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Updated: May 24, 2026

Generation and Coherent Control of Pulsed Quantum Frequency Combs
Published on: June 8, 2018
High-performance monolithically integrated 120° downconverter with relaxed hardware constraints
P J Reyes-Iglesias1, I Molina-Fernández, A Moscoso-Mártir
1Departamento Ingeniería de Comunicaciones, ETSI Telecomunicación, Universidad de Málaga, 29071 Málaga, Spain. reyes@ic.uma.es
A novel 120° downconverter architecture offers improved calibration, extending dynamic range and bandwidth for coherent receivers. This advancement supports advanced modulation schemes in next-generation optical communication systems.
Area of Science:
- Electrical Engineering
- Optical Communications
- Signal Processing
Background:
- Coherent receivers are crucial for advanced optical communication systems.
- Conventional 90° downconverter architectures face limitations in dynamic range and bandwidth.
- Existing approaches in microwave and optical fields provide a foundation for new architectures.
Purpose of the Study:
- To propose and analyze a 120° downconverter architecture for coherent receivers.
- To compare the performance of the 120° downconverter with the conventional 90° architecture.
- To evaluate the suitability of the new architecture for next-generation optical communication systems.
Main Methods:
- Theoretical analysis and numerical evaluation of the 120° downconverter.
- Comparison of calibration procedures and performance metrics (dynamic range, bandwidth) against the 90° downconverter.
- Simulations of monolithically integrated downconverters.
Main Results:
- The 120° downconverter architecture demonstrates superior calibration capabilities.
- Full compensation of optical front-end imbalances is achieved.
- Extended dynamic range and broader operating bandwidth compared to the 90° counterpart.
Conclusions:
- The proposed 120° downconverter is a viable alternative for coherent receivers.
- It enables enhanced performance crucial for advanced modulation schemes like M-QAM.
- This technology supports the development of next-generation optical communication systems.
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