Patryk J. Urban

OTM- and OTDR-based cost-efficient fiber fault identification and localization in Passive Optical Network

PON monitoring based on combined Optical Time Domain Reflectometry (OTDR) and Optical Transceiver Monitoring (OTM) is presented. The results on a 25-km 1∶32 PON prove the concept and show ∼0.02 dB accuracy with theoretical values.

WDM-PON Monitoring With Tunable Photon Counting OTDR

We explore the performance of a tunable optical time domain reflectometer based on single photon detection for fault location and quantification in wavelength division multiplexing (WDM)-passive optical networks based on a 32-channel cyclic arrayed waveguide grating using the S- and C-bands for upstream (156 Mb/s) and downstream (2.5 Gb/s) transmission and the L-band for monitoring. Downstream Rayleigh and Raman scattering contributions to the dark count noise were evaluated and properly filtered out with a total WDM + filter rejection ratio of 90 dB. Upstream power was found to generate the greatest contribution to the noise floor and is the limiting factor to the upstream transmission data rate. In-service monitoring experiments with full upstream and downstream power show that the proposed scheme is able to achieve dynamic range levels of up to 32 dB with 5-m spatial resolution and no measurable penalty in data transmission.

Automatic Fault Detection in WDM-PON With Tunable Photon Counting OTDR

An automatic fiber-optical fault analysis system making use of a tunable photon counting optical time-domain reflectometry (OTDR) (ν-OTDR) is proposed and demonstrated in a passive optical network testbed. The employment of the ℓ trend filter as a signal processing tool enables the minimization of the intrinsic coherent random noise impact on the acquired data and also an automatic identification of fiber faults. A feedback loop between an FPGA-based acquisition unit and the filters selections yields highly accurate automatic results and minute monitoring periods with ITU-T grid DWDM tunability, spatial resolution of 6 m and a measured 32 dB dynamic range.

Detection of fiber faults in passive optical networks

Wider deployment of fiber in the last mile is driven by increased customer needs for broadband communication services. This deployment requires solutions that reduce operational expenditures for the operator. A cost-efficient fully reliable and accurate monitoring solution supporting fault detection, identification, and localization in different fiber access architectures will be essential. In this article, we present a fast, automatic, and precise monitoring method applicable to both power-splitter- and wavelength-router-based passive optical networks through the combined techniques of optical time domain reflectometry and optical transceiver monitoring. The description of the architecture, components, and process flow is followed by tests on setups with live data transmission.

Cost-efficient remote PON monitoring based on OTDR measurement and OTM functionality

We present a method to monitor single- and cascaded-splitter TDM-PON systems based on combined techniques of Optical Time-Domain Reflectometry (OTDR) and Optical Transceiver Monitoring (OTM). The method is non-invasive to data traffic flow and requires no additional functionality (hardware or software) at the Optical Network Terminals (ONT). The description of the Fiber Plant Manager (FPM) overall architecture and components is followed by measurement results proving the concept on a 25-km 1∶32 PON testbed.

Fiber Monitoring Using a Sub-Carrier Band in a Sub-Carrier Multiplexed Radio-Over-Fiber Transmission System for Applications in Analog Mobile Fronthaul

In this paper, we describe an efficient method for monitoring fiber links utilizing sub-carrier multiplexing. By assigning a void sub-carrier frequency band for monitoring purposes, the method reuses the data transmitter without any impact on data transmission and provides capability of in-service reflectometry measurements of fiber optic lines with 10-m spatial resolution and 1.0-dB fault detection sensitivity. Its promising properties and performance enable potential application in emerging networks such as relatively short distance analogue mobile fronthaul.

Control and management requirements for a coherent ultra-dense WDM PON for lambda to the user access networks

In this paper we first highlight the arising MAC-layer requirements for a coherent ultra-dense WDM PON for full and shared lambda to the user access networks. We then report on the appropriate modifications of the XGPON standard to accommodate the MAC requirements of coherent ultra-dense WDM PONs.

Small cell strategy: meeting the indoor challenge

In this work we present an innovative solution to reach good quality of service while using mobile broadband indoors: the fiber radio-dot. This solution consists of a new architectural logical point-to-point optical link that brings the macro layer indoors. This solution provides higher bandwidth, no eavesdropping, frequency reuse, low latency, interference and network management, and cell selection. We tested the solution in the lab achieving an EVM of 0.75 %rms, SFDR of around 95 dBxHz2/3 and an LTE transmission of 75 Mbit/s.

Tuneable OTDR measurements for WDM-PON monitoring

We propose and demonstrate a tunable optical time-domain reflectometer (OTDR) for in-service monitoringof wavelength-division-multiplexed passive optical networks (WDM-PONs). The proposed method is proved for different continuous wavetuneable laser sources (CW TLS), and uses semiconductor optical amplifier (SOA) as a switch for the probe signal. We also improve the results using different methods to mitigate the interference effects.

WDM-PON fiber-fault automatic detection and Localization with 1 dB event sensitivity in drop links

Trial of live WDM-PON monitoring based on Optical Time Domain Reflectometry (OTDR) and Optical Transceiver Monitoring (OTM) is presented. The concept of cost-effective, remote and quick operation without drop-line demarcation components is demonstrated.