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Fotónica de 300 GHz asistida por transmisión inalámbrica MIMO 2 × 2 sobre 200 m mediante CNN adaptativa no
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
Resumen
Este estudio demuestra un sistema de comunicación inalámbrica de terahertzios de 100 Gbit/s que utiliza multiplexación por división de polarización y procesamiento avanzado de señales. Técnicas como la conformación duobinaria y una novedosa red neuronal superan los desafíos de transmisión, logrando altas tasas de datos a lo largo de 200 metros.
Área de la Ciencia:
- Comunicaciones inalámbricas
- Tecnología de terahertzios
- Procesamiento de señales
Sus antecedentes:
- La comunicación inalámbrica de terahertzios promete un ancho de banda ultra alto para las redes de próxima generación.
- Los desafíos incluyen una severa pérdida de propagación y absorción atmosférica, lo que limita las tasas de datos y las distancias de transmisión.
- Los sistemas existentes requieren soluciones para mejorar la capacidad y superar las limitaciones de ancho de banda de los componentes.
Objetivo del estudio:
- Mejorar la capacidad del sistema y superar las limitaciones de ancho de banda en la comunicación THz.
- Abordar el ruido del canal y mejorar la relación señal/ruido (SNR) para una transmisión de datos fiable.
- Demostrar un sistema de transmisión inalámbrica THz de alta capacidad y larga distancia.
Principales métodos:
- Se utilizó multiplexación por división de polarización (PDM) y técnicas de diversidad de antenas para aumentar la capacidad del sistema.
- Se empleó conformación duobinaria y detección de secuencias de máxima verosimilitud (MLSD) para abordar las limitaciones de ancho de banda de los componentes.
- Se propuso una red neuronal convolucional adaptativa no supervisada duobinaria (DB-UACNN) mejorada con modelo de mezcla gaussiana (GMM) para la mitigación del ruido del canal.
- Se demostró un sistema de transmisión inalámbrica THz asistido por fotónica de entrada múltiple, salida múltiple (MIMO) 2x2 a 300 GHz.
Principales resultados:
- La conformación duobinaria logró una ganancia de SNR de hasta 1,87 dB (polarización X) y 1,70 dB (polarización Y).
- La DB-UACNN mejorada con GMM proporcionó ganancias de SNR adicionales de hasta 2,59 dB (polarización X) y 2,63 dB (polarización Y).
- Se transmitió con éxito una tasa de datos de 100 Gbit/s a lo largo de 200 metros, cumpliendo el umbral de corrección de errores hacia adelante de decisión dura (HD-FEC) del 7%.
Conclusiones:
- El sistema integrado supera eficazmente los desafíos de la comunicación THz, mejorando tanto la capacidad como la distancia de transmisión.
- La DB-UACNN mejorada con GMM propuesta mejora significativamente la SNR y la resiliencia al ruido en sistemas duobinarios.
- Se logró una tasa de transmisión récord de 100 Gbit/s a lo largo de 200 m, allanando el camino para redes inalámbricas THz prácticas.
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