Measurement of RF Signals by Photonic Time Delay and Digital Phase Demodulation
    IEEE Transactions on Microwave Theory and Techniques, 2018
    Co-Authors: Fangzheng Zhang
    Abstract:

    A simple and high-sensitivity frequency-discriminator-based phase Noise Measurement system using photonic time delay and digital phase demodulation is comprehensively investigated and experimentally demonstrated. By applying a low-loss optical fiber to provide a large amount of time delay, high phase Noise Measurement sensitivity and large operation bandwidth are guaranteed. Meanwhile, digital phase demodulation is employed to avoid sophisticated feedback control and complex calibration required in conventional frequency-discriminator-based phase Noise Measurement scheme, which not only eliminates the phase Noise Measurement error introduced by the feedback loop but also suppresses the influence of the amplitude Noise in the signal under test. In addition, a solution for the in-phase and quadrature mismatch problem in the digital phase demodulation is proposed. An experiment is performed. Accurate phase Noise Measurement is achieved in a large bandwidth from 2 to 35 GHz. With a 2-km single-mode fiber serving as the delay line, phase Noise Measurement sensitivity as low as -134 dBc/Hz at 10 kHz is achieved at a RF frequency of 10 GHz. The phase Noise sensitivity can be further improved by applying a longer fiber. The proposed system is simple, accurate, and stable, and can be applied for analysis of high-frequency and ultralow phase Noise microwave signal sources.

  • High-sensitivity phase Noise Measurement of RF sources by photonic-delay line and digital phase demodulation
    2017 16th International Conference on Optical Communications and Networks (ICOCN), 2017
    Co-Authors: Fangzheng Zhang
    Abstract:

    A high-sensitivity phase Noise Measurement scheme using photonic-delay line and digital phase demodulation is proposed, which is free of complicate calibration and amplitude Noise by using digital phase demodulation. In the experiment, a phase Noise Measurement sensitivity as high as -134 dBc/Hz@10 kHz@10 GHz is achieved applying a 2-km single mode fiber as the delay line. Besides, accurate phase Noise Measurement in a large frequency bandwidth from 2 to 35 GHz is achieved.

  • phase Noise Measurement of wideband microwave sources based on a microwave photonic frequency down converter
    Optics Letters, 2015
    Co-Authors: Fangzheng Zhang, Pei Zhou
    Abstract:

    An approach for phase Noise Measurement of microwave signal sources based on a microwave photonic frequency down-converter is proposed. Using the same optical carrier, the microwave signal under test is applied to generate two +1st-order optical sidebands by two stages of electro-optical modulations. A time delay is introduced between the two sidebands through a span of fiber. By beating the two +1st-order sidebands at a photodetector, frequency down-conversion is implemented, and phase Noise of the signal under test can be calculated thereafter. The system has a very large operation bandwidth thanks to the frequency conversion in the optical domain, and good phase Noise Measurement sensitivity can be achieved since the signal degradation caused by electrical amplifiers is avoided. An experiment is carried out. The phase Noise measured by the proposed system agrees well with that measured by a commercial spectrum analyzer or provided by the datasheet. A large operation bandwidth of 5–40 GHz is demonstrated using the proposed system. Moreover, good phase Noise floor is achieved (−123  dBc/Hz at 1 kHz and −137  dBc/Hz at 10 kHz at 10 GHz), which is nearly constant over the full Measurement range.

  • Wideband Phase Noise Measurement Using a Multifunctional Microwave Photonic Processor
    IEEE Photonics Technology Letters, 2014
    Co-Authors: Fangzheng Zhang, Pei Zhou
    Abstract:

    A novel scheme for measuring the phase Noise of microwave signal sources is proposed based on the delay-line method using a multifunctional microwave photonic processor, which can simultaneously implement the electrical-to-optical conversion, provide a time delay, and control the phase of the output microwave signal. Thanks to the microwave photonic processor, the requirement for accurate phase control is relaxed and a large operation bandwidth of the phase Noise Measurement system can be achieved. An experiment is performed. The phase Noise measured by the proposed system agrees well with the result measured by a commercial spectrum analyzer, and the Noise floor of the measuring system is lower than -130 dBc/Hz at 10 kHz frequency offset. The large operation bandwidth is also verified by measuring the phase Noise of a wideband signal source in a frequency range from 5 to 40 GHz without rebuilding the system.

Pei Zhou - One of the best experts on this subject based on the ideXlab platform.

  • phase Noise Measurement of wideband microwave sources based on a microwave photonic frequency down converter
    Optics Letters, 2015
    Co-Authors: Fangzheng Zhang, Pei Zhou
    Abstract:

    An approach for phase Noise Measurement of microwave signal sources based on a microwave photonic frequency down-converter is proposed. Using the same optical carrier, the microwave signal under test is applied to generate two +1st-order optical sidebands by two stages of electro-optical modulations. A time delay is introduced between the two sidebands through a span of fiber. By beating the two +1st-order sidebands at a photodetector, frequency down-conversion is implemented, and phase Noise of the signal under test can be calculated thereafter. The system has a very large operation bandwidth thanks to the frequency conversion in the optical domain, and good phase Noise Measurement sensitivity can be achieved since the signal degradation caused by electrical amplifiers is avoided. An experiment is carried out. The phase Noise measured by the proposed system agrees well with that measured by a commercial spectrum analyzer or provided by the datasheet. A large operation bandwidth of 5–40 GHz is demonstrated using the proposed system. Moreover, good phase Noise floor is achieved (−123  dBc/Hz at 1 kHz and −137  dBc/Hz at 10 kHz at 10 GHz), which is nearly constant over the full Measurement range.

  • Wideband Phase Noise Measurement Using a Multifunctional Microwave Photonic Processor
    IEEE Photonics Technology Letters, 2014
    Co-Authors: Fangzheng Zhang, Pei Zhou
    Abstract:

    A novel scheme for measuring the phase Noise of microwave signal sources is proposed based on the delay-line method using a multifunctional microwave photonic processor, which can simultaneously implement the electrical-to-optical conversion, provide a time delay, and control the phase of the output microwave signal. Thanks to the microwave photonic processor, the requirement for accurate phase control is relaxed and a large operation bandwidth of the phase Noise Measurement system can be achieved. An experiment is performed. The phase Noise measured by the proposed system agrees well with the result measured by a commercial spectrum analyzer, and the Noise floor of the measuring system is lower than -130 dBc/Hz at 10 kHz frequency offset. The large operation bandwidth is also verified by measuring the phase Noise of a wideband signal source in a frequency range from 5 to 40 GHz without rebuilding the system.

Takeshi Imaike - One of the best experts on this subject based on the ideXlab platform.

  • Phase Noise Measurement of RF Devices Using Full Digital Phase Noise Measurement Method
    2018 IEEE International Frequency Control Symposium (IFCS), 2018
    Co-Authors: Kazuya Kouchi, Takeshi Imaike
    Abstract:

    In this paper, we propose a new method for measuring the phase Noise of RF devices using a full digital phase Noise Measurement method. We verified that the phase Noise of an RF device could be measured by inserting a device under test (DUT) as part of the full digital phase Noise Measurement setup. A phase shifter in the 10 MHz band was used for the DUT, and its phase Noise characteristics were measured.

  • Full digital phase Noise Measurement by using two reference oscillators and multichannel ADCs
    2017 Joint Conference of the European Frequency and Time Forum and IEEE International Frequency Control Symposium (EFTF IFCS), 2017
    Co-Authors: Takeshi Imaike
    Abstract:

    It is realized that full digital phase Noise Measurement system which computes phase Noise spectrum after sampling oscillator's signal using analog to digital converter directly. However, in these reports oscillator pairs are used; i.e. DUT oscillator and reference oscillator pairs are needed. These method needs low phase Noise characteristics less than DUT oscillator for reference oscillator, or an oscillator of the same specification is required. On the other hand, in traditional (analog and digital mixed) phase Noise Measurement, it can measure the DUT's phase Noise by using two reference oscillators with calculation of cross-correlation, even if the phase Noise of the reference oscillator is greater than the DUT. However, there is no report that two reference oscillators are used in full digital phase Noise Measurement. In this paper we discuss about full digital phase Noise Measurement system using two reference oscillator. As a result, it was able to measure the DUT phase Noise using two reference oscillators which phase Noise were greater than DUT.

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

  • PM Noise Measurement at W-band
    IEEE Transactions on Ultrasonics Ferroelectrics and Frequency Control, 2014
    Co-Authors: A. Hati, Craig W. Nelson, D. A. Howe
    Abstract:

    We report a high-performance 92 to 96 GHz cross-spectrum phase modulation (PM) Noise Measurement system. Utilizing this system, we measured residual PM Noise of several amplifiers, mixers, and frequency multipliers. Data for the Measurement system Noise floor and the PM Noise of W-band components are reported. These results can serve as a temporary benchmark because little or no information is available on the PM Noise of components in this frequency range. In addition, we discuss an enhanced-performance frequency synthesizer that operates in the 92 to 96 GHz range. We achieved 5 to 10 dB improvement in the PM Noise at 96 GHz compared with our previously designed synthesizer.

  • Phase-Noise Measurement System for the Terahertz-Band
    IEEE Transactions on Terahertz Science and Technology, 2012
    Co-Authors: J. A. Desalvo, A. Hati, Caleb P. Nelson, D. A. Howe
    Abstract:

    We present phase-Noise Measurements in support of terahertz electronics. By combining even-harmonic mixers with a 2.5 GHz frequency comb, we achieve a phase-Noise Measurement system in waveguide (WR1.5) by use of cross-spectral and digital phase-Noise Measurement techniques. At 670 GHz an upper bound of this system's Noise floor is found to be -20, -40, and -60 dBc/Hz at 1, 100, and 10000 Hz offsets, respectively. In addition, a commercial, low-phase-Noise, 670 GHz source is measured at offset frequencies from 0.1 Hz to 1 MHz.

  • Phase-Noise Measurement of a 670 GHz source
    2012 IEEE International Frequency Control Symposium Proceedings, 2012
    Co-Authors: J. A. Desalvo, A. Hati, C. Nelson, D. A. Howe
    Abstract:

    We present phase-Noise Measurements in support of terahertz electronics. Using digital phase-Noise Measurement techniques and an even-harmonic mixer, we achieve a phase-Noise Measurement system in waveguide (WR1.5). At 670 GHz an upper bound of this system's Noise floor is found to be -20, -40, and -60 dBc/Hz at 1, 100, and 10000 Hz offsets, respectively. In addition, a commercial, low-phase-Noise, 670 GHz source is measured at offset frequencies from 0.1 Hz to 1 MHz.

  • A 100 GHz AM and PM Noise Measurement system: preliminary design and performance
    Proceedings of the 2002 IEEE International Frequency Control Symposium and PDA Exhibition (Cat. No.02CH37234), 2002
    Co-Authors: D. A. Howe, A. Hati, Caleb P. Nelson, F.l. Walls, J.f. Garcia Nava, A. Sen Gupta
    Abstract:

    A 100 GHz AM and PM Noise Measurement system is described. The basic approach to its construction is to apply existing state-of-the-art, cross-correlation Noise Measurement techniques to 100 GHz (W-band). The system uses two amplitude-Noise and phase-Noise detectors operating in parallel with cross-correlation spectrum analysis so that Measurement-system Noise averages down as m/sup -(1/2)/, given m available averages. The approach, widely regarded at lower frequencies as the dual-channel PM/AM Noise Measurement approach, has some new considerations in extending the frequency range to W-band. A new AM/PM modulator used to calibrate the 100 GHz Measurement system is discussed. Data are presented for the Measurement system's Noise floor. We give AM and PM Noise Measurements of an InP amplifier with a gain of 10 dB to 15 dB.

Pierre Lacroix Phase - One of the best experts on this subject based on the ideXlab platform.

  • Phase Noise Measurement of a narrow linewidth CW laser using delay line approaches
    Optics Letters, 2011
    Co-Authors: Olivier Llopis, Pierre-henri Merrer, Houda Brahimi, Khaldoun Saleh, Pierre Lacroix Phase
    Abstract:

    Two different laser phase Noise Measurement techniques are compared. One of these two techniques is based on a conventional and low-cost delay line system, which is usually set up for the linewidth Measurement of semicon-ductor lasers. The results obtained with both techniques on a high-spectral-purity laser agree well and confirm the interest of the low-cost technique. Moreover, an extraction of the laser linewidth using computer-aided design tools is performed.