Single-sideband Phase Noise Research Articles

State-of-the-art RF signal generation from optical frequency division

We present the design of a novel, ultralow-phase-noise frequency synthesizer implemented with extremely-low-noise regenerative frequency dividers. This synthesizer generates eight outputs, viz. 1.6 GHz, 320 MHz, 160 MHz, 80 MHz, 40 MHz, 20 MHz, 10 MHz and 5 MHz for an 8 GHz input frequency. The residual single-sideband (SSB) phase noises of the synthesizer at 5 and 10 MHz outputs at 1 Hz offset from the carrier are -150 and -145 dBc/Hz, respectively, which are unprecedented phase noise levels. We also report the lowest values of phase noise to date for 5 and 10 MHz RF signals achieved with our synthesizer by dividing an 8 GHz signal generated from an ultra-stable optical-comb-based frequency division. The absolute SSB phase noises achieved for 5 and 10 MHz signals at 1 Hz offset are -150 and -143 dBc/Hz, respectively; at 100 kHz offset, they are -177 and -174 dBc/Hz, respectively. The phase noise of the 5 MHz signal corresponds to a frequency stability of approximately 7.6 × 10(-15) at 1 s averaging time for a measurement bandwidth (BW) of 500 Hz, and the integrated timing jitter over 100 kHz BW is 20 fs.

Fiber‐length‐dependence phase noise of injection‐locked optoelectronic oscillator

ABSTRACTA novel model of injection‐locked dual optoelectronic oscillator (ILD‐OEO) is proposed and verified by experiments in this article. We not only built an accurate model for ILD‐OEO but also analyzed the influence of fiber length on the white noise‐limited phase noise of ILD‐OEO. Results show that the single sideband (SSB) phase noise would increase when fiber delay line is long enough. © 2013 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:2568–2571, 2013

Characterization of packaged inline-type radio frequency microelectromechanical systems power sensors

This paper proposes the characterization of 8–10GHz inline-type radio frequency microelectromechanical systems (RF MEMS) power sensors on the packaging-test-fixture for power self-detection systems in RF receivers and transmitters. The sensors are used to convert a certain percentage of the RF power coupled by a MEMS membrane into thermovoltages based on Seebeck effect. Two packaging methods are studied to evaluate the RF performance by the simulation and the measurement. The effects of the temperature from 5°C to 75°C on the packaged power sensors are quantified by the measurement of the output thermovoltages, which result in the 33.2% change in sensitivity at 10GHz. After the packaging, rise and fall response times of <10ms are obtained. In addition, measured mechanical resonance frequency (f1st) of the MEMS membrane in the sensors is 78kHz. Experiments show that the single-sideband phase noise of the packaged power sensors is as low as −122dBc/Hz at the offset frequency Δf=500kHz for an input RF signal of 100mW and 9GHz, and the sensors do not generate any significant phase noise in the interested RF range.

Study on low-phase-noise optoelectronic oscillator and high-sensitivity phase noise measurement system

An analytic model for an injection-locked dual-loop optoelectronic oscillator (OEO) is proposed and verified by experiments in this paper. Based on this theoretical model, the effect of injection power on the single-sideband phase noise of the OEO is analyzed, and results suggest that moderate injection is one key factor for a balance between phase noise and spur for OEO. In order to measure superlow phase noise of OEOs, a cross-correlation measurement system based on the fiber delay line is built, in which high linear photodetector and low-phase-noise amplifier are used to improve systematic sensitivity. The cross-correlation measurement system is validated by experiments, and its noise floor for the X band is about -130 dBc/Hz at 1 kHz and -168 dBc/Hz at 10 kHz after a cross correlation of 200 times.

Intrinsic phase noise properties and frequency stability of millimetre‐wave module at 90 GHz

A report is presented on the residual intrinsic phase noise properties of a millimetre-wave module used to generate W-band signals from an X-band analogue signal generator. The 90 GHz outputs of two nominally identical millimetre-wave modules are heterodyned to measure their instantaneous frequency fluctuations and hence infer the close-to-carrier phase noise. The fractional frequency stability at 1 s integration time is 2 × 10−14, which corresponds to a total single-sideband phase noise of −50 dBc/Hz at 1 Hz Fourier frequency offset from the carrier and a residual single-sideband phase noise of −52 dBc/Hz at 1 Hz offset.

Microwave synthesis from a continuous-wave terahertz oscillator using a photocarrier terahertz frequency comb

We report low-noise microwave synthesis from radiation with a frequency of 0.3 THz using a photocarrier frequency comb in a photoconductive antenna. The synthesized microwave signal at 1 GHz is phase coherent to the 0.3 THz radiation and has a fractional instability of 1×10(-15) within 300 s averaging times and single-sideband phase noise of -105 dB/Hz at a 100 Hz offset from the carrier. This terahertz (THz)-to-microwave synthesizer is capable of being a THz frequency divider, which would be indispensable to not only THz metrology but also future high-speed wireless networks.

A tunable optoelectronic oscillator based on a tunable microwave attenuator

A novel realization of a wideband tunable optoelectronic oscillator (OEO) based on dual-port electrode Mach–Zehnder modulator (DMZM), a tunable microwave attenuator (TMA), and a chirped fiber Bragg grating (CFBG) is proposed and demonstrated. By simply adjusting the power ratio between the two arms of DMZM, the chirp of the DMZM will be tuned, and the center frequency of the microwave photonic filter will be tuned. When the OEO loop in the proposed system is closed, the output frequency of OEO is determined by the microwave photonic filter, and a high spectral purity microwave signal with a tunable frequency from 5.8 to 11GHz is generated. The single sideband (SSB) phase noise of the generated signal could reach −107.4dBc/Hz at an offset frequency of 10kHz.

Tunable optoelectronic oscillator based on a chirped Mach-Zehnder modulator

Realization of a wideband tunable optoelectronic oscillator based on a chirped Mach–Zehnder modulator (MZM) and a chirped fiber Bragg grating is proposed and demonstrated. By simply adjusting the direct-current bias of the chirped MZM, the frequency of the oscillating signal is tuned. A theoretical model is established, then verified by an experiment. A high-purity microwave signal with a tunable frequency from 5.8 to 11.8 GHz is generated. The single-sideband phase noise of the generated signal is −112.6 dBc/Hz at a frequency offset of 10 kHz.

Wavelength and Mode-Spacing Tunable Dual-Mode Distributed Bragg Reflector Laser

In this letter, we report a novel mode-beating distributed Bragg reflector (DBR) laser with dual-mode output. Both the working wavelengths and mode spacing of the dual-mode laser can be tuned when the currents injected into the DBR laser are adjusted. The tuning ranges of the laser wavelength and mode-beating frequency are [1527.20 nm, 1531.04 nm] and [91.88 GHz, 94.02 GHz] , respectively. A fourth harmonic injection locking is also demonstrated to achieve a synchronized RF output at 93.23 GHz. The phase noise of the RF output is measured by using the down-conversion method. A single sideband phase noise of 96.92 dBc/Hz with 1-MHz offset at a down-converted frequency of 13.23 GHz is achieved.

Modeling for opto-electronic oscillator considering the nonlinearity of microwave amplifier

A new model is proposed to analyze the oscillation power and phase noise characteristics of oscillation signal in the single-loop opto-electronic oscillator (OEO), and then verified by experiments. Compared with previous models, in our model, the nonlinearity of not only the E/O modulator but also the microwave amplifier is included in calculating systematic nonlinearities, so this model can describe OEO more accurately than previous models. Experiments verify the correctness of our model and results show that, compared with previous models, the oscillation power is about 10 dB lower and the minimum single-sideband phase noise after optimization is ∼3 dB higher in our experiments. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 55:715–719, 2013; View this article online at wileyonlinelibrary.com. DOI: 10.1002/mop.27428

Wideband tunable optoelectronic oscillator based on a phase modulator and a tunable optical filter

A widely tunable optoelectronic oscillator (OEO) based on a broadband phase modulator and a tunable optical bandpass filter is proposed and experimentally demonstrated. A tunable range from 4.74 to 38.38 GHz is realized by directly tuning the bandwidth of the optical bandpass filter. To the best of our knowledge, this is the widest fundamental frequency tunable range ever achieved by an OEO. The phase noise performance of the generated signal is also investigated. The single-sideband phase noise is below -120 dBc/Hz at an offset of 10 KHz within the whole tunable range.

Tunable Optoelectronic Oscillator Based on a Polarization Modulator and a Chirped FBG

A wideband-tunable optoelectronic oscillator (OEO) is proposed and experimentally demonstrated based on a tunable microwave photonic filter (MPF) consisting of a polarization modulator, a chirped fiber Bragg grating, and a polarization beam splitter (PBS). By simply adjusting the polarization state of the signal before the PBS, the center frequency of the MPF is tuned. The proposed OEO is experimentally demonstrated. A high-purity microwave signal with a tunable frequency within 5.8-11.8 GHz is generated. The single-sideband phase noise of the generated signal is -104.56 dBc/Hz at 10-kHz offset.

A low phase noise microwave source for atomic spin squeezing experiments in 87Rb

We describe and characterize a simple, low cost, low phase noise microwave source that operates near 6.800 GHz for agile, coherent manipulation of ensembles of (87)Rb. Low phase noise is achieved by directly multiplying a low phase noise 100 MHz crystal to 6.8 GHz using a nonlinear transmission line and filtering the output with custom band-pass filters. The fixed frequency signal is single sideband modulated with a direct digital synthesis frequency source to provide the desired phase, amplitude, and frequency control. Before modulation, the source has a single sideband phase noise near -140 dBc/Hz in the range of 10 kHz-1 MHz offset from the carrier frequency and -130 dBc/Hz after modulation. The resulting source is estimated to contribute added spin-noise variance 16 dB below the quantum projection noise level during quantum nondemolition measurements of the clock transition in an ensemble 7 × 10(5) (87)Rb atoms.

A Four-Channel 94-GHz SiGe-Based Digital Beamforming FMCW Radar

This paper presents a multi-channel frequency-modulated continuous-wave (FMCW) radar sensor operating in the frequency range from 91 to 97 GHz. The millimeter-wave radar sensor utilizes an SiGe chipset comprising a single signal-generation chip and multiple monostatic transceiver (TRX) chips, which are based on a 200-GHz fT HBT technology. The front end is built on an RF soft substrate in chip-on-board technology and employs a nonuniformly distributed antenna array to improve the angular resolution. The synthesis of ten virtual antennas achieved by a multiple-input multiple-output technique allows the virtual array aperture to be maximized. The fundamental-wave voltage-controlled oscillator achieves a single-sideband phase noise of -88 dBc/Hz at 1-MHz offset frequency. The TX provides a saturated output power of 6.5 dBm, and the mixer within the TRX achieves a gain and a double sideband noise figure of 11.5 and 12 dB, respectively. Possible applications include radar sensing for range and angle detection, material characterization, and imaging.

Effects of the biasing voltage of modulator on the phase noise of opto‐electronic oscillator

AbstractLow biasing technique has been used recently to reduce the relative intensity noise of the microwave optical fiber links.In this article, the possibility of reducing the phase noise of opto‐electronic oscillator (OEO) by using low‐biased optical fiber link is verified. Theoretical and experimental results show that the single sideband (SSB) phase noise of OEO can be reduced at the maximum by 2.8 dB in low‐biased microwave optical fiber links when compared with conventional quadrature‐biased links. The optimal biasing angle corresponding to the minimum SSB phase noise increases with the intensity of the optical power into modulator. © 2012 Wiley Periodicals, Inc. Microwave Opt Technol Lett 54:689–692, 2012; View this article online at wileyonlinelibrary.com. DOI 10.1002/mop.26642

41 GHz and 10.6 GHz low threshold and low noise InAs/InP quantum dash two-section mode-locked lasers in L band

This paper reports recent results on InAs/InP quantum dash–based, two-section, passively mode-locked lasers pulsing at 41 GHz and 10.6 GHz and emitting at 1.59 μm at 20 °C. The 41-GHz device (1 mm long) starts lasing at 25 mA under uniform injection and the 10.6 GHz (4 mm long) at 71 mA. Their output pulses are significantly chirped. The 41-GHz laser exhibits 7 ps pulses after propagation in 60 m of a single-mode fiber. The 10.6-GHz laser generates one picosecond pulses with 545 m of a single-mode fiber. Its single side-band phase noise does not exceed –80 dBc/Hz at 100 kHz offset, leading to an average timing jitter of 800 fs.

Generation of microwave subcarrier phase modulation signal based on optical injection into a semiconductor laser

Radio-over-fiber technology has become an important solution for ultra wide band wireless communication, and the convergence of signal processing between optics and microwave/millimeter wave is more crucial. In this paper, microwave subcarrier phase modulation signal generation based on optical injection into a semiconductor Fabry-Perot laser is proposed. According to the period-one(P1) oscillation effect of laser output optical field, one modulation component of the optical phase modulation signal is amplified by sideband of P1 oscillation. The amplified component beats with injection optical carrier to generate microwave subcarrier. The phase shifts lead to the phase shift of subcarrier, thus the phase information is converted into phase information about microwave subcarrier. The optical phase-shift-keying signals at 1.3 Gb/s, 2.7 Gb/s, 2 Gb/s are converted into microwave subcarrier phase modulation signal, and the single sideband phase noise is measured. By logically comparing the demodulated signal with original signal, the feasibility of data information conversion is proved experimentally.

Ultra-Stable Very-Low Phase-Noise Signal Source for Very Long Baseline Interferometry Using a Cryocooled Sapphire Oscillator

The design and implementation of a novel frequency synthesizer based on low phase-noise digital dividers and a direct digital synthesizer is presented. The synthesis produces two low noise accurate tunable signals at 10 and 100 MHz. We report the measured residual phase noise and frequency stability of the syn thesizer and estimate the total frequency stability, which can be expected from the synthesizer seeded with a signal near 11.2 GHz from an ultra-stable cryocooled sapphire oscillator (cryoCSO). The synthesizer residual single-sideband phase noise, at 1-Hz offset, on 10and 100-MHz signals was -135 and -130 dBc/Hz, respectively. The frequency stability contributions of these two sig nals was σy = 9 × 10-15 and σy = 2.2 × 10-15, respectively, at 1-s integration time. The Allan deviation of the total fractional frequency noise on the 10- and 100-MHz signals derived from the synthesizer with the cry oCSO may be estimated, respectively, as σy ≈ 3.6 × 10-15 τ-1/2 + 4 × 10-16 and σy ≈ s 5.2 × 10-2 × 10-16 τ-1/2 + 3 × 10-16, respectively, for 1 ≤ τ <; 104s. We also calculate the coherence function (a figure of merit for very long baseline interferometry in radio astronomy) for observation frequencies of 100, 230, and 345 GHz, when using the cry oCSO and a hydrogen maser. The results show that the cryoCSO offers a significant advantage at frequencies above 100 GHz.

A 122-GHz SiGe-Based Signal-Generation Chip Employing a Fundamental-Wave Oscillator With Capacitive Feedback Frequency-Enhancement

This paper presents a highly integrated and fully balanced signal generation block comprising a fundamental-wave voltage-controlled oscillator (VCO), an output buffer, and a configurable frequency divider stage (prescaler). The VCO introduces a negative resistance structure in conjunction with capacitive cross-coupling. This compound structure allows fundamental oscillation to be sustained at high frequencies while providing wide tuning ranges. The capabilities of the capacitive feedback were analyzed using a linear transistor model, and boundary conditions, which support the early design phase, were derived. The chip was fabricated in a SiGe technology with 300-GHz <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</i> <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">max</sub> HBTs. The output frequency of the monolithic microwave integrated circuit is centered at 122 GHz and provides a tuning range of 16 GHz at an average single-sideband phase noise of -95 dBc/Hz at 1 MHz offset frequency. Possible applications include ISM applications at 122 GHz and short-range radar systems with wide tuning ranges.

Robust photonic radio frequency multiplication technique by utilizing Fabry–Pérot laser diode injection locking

A simple and robust photonic radio frequency multiplication with continuously tunable multiplication factor by using a Fabry-Pérot laser diode (FP-LD) is proposed and demonstrated. In a FP-LD, the four-wave mixing effect can create new harmonic components, and the injection-locking behavior is able to lock and amplify one of the sidebands. When the output signal beats on a high speed photodetctor, the multiplication frequencies with a factor more than 41 can be obtained. The tunability is implemented by detuning the injection wavelength. In the experimental demonstration, the frequency components around 20 GHz are generated from a 500 MHz (or 1 GHz) sinusoidal signal. The measured single sideband phase noise is −95 dBc/Hz at a 10 kHz frequency offset.