The performance of long-haul high speed coherent optical fiber communication systems is significantly degraded by the laser phase noise and the equalization enhanced phase noise (EEPN). In this paper, the analysis of the one-tap normalized least-mean-square (LMS) carrier phase recovery (CPR) is carried out and the close-form expression is investigated for quadrature phase shift keying (QPSK) co...

I will briefly review the field of noise-induced phase transitions, emphasizing the main differences with the phase-induced transitions and showing that they appear in different systems. I will show that a noise-induced transition can disappear after a suitable change of variables and I will also discuss the breaking of ergodicity and symmetry breaking that occur in noise-induced phase transiti...

We report a simple technique to suppress high-frequency phase noise of a Yb-based fiber optical frequency comb using an active intensity noise servo. Out-of-loop measurements of the phase noise using an optical heterodyne beat with a cw laser show suppression of phase noise by ≥7 dB out to Fourier frequencies of 100 kHz with a unity-gain crossing of ∼700 kHz. These results are enabled by the st...

Phase noise is one of the main impairments in wireless communications systems, due to its strong distortion of the transmitted signal. In this work, a discrete time phase noise model for simulation environments is proposed. This model can be used to obtain a better understanding of the effects of phase noise on the behavior of communications systems. It has already been shown that phase noise c...

The phase noise of quantum dot lasers is investigated theoretically by coupling the Langevin noise sources into the rate equations. The off-resonant populations in the excited state and in the carrier reservoir contribute to the phase noise of ground-state emission lasers through the phase-amplitude coupling effect. This effect arises from the optical-noise induced carrier fluctuations in the o...

Optoelectronic oscillators (OEOs) are hybrid RF-photonic devices that promise to be environmentally robust high-frequency RF sources with very low phase noise. Previously, we showed that Rayleigh-scattering-induced noise in optical fibers coupled with amplitude-to-phase noise conversion in photodetectors and amplifiers leads to fiber-length-dependent noise in OEOs. In this work, we report on tw...

ABSTRACT: Radar is gaining increasing credibility as a technique for rapid and accurate topographic mapping. Precision and accuracy of elevation and ground displacement assessed from Interferometry SAR (InSAR) depend essentially on phase difference or interferogram quality. The phase noise degrades the visual quality of the interferogram and increases the error in phase unwrapping results. Many...

This work describes a two-stage CMOS Voltage Ring Oscillator (VCRO) using differential delay cells are analyzed. The main aim of the paper is to increase the tuning range of the circuit and obtain a good phase noise at the cost of design complexity and power consumption. Two-stage VCRO implemented in 90 nm Technology realizes a tuning range of 53.40% and a phase noise of -156.328 dBc/Hz for a p...

This paper addresses the problem of interferometric phase noise reduction in synthetic aperture radar interferometry. A new phase noise model in the complex domain is introduced and validated by using both simulated and real interferograms. This noise model is also derived in the complex wavelet domain, where a novel noise reduction algorithm, which is not based on a windowing process and witho...

A general model is introduced which is capable of making accurate, quantitative predictions about the phase noise of different types of electrical oscillators by acknowledging the true periodically time-varying nature of all oscillators. This new approach also elucidates several previously unknown design criteria for reducing close-in phase noise by identifying the mechanisms by which intrinsic...