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09:43
Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
Bandwidth scalable, coherent transmitter based on the parallel synthesis of multiple spectral slices using optical
David J Geisler1, Nicolas K Fontaine, Ryan P Scott
1Department of Electrical and Computer Engineering, University of California, Davis, Davis, California 95616, USA.
Optics Express
|June 7, 2011
Summary
This study presents a flexible optical transmitter using dynamic optical arbitrary waveform generation. It creates high-bandwidth THz data waveforms in any modulation format, demonstrating software-defined, scalable optical transmission.
Area of Science:
- Optical communications engineering
- Signal processing
- Waveform generation
Background:
- Traditional optical transmitters have limitations in flexibility and bandwidth.
- Dynamic optical arbitrary waveform generation (OAWG) offers a potential solution for advanced optical signal synthesis.
Purpose of the Study:
- To demonstrate a novel optical transmitter capable of generating high-bandwidth THz data waveforms.
- To showcase the flexibility of the transmitter in creating various modulation formats through software control.
- To highlight the bandwidth scalability of the OAWG-based transmitter.
Main Methods:
- Utilizing parallel synthesis of multiple coherent spectral slices for OAWG.
- Employing a transmitter with 5.5 GHz electrical bandwidth and two 10-GHz spectral slices for initial demonstration.
- Generating optical waveforms in differential phase-shift keying (DPSK), quaternary phase-shift keying (QPSK), and eight phase-shift keying (8PSK) formats.
- Validating waveform quality using a real-time digital coherent receiver.
Main Results:
- Successfully generated 100-ns duration, 20-GHz optical waveforms in multiple modulation formats.
- Achieved clear eye openings and separated constellation points for the generated waveforms.
- Obtained a bit-error-rate (BER) below 9.8 × 10(-6) for DPSK and QPSK waveforms.
- Demonstrated bandwidth scalability with three-slice, 4-ns long waveform generation.
Conclusions:
- The developed optical transmitter, based on OAWG, offers a flexible and software-definable platform for high-bandwidth optical signal generation.
- The transmitter's ability to create diverse modulation formats and its scalable bandwidth make it suitable for flexible bandwidth applications.
- Experimental results validate the effectiveness and performance of the OAWG-based optical transmitter.
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