Novel OBI noise reduction technique by using similar-OBI estimation in optical multiple access uplink

Area of Science:

• Optical communications
• Signal processing

Background:

• Optical beat interference (OBI) noise is a significant challenge in optical multiple access systems, particularly in passive optical networks (PONs).
• Existing methods for OBI noise reduction may not be sufficient for high-performance uplinks operating on the same wavelength.

Purpose of the Study:

• To present a novel optical beat interference (OBI) noise reduction technique for optical multiple access uplinks.
• To enhance signal quality and improve the signal-to-noise ratio (SNR) in orthogonal frequency division multiplexing access (OFDMA) PON systems.

Main Methods:

• A digital signal processing technique is employed to estimate and subtract OBI noise.
• A similar-OBI is derived by transmitting a radio frequency (RF) clipping tone outside the signal band.
• The method was validated through both numerical simulations and experimental testing.

Main Results:

• The proposed OBI noise reduction method effectively mitigated noise in an OFDMA-PON uplink.
• Signal-to-noise ratio (SNR) improved significantly, increasing from 4.4 dB to 10.6 dB.
• The technique demonstrated successful OBI noise reduction and signal enhancement.

Conclusions:

• The novel OBI noise reduction technique is effective for optical multiple access uplinks.
• The digital signal processing approach offers a viable solution for improving SNR in OFDMA-PON systems.
• This method contributes to enhanced performance in wavelength-shared optical networks.