Phase Noise refers to the random fluctuations or variations in the phase of a periodic signal, typically a sinusoidal waveform. These variations introduce uncertainty and instability in the timing of the signal, affecting its coherence and precision. Phase noise is a crucial consideration in various electronic systems, particularly in communication systems and oscillators, where maintaining accurate and stable phase relationships is essential for reliable performance.


Vibration Detection and Localization using Modified Digital Coherent Telecom Transponders

We demonstrate a vibration detection and localization scheme based on bidirectional transmission of telecom signals with digital coherent detection at the receivers. Optical phase is extracted from the digital signal processing blocks of the coherent receiver, from which the vibration component is extracted by bandpass filtering, and the position along the cable closest to the vibration’s epicenter is recovered by correlation. We demonstrate our scheme first using offline experiment with 200-Gb/s DP-16QAM, and we report field trial results over installed fiber to detect real-world vibration events.

A Dispersion Managed Phase Only Modulation 18 GHz Optoelectronic Oscillator

In this manuscript, we propose and experimentally demonstrate a dispersion-controlled optoelectronic oscillator with phase only modulator at 18 GHz. The generated microwave signal has a phase noise of −108 dBc/Hz at 10 kHz offset frequency and the integrated timing jitter is calculated to be 16.2 fs (1 kHz to 100 MHz) and 20 fs (1kHz to Nyquist).