Switched Optical Receiver for High-Bandwidth Signal Testing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Current high-speed optical signal test and measurement systems require numerous expensive electronic components, such as multiple analog-to-digital converters and optical-to-electrical detectors, making it costly and difficult to upgrade them for higher bandwidths.
Innovation Solution
The implementation of an optical oscilloscope with an optical receiver front end that uses optical switching and digital signal processing to combine and delay in-phase and quadrature information, reducing the need for multiple converters by serially capturing and reconstructing optical field information on a single detector and A/D converter.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If multiple analog-to-digital converters and optical-to-electrical detectors are used to achieve high-speed optical signal measurement, then measurement precision and bandwidth are improved, but device complexity and cost increase dramatically
Solution Approach 1:
The patent combines multiple detection functions into a single optical detector by using optical switching to sequentially route different signal components (in-phase and quadrature information) to the same detector. This merging approach maintains measurement precision while dramatically reducing the number of required electronic components, directly resolving the contradiction between measurement capability and device complexity
Solution Approach 2:
The patent employs periodic optical switching to sequentially capture in-phase and quadrature signal components at different time instances. The optical switch periodically routes different signal portions to the single detector in a time-division multiplexed manner, enabling complete signal reconstruction with one detector instead of multiple simultaneous detectors, thus reducing complexity while preserving measurement precision
2Device complexity
If the number of analog-to-digital converters is reduced to lower cost, then device cost and complexity are reduced, but the ability to capture and process optical field information is compromised
Solution Approach 1:
The patent performs preliminary optical processing of the signal by using optical switching to pre-separate and route in-phase and quadrature components to the single detector in sequence. This preliminary optical action ensures that all necessary field information is captured before detection, preventing information loss even though only one converter is used
Solution Approach 2:
The patent introduces an optical switch as an intermediary device between the optical signal source and the single detector. This intermediary performs time-division multiplexing of the signal components in the optical domain, ensuring that complete optical field information is delivered to the detector sequentially, thereby preventing information loss while enabling the use of a single converter
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
This approach significantly reduces the number of required electronic components, lowering costs and enabling more efficient high-speed optical signal testing and measurement by using optical techniques in combination with digital signal processing.
Implementation Method 1
an optical hybrid configured to receive the at least one input optical signal and at least a second optical signal. The optical hybrid is configured to provide, by the first output optical signal, in-phase information of the at least one input optical signal, and to provide, by the second output optical signal, quadrature information of the at least one input optical signal
Implementation Method 2
An optical detector configured to receive a combined optical signal from the optical combiner and to produce therefrom an analog-electrical signal representative of the combined optical signal
Data Source
AI summary
An apparatus, e.g. an optical oscilloscope, includes an optical receiver front end, including an optical device, and an optical delay. The receiver front end is configured to receive at least one input optical signal and produce by the optical device at least first and second output optical signals. The receiver front end is further configured to gate said at least one input optical signal or said at least first and second output optical signals. An optical combiner is configured to combine said at least first and second output optical signals, and the optical delay is located in an optical path of said first optical output signal between said optical receiver front end and the optical combiner. An optical detector is configured to receive a combined optical signal from said optical combiner and to produce therefrom an analog-electrical signal representative of the combined optical signal.