Reconfigurable Fiber Dispersion Reference Module

Resolve Bottlenecks,
Find Innovative Solutions
Generate Solutions

Solution Overview

Problem

Current link models in industry standards for optical channels, particularly multimode fibers, inadequately describe fiber dispersion phenomena, leading to inconsistent performance evaluation of transceivers due to unaccounted modal and chromatic dispersion interactions, and fail to effectively test worst-case conditions, especially at higher baud rates and in single mode fiber channels.

Innovation Solution

A Multi-Port/Multi-Channel Reconfigurable Fiber Dispersion Reference Module (MM-FDRM) is designed to provide a controlled environment for testing VCSEL-based transceivers by incorporating fibers of varying characteristics and lengths, with a refractive index profile optimized for worst-case modal bandwidth and chromatic dispersion, allowing for efficient and repeatable multichannel testing.

Engineering Contradictions & Design Principles

VSEngineering Contradiction Analysis

1Device complexity

If link models assume modal and chromatic dispersions do not interact, then estimation of worst-case channels is simplified, but performance evaluation of transceivers becomes inconsistent with experimental results

Engineering Contradiction:
Improvelink model complexityVSAvoidtransceiver performance evaluation accuracy
Core Design Contradiction:
Device complexityVSMeasurement precision

Solution Approach 1:

The patent introduces a new parameter α (alpha) that defines the refractive index profile shape to control the interaction between modal and chromatic dispersions. By adjusting this parameter, the system can create fiber channels with different dispersion characteristics, enabling accurate worst-case scenario testing while maintaining manageable model complexity through a single controlling parameter.

Inventive Principle:
Principle #35Parameter changes

Solution Approach 2:

The patent creates dynamically configurable fiber channels that can switch between different dispersion interaction scenarios. The reconfigurable module allows testing under varying modal bandwidth and chromatic dispersion conditions, enabling the system to adapt to different worst-case scenarios rather than relying on static assumptions.

Inventive Principle:
Principle #15Dynamics

2Adaptability or versatility

If fibers with bandwidth within the critical region are manufactured, then worst-case channel testing is enabled, but manufacturing yield decreases due to variability

Engineering Contradiction:
Improveworst-case channel testing capabilityVSAvoidfiber manufacturing yield
Core Design Contradiction:
Adaptability or versatilityVSEase of manufacture

Solution Approach 1:

Instead of manufacturing multiple fiber types with different characteristics, the patent creates a reference module that copies or simulates various fiber channel conditions using a single standardized fiber. The reconfigurable module replicates different modal bandwidth and chromatic dispersion scenarios, eliminating the need to manufacture low-yield critical-region fibers while maintaining testing capability.

Inventive Principle:
Principle #26Copying

Solution Approach 2:

The patent introduces a reconfigurable reference module as an intermediary between the transceiver under test and the actual fiber channel. This intermediary can simulate different fiber characteristics (OM3, OM4, etc.) and dispersion conditions, allowing worst-case testing without requiring physical fibers manufactured to precise critical specifications.

Inventive Principle:
Principle #24Intermediary (Mediator)

3Length of stationary object

If single mode fiber is used for longer reaches, then transmission distance is improved, but performance degrades at higher baud rates due to multipath interference and chromatic dispersion

Engineering Contradiction:
Improvetransmission reachVSAvoidhigh baud rate transmission reliability
Core Design Contradiction:
Length of stationary objectVSReliability

Solution Approach 1:

The patent applies different quality characteristics to different segments or configurations of the transmission channel. The reconfigurable module can locally adjust chromatic dispersion and modal bandwidth parameters to create optimal channel conditions for specific baud rates and reach requirements, rather than using a uniform fiber type throughout.

Inventive Principle:
Principle #3Local quality

4Adaptability or versatility

If multiple fiber organizers with different characteristics are integrated into a single module, then multichannel testing capability is improved, but device complexity increases

Engineering Contradiction:
Improvemultichannel testing capabilityVSAvoidfiber drum structure complexity
Core Design Contradiction:
Adaptability or versatilityVSDevice complexity

Solution Approach 1:

The patent designs a universal reconfigurable reference module that can perform multiple testing functions through a single standardized interface. The fiber drum structure with rotatable organizers allows one module to test multiple transceiver types and multiple channel conditions, achieving multi-functionality without proportionally increasing operational complexity.

Inventive Principle:
Principle #6Universality (Multi-functionality)

Applied Scientific Principles

This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.

Function Achieved in This Case

The MM-FDRM enables precise evaluation and selection of transceivers across different design and production stages, effectively simulating worst-case conditions to ensure reliable high-speed data transmission by accounting for modal and chromatic dispersions, thereby improving the accuracy of performance testing.

Implementation Method 1

The new shape of the refractive index profile is designed to provide worst-case EMB, while consistently exacerbating chromatic dispersion and mode partition noise

Methodology Applied
Scientific EffectModal dispersion: Dispersion (of waves)

Implementation Method 2

The new shape of the refractive index profile is designed to provide worst-case EMB, while consistently exacerbating chromatic dispersion and mode partition noise

Methodology Applied
Scientific EffectChromatic dispersion: Dispersion (of waves)

Implementation Method 3

A fiber organizer containing fibers of different characteristics or different lengths. Multiple organizers can be placed on a single rotational axis to form what is referred to herein as a fiber drum

Methodology Applied
Scientific EffectRefraction: Refraction

Data Source

PatentEP3578947B1Multi-port multi-channel reconfigurable fiber dispersion reference module
Publication Date: 2021.05.05 PANDUIT CORP
  • EP3578947B1 patent drawingFigure 1~3
  • EP3578947B1 patent drawingFigure 4~5
  • EP3578947B1 patent drawingFigure 6~7

AI summary

A fiber dispersion reference module has an enclosure with at least one fiber optic port and at least one inner rotating element. Each element having a plurality of optical channels, the enclosure and inner rotating element configured such that the rotation of the inner rotating element relative to the enclosure allows the fiber optic port of the enclosure to change its coupling between the plurality of optical channels in the inner rotating element.