Modulating signal with polarization modulator (PolM) is the simplest method for polarization shift keying (PolSK) in free space optical communication. However, this method has an intrinsic drawback on degree of polarization (DOP) reduction for the existence of polarization mode dispersion (PMD) in PolM. In this work, we analyze this change of DOP and its influence on PolSK using coherency matrix. We demonstrate that the decrease of DOP after PolM will generate extra loss and bit error ratio (BER) for PolSK communication, while this loss and BER will aggravate with the increase of laser linewidth and PolM length. For a practical PolSK system, laser linewidth should be less than 0.008nm.

Download full-text PDF

Source
http://dx.doi.org/10.1364/OE.23.008639DOI Listing

Publication Analysis

Top Keywords

laser linewidth
12
polarization modulator
8
polarization shift
8
shift keying
8
free space
8
space optical
8
optical communication
8
polarization
6
influence laser
4
linewidth polarization
4

Similar Publications

As a low-energy method to increase the data rate of optical links in data centers, we propose self-homodyne Nyquist optical time division multiplexing (OTDM). In Nyquist OTDM, spectrally efficient high-baud rate signals can be generated exceeding the limit of electronic signal processing. However, full integration of OTDM systems has not been reported, mainly because of the complicated signal detection scheme, which involves demultiplexing and clock recovery.

View Article and Find Full Text PDF

State-of-the-art laser frequency stabilization is limited by miniscule length changes caused by thermal noise. In this work, a cavity-length-insensitive frequency stabilization scheme is implemented using strong dispersion in a 21 mm long cavity with a europium-ion-doped spacer of yttrium orthosilicate. A number of limiting factors for slow light laser stabilization are evaluated, including the inhomogeneous and homogeneous linewidth of the ions, the deterioration of spectral windows, and the linewidth of the cavity modes.

View Article and Find Full Text PDF

Presented is an O-band silicon photonics dual-polarization coherent/IMDD modulator integrated with semiconductor optical amplifiers and tunable laser to enhance the short-reach link budget. The laser demonstrated output power >6 dBm and a <250 kHz linewidth over a 14 nm tuning range. Modulators paired with custom 64 Gbaud QPSK drivers exhibited improved analog link sensitivity compared to similar devices without integrated gain sections.

View Article and Find Full Text PDF

The rigid Fabry-Pérot (F-P) cavity has emerged as the preferred core sensing component for optical pressure, vibration, and acoustic sensing in harsh environments, owing to its high reliability and structural stability. However, due to the inadequate temperature resistance of the optical dielectric film, maintaining a high level of precision in the rigid F-P cavity at elevated temperatures proves to be challenging. Volume Bragg grating (VBG) is a three-dimensional optical element modified by a femtosecond laser within a transparent glass medium to create a periodic refractive index distribution.

View Article and Find Full Text PDF

We detail here the general principle of a self-adaptive oscillator in which the intertwined operation of a 100-m-long active optical resonator and a standard semiconductor laser mutually coupled by stimulated Brillouin scattering offers an ultimate high spectral purity. Single frequency operation of this self-adaptive photonic oscillator is achieved without any servo locking or stabilization electronics. In free running operation, this principle leads to a Lorentzian linewidth of 40 mHz and a Flicker noise linewidth of 200 Hz for 0.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!