Noise Floor Reduction of an Er:Fiber Laser-Based Photonic Microwave Generator

Author

Jiang, Haifeng ; Taylor, Jennifer ; Quinlan, Franklyn ; Fortier, Tara ; Diddams, Scott A.

Author_Institution

Nat. Inst. of Stand. & Technol., Boulder, CO, USA

Volume

3

Issue

6

fYear

2011

Firstpage

1004

Lastpage

1012

Abstract

The generation of microwaves from optical signals suffers from thermal and shot noise inherent in the photodetection process. This problem is more acute at lower pulse repetition rates where photodiode saturation limits the achievable signal-to-noise ratio. In this paper, we demonstrate a 10-15-dB reduction in the 10-GHz phase noise floor by multiplication of the pulse repetition rate. Starting with a 250-MHz fundamentally mode-locked erbium (Er):fiber laser, we compare the following two different approaches to repetition rate multiplication: 1) Fabry-Perot cavity filtering and 2) a cascaded, unbalanced Mach-Zehnder (MZ) fiber-based interferometer. These techniques reduce the phase noise floor on the 10-GHz photodetected harmonic to -158 and -162 dBc/Hz, respectively, for Fourier frequencies higher than 100 kHz.

Keywords

Fabry-Perot interferometers; Mach-Zehnder interferometers; erbium; laser mode locking; microwave generation; optical fibre amplifiers; Fabry-Perot cavity filtering; Mach-Zehnder fiber-based interferometer; fiber laser-based photonic microwave generator; frequency 10 GHz; frequency 250 MHz; mode-locked laser; noise floor reduction; optical signals; Cavity resonators; Laser mode locking; Laser noise; Masers; Phase noise; Photodiodes; Erbium lasers; fiber lasers; fiber optical systems; mode-locked lasers; photodetectors and microwave photonics signal;

fLanguage

English

Journal_Title

Photonics Journal, IEEE

Publisher

ieee

ISSN

1943-0655

Type

jour

DOI

10.1109/JPHOT.2011.2171480

Filename

6043781