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Updated: Jul 1, 2025

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A Photonic System for Generating Unconditional Polarization-Entangled Photons Based on Multiple Quantum Interference
Published on: September 5, 2019
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Space-time domain equalization algorithm based on complex-valued neural network in a long-haul photonic-aided MIMO
Optics Letters
|March 1, 2024
Summary
This study introduces a novel complex-valued neural network for terahertz (THz) wireless systems, improving data transmission. The new method enhances signal accuracy and reduces complexity for future mobile broadband networks.
Area of Science:
- Optical Communications
- Wireless Communications
- Signal Processing
Background:
- The growing demand for high-bandwidth wireless services necessitates advanced mobile front-haul solutions.
- The terahertz (THz) frequency band presents a viable option for achieving ultrahigh-capacity data transmission.
Purpose of the Study:
- To investigate the integration of photonics-aided THz signal generation with multiple-input multiple-output (MIMO) and polarization-division multiplexing (PDM) technologies.
- To propose and validate a novel space-time domain equalization algorithm using MIMO-complex-valued neural networks (CVNNs).
Main Methods:
- Development of a novel space-time domain equalization algorithm based on MIMO-complex-valued neural networks (CVNNs).
- Experimental demonstration of signal transmission using photonics-aided THz generation, MIMO, and PDM.
- Transmission of 60-GBaud PDM-QPSK and 30-GBaud PDM-16QAM signals over a 100-m 2×2 wireless MIMO link at 320 GHz.
Main Results:
- Achieved bit-error rates (BER) below 3.8 × 10-3 for QPSK and 1.56 × 10-2 for 16QAM signals.
- The proposed MIMO-CVNN algorithm demonstrated superior performance compared to the MIMO-Volterra approach.
- The algorithm effectively preserves signal phase and inter-polarization relationships.
Conclusions:
- The novel MIMO-CVNN equalization algorithm offers significant advantages in calculation complexity and decision accuracy for THz wireless systems.
- This approach effectively handles phase information and inter-polarization relationships simultaneously.
- The findings support the potential of photonics-aided THz communication integrated with advanced signal processing for future high-bandwidth wireless services.
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