Overview
IEC 61290-11-1:2008 is an international standard developed by the International Electrotechnical Commission (IEC) focusing on test methods for polarization mode dispersion (PMD) in optical amplifiers (OAs). The standard applies to all commercially available optical amplifiers, including optical fibre amplifiers (OFAs) using active fibres, semiconductor optical amplifiers (SOAs), and planar waveguide optical amplifiers (PWOAs). It specifically addresses the measurement of the polarization mode dispersion parameter using the Jones matrix eigenanalysis (JME) technique.
This second edition (2008) is a technical revision that expands coverage to additional types of OAs and updates references, maintaining a reference framework for the telecommunications industry to assess the impact of PMD on optical signals amplified by OAs.
Key Topics
Polarization Mode Dispersion (PMD)
- PMD causes pulse broadening due to differential group delay (DGD) between orthogonally polarized components.
- PMD effects degrade the performance of high-speed optical communication systems.
- Measuring PMD is crucial for quantifying signal distortion in optical amplifiers.
Jones Matrix Eigenanalysis (JME) Method
- JME is a test method that uses the Jones matrix representation of an OA’s transmission properties to compute PMD.
- The method requires measuring the normalized Stokes parameters at two closely spaced wavelengths.
- Primarily applicable to pumped (powered) optical amplifiers.
- Immune to polarization-dependent gain (PDG) and loss (PDL) effects up to approximately 1 dB.
Test Apparatus Components
- Tuneable Laser Source: Provides narrow-linewidth, tunable light over a wavelength range to excite the OA.
- Polarization Adjuster: Sets the input polarization state to roughly circular polarization for consistent measurements.
- Linear Polarizers: Three polarizers arranged at approximately 45° relative angles to analyze polarization states.
- Optical Input/Output Optics: Include single-mode fibre pigtails or lens systems to couple light to and from the OA under test.
- Polarimeter: Measures output polarization states; wavelength sensitivity must cover the test source spectrum.
Measurement Procedure and Calculations
- Coupling the laser output through the polarization adjuster and polarizers into the OA.
- Measuring the output polarization states via the polarimeter across a wavelength interval.
- Calculating DGD, average DGD, and maximum DGD using Jones matrix eigenanalysis techniques.
- Accounting for amplified spontaneous emission (ASE) which reduces the degree of polarization (DOP) at the output.
Applications
IEC 61290-11-1:2008 is essential for manufacturers, testers, and system designers working with:
- Optical fibre amplifiers (OFAs) in long-haul and metro telecommunications networks.
- Semiconductor optical amplifiers (SOAs) used for signal boosting in fiber optic links.
- Planar waveguide optical amplifiers (PWOAs) integrated into photonic circuits.
- Assessment of PMD impact on system performance and verification of optical amplifier compliance to quality standards.
- Enhancing reliability and optimizing design parameters for high-speed optical communication systems sensitive to polarization effects.
- Supporting research and development in fiber optic component characterization and measurement consistency.
Related Standards
- IEC 61282-9: Fibre optic communication system design guides - Guidance on Polarization Mode Dispersion measurements and theory.
- IEC 61292-5: Optical amplifiers - Part 5: Polarization mode dispersion parameter - General information.
- The broader IEC 61290 series on optical amplifier test methods.
Practical Value
Adhering to IEC 61290-11-1:2008 ensures:
- Standardized measurement of PMD enabling consistent evaluation across devices and vendors.
- Accurate determination of differential group delay mitigating risks of signal degradation.
- Insight into the interaction of amplified spontaneous emission and polarization properties.
- Enhanced quality control in manufacturing optical amplifiers to meet strict telecom industry requirements.
- Facilitated maintenance and performance optimization of optical networks by understanding polarization effects in amplification.
Use this standard to implement robust PMD testing protocols, improving the performance and reliability of optical amplifiers in modern fibre optic networks.