Optical phase-locked loop for coherent detection optical receiver

Abstract

A novel subcarrier-based optical phase-locked loop (SC-OPLL 1 ), with off-the-shelf optical components, is presented and demonstrated. The method, based on a continuous-wave laser and optical subcarrier modulation using a standard LiNbO 3 Mach-Zehnder modulator, allows easier practical implementation than the previously proposed OPLL circuits based on laser direct modulation.

Phase Noise Power Spectral Density Measurement of Narrow Linewidth CW Lasers Using an Optical Phase-Locked Loop

“…Declared linewidths are lower than 100 kHz for the Agilent model, and 700 kHz for the Anritsu model. The OPLL employed for phase noise measurement is an SC-OPLL [8]. The signal power at the photodiode input was set to 16 dBm, while the overall LO power was 3 dBm.…”

“…Our measurement technique is based on an optical phase-locked loop (OPLL) which can be described by a linear model. In this letter, we show experimental results obtained by using an OPLL based on sub-carrier modulation (SC-OPLL) [8]. This way, we are able to characterize CW lasers phase noise; optical oscillators with direct frequency modulation are not required.…”

Nonlinear dynamics of an optical phase locked loop in presence of additional loop time delay

“…With the advancement of optoelectronic technology, PLL systems have been designed in the optical frequency range also [7]. As such OPLLs have huge application potential and several works on OPLLs have been reported in the literature [8][9][10]. In future, OPLLs would be used in different applications, such as optical phase modulation, dispersion compensation in electrical domain, fast reconfigurable optical networks, optical sensor etc.…”

“…In future, OPLLs would be used in different applications, such as optical phase modulation, dispersion compensation in electrical domain, fast reconfigurable optical networks, optical sensor etc. [9,10]. OPLL can also be used to generate highly stable microwave carriers, which can be used in optical communication [8].…”

2.5 Gbps 2-PSK Ultra-Dense WDM Homodyne Coherent Detection Using a Sub-Carrier Based Optical Phase-Locked Loop

“…We proposed in [4][5][6] a novel and much simpler OPLL architecture based on commercial off-the-shelf optoelectronic components and without fast direct laser frequency tuning. Frequency tuning is obtained in our system through optical sub-carrier generation and tuning, and will be indicated as SC-OPLL.…”