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Updated: Jun 18, 2026
09:43
Transmission of Multiple Signals through an Optical Fiber Using Wavefront Shaping
Published on: March 20, 2017
Generation of optical OFDM signals using 21.4 GS/s real time digital signal processing.
Yannis Benlachtar1, Philip M Watts, Rachid Bouziane
1Optical Networks Group, Department of Electronic and Electrical Engineering, University College London, Torrington Place. London. UK. WC1E 7JE. y.benlachtar@ee.ucl.ac.uk
Optics Express
|November 13, 2009
Summary
This study presents a Field Programmable Gate Array (FPGA) based optical Orthogonal Frequency Division Multiplexing (OFDM) transmitter. The system achieves 8.36 Gb/s transmission over 200 km of fiber, limited by digital-to-analog converter resolution.
Area of Science:
- Optical communications engineering
- Digital signal processing
- Integrated circuit design
Background:
- Orthogonal Frequency Division Multiplexing (OFDM) is a spectrally efficient modulation technique.
- Field Programmable Gate Arrays (FPGAs) offer flexible hardware implementation for high-speed digital signal processing.
- Real-time digital signal processing is crucial for advanced optical communication systems.
Purpose of the Study:
- To demonstrate a real-time FPGA-based optical OFDM transmitter.
- To analyze the performance limitations of the implemented digital signal processing.
- To evaluate the system's transmission capability over optical fiber.
Main Methods:
- Implementation of a QPSK-OFDM signal generator using an 8-bit, 128-point Inverse Fast Fourier Transform (IFFT) core on an FPGA.
- Real-time digital signal processing at a sample rate of 21.4 GS/s.
- Back-to-back performance analysis and transmission over 200 km of standard single mode fiber.
Main Results:
- Successful generation of an 8.36 Gb/s optical single sideband (SSB) OFDM signal.
- Identified digital-to-analog converter (4-bit) and IFFT core (8-bit) resolution as primary performance limitations.
- Achieved a Bit Error Rate (BER) below 10(-3) over 200 km of uncompensated fiber.
Conclusions:
- The developed FPGA-based optical OFDM transmitter is suitable for high-speed optical communication.
- Hardware resolution limitations impact achievable performance.
- The system demonstrates practical feasibility for long-haul fiber transmission.
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