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300-GHz Photonics-Aided Wireless 2 × 2 MIMO Transmission over 200 m Using GMM-Enhanced Duobinary Unsupervised
Luhan Jiang1, Jianjun Yu1, Qiutong Zhang1
1The State Key Laboratory of ASIC and System, Key Laboratory for Information Science of Electromagnetic Waves (MoE), School of Information Science and Technology, Fudan University, Shanghai 200433, China.
Sensors (Basel, Switzerland)
|February 13, 2026
Summary
This study demonstrates a 100 Gbit/s terahertz wireless communication system using polarization division multiplexing and advanced signal processing. Techniques like duobinary shaping and a novel neural network overcome transmission challenges, achieving high data rates over 200 meters.
Area of Science:
- Wireless Communication
- Terahertz Technology
- Signal Processing
Background:
- Terahertz (THz) wireless communication promises ultra-high bandwidth for next-generation networks.
- Challenges include severe propagation loss and atmospheric absorption, limiting data rates and transmission distances.
- Existing systems require solutions to enhance capacity and overcome component bandwidth limitations.
Purpose of the Study:
- To enhance system capacity and overcome bandwidth limitations in THz communication.
- To address channel noise and improve signal-to-noise ratio (SNR) for reliable data transmission.
- To demonstrate a high-capacity, long-distance THz wireless transmission system.
Main Methods:
- Utilized polarization division multiplexing (PDM) and antenna diversity techniques to increase system capacity.
- Employed duobinary shaping and maximum likelihood sequence detection (MLSD) to address component bandwidth limitations.
- Proposed a Gaussian mixture model (GMM)-enhanced duobinary unsupervised adaptive convolutional neural network (DB-UACNN) for channel noise mitigation.
- Demonstrated a 2x2 multiple-input multiple-output (MIMO) photonic-aided THz wireless transmission system at 300 GHz.
Main Results:
- Duobinary shaping achieved an SNR gain of up to 1.87 dB (X-polarization) and 1.70 dB (Y-polarization).
- The GMM-enhanced DB-UACNN provided additional SNR gains of up to 2.59 dB (X-polarization) and 2.63 dB (Y-polarization).
- A 100 Gbit/s data rate was successfully transmitted over 200 meters, meeting the 7% hard-decision forward error correction (HD-FEC) threshold.
Conclusions:
- The integrated system effectively overcomes THz communication challenges, enhancing both capacity and transmission distance.
- The proposed GMM-enhanced DB-UACNN significantly improves SNR and noise resilience in duobinary systems.
- Achieved a record 100 Gbit/s transmission rate over 200 m, paving the way for practical THz wireless networks.
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