Enhanced monolithically integrated coherent 120° downconverter with high fabrication yield.

Conventional monolithically integrated 90° downconverter suffers from hardware-induced non-linear constellation distortion, which gets worse far away from the central wavelength or when fabrication errors are taken into account. To overcome these problems, a 120° monolithically integrated downconverter with full compensation of hardware non-idealities has been proposed. It is numerically demonstrated that, in a realistic scenario exposed to the combined effects of fabrication tolerances and limited ADC resolution, this approach exhibits a significantly better signal dynamic range and a remarkable improvement of fabrication yield.

[1]  Peter J. Winzer,et al.  Colorless coherent receiver using 3×3 coupler hybrids and single-ended detection , 2011, 2011 37th European Conference and Exhibition on Optical Communication.

[2]  T Pfau,et al.  Coherent optical communication: towards realtime systems at 40 Gbit/s and beyond. , 2008, Optics express.

[3]  S.J. Savory,et al.  Compensation of Quadrature Imbalance in an Optical QPSK Coherent Receiver , 2008, IEEE Photonics Technology Letters.

[4]  Vincent Houtsma,et al.  Manufacturable monolithically integrated InP dual-port coherent receiver for 100G PDM-QPSK applications , 2011, 2011 Optical Fiber Communication Conference and Exposition and the National Fiber Optic Engineers Conference.

[5]  M. Nakazawa.  Ultrafast and high-spectral-density optical communications systems , 2011, CLEO: 2011 - Laser Science to Photonic Applications.

[6]  Electro-optics.  Conference on lasers and electro-optics (CLEO) , 2003 .

[7]  M. Smit,et al.  Optical bandwidth and fabrication tolerances of multimode interference couplers , 1994 .

[8]  Alejandro Ortega-Moñux,et al.  Signal Constellation Distortion and Ber Degradation Due to Hardware Impairments in Six-Port Receivers with Analog I/Q Generation , 2011 .

[9]  R. Noe,et al.  Hardware-Efficient Coherent Digital Receiver Concept With Feedforward Carrier Recovery for $M$ -QAM Constellations , 2009, Journal of Lightwave Technology.

[10]  P J Reyes-Iglesias,et al.  High-performance monolithically integrated 120° downconverter with relaxed hardware constraints. , 2012, Optics express.

[11]  Pablo Perez-Lara,et al.  Broadband Five-Port Direct Receiver Based on Low-Pass and High-Pass Phase Shifters , 2010, IEEE Transactions on Microwave Theory and Techniques.

[12]  Renato G. Bosisio,et al.  An alternative explicit six-port matrix calibration formalism using five standards , 1988 .