Research Of Optical Performance Monitoring Techniques

As the future all-optical networks tend capacity, dynamic, reconfigurable and transparent, in order to manage this complex optical networks, the need for performance monitoring system to help confirm the link and to take measures to prevent the deterioration degree of the network system failure, avoid ISP and a huge loss of users. Performance monitoring technology compared to electric fields, optical network performance monitoring technology has many obvious advantages, such as wavelength and velocity transparent and can be applied to different optical domain modulation formats. To provide accurate, repeatable light will be the cornerstone of future performance monitoring optical intelligent network. This article dedicated to the research of new optical performance monitoring technology, the main work is as follows:First of all, this paper starts from the current development needs of optical networks and describes the performance of the optical performance monitoring technology. Then this paper focuses on the main content of the current OPM technology research, reviewed the three main technology that is now widely adopted and proposed monitoring technologies.Second, analysis techniques to study the RF, which is extracted by the spectrum presented in damage to the characteristic monitor transmitter without modification, stability, facilitate monitoring phase modulation signal.Third, we propose using RF spectrum analyzing techniques for investigating the performances of monitoring CD and PMD independently and simultaneously:First, we propose a new PMD-insensitive CD monitoring technique using offset band-stop filtering (BSF). The theoretical analysis is presented and the performance for80Gb/s NRZ-DQPSK signal is demonstrated. The offset frequency, bandwidth and DGD impacts are investigated.310ps/nm CD monitoring range with32.5dB CR can be achieved. The DGD tolerance is15ps.Second, we investigate the technique of CD-insensitive PMD monitoring technique using band-stop filtering. A BSF at10GHz away from the carrier center is used to filter the signal and then the RF tone at10GHz is detected. The performance for80Gb/s NRZ-DQPSK signal is demonstrated.50ps DGD monitor range with CR51.1dB can be achieved. The CD tolerance is50ps/nm. The impacts of RF frequency, the bandwidth and the shape of the BSF, and CD to the performances are considered.Finally, we propose a technique which can simultaneously monitor the CD and PMD using two BSF with different central frequencies. The performance for80Gb/s NRZ-DQPSK signal is demonstrated. It can monitor the CD of0-318ps/nm and DGD of0-50ps. The DGD tolerance for CD monitoring port is15ps and the CD tolerance for DGD port is175ps/nm.