Real-time OFDM transmitter beyond 100 Gbit/s

Area of Science:

• Digital Signal Processing
• Telecommunications Engineering
• Field-Programmable Gate Arrays (FPGAs)

Background:

• High-speed Orthogonal Frequency Division Multiplexing (OFDM) transmitters necessitate efficient digital signal processing, particularly for the Fourier Transform.
• Current Fast Fourier Transform (FFT) algorithms face challenges in optimizing performance and chip area utilization for real-time applications exceeding 100 Gbit/s.

Purpose of the Study:

• To present an alternative to the conventional FFT algorithm for high-performance OFDM transmitters.
• To demonstrate a novel FPGA implementation utilizing look-up tables for enhanced processing speed and reconfigurability.

Main Methods:

• Development of an FPGA-based digital signal processing architecture.
• Implementation of an optimized look-up table strategy to replace traditional FFT algorithms.
• Design of a real-time single polarization OFDM transmitter architecture.

Main Results:

• Achieved a data stream rate exceeding 100 Gbit/s, specifically 101.5 Gbit/s.
• Demonstrated nanosecond-range channel equalization and switching times without code re-loading.
• Successfully modulated 58 subcarriers using 16 Quadrature Amplitude Modulation (16QAM).

Conclusions:

• The proposed look-up table-based approach offers a viable and efficient alternative to FFT for high-speed OFDM systems.
• This method enables unprecedented real-time data rates and rapid reconfiguration capabilities in FPGA-based transmitters.
• The successful demonstration paves the way for next-generation high-capacity wireless communication systems.