2011 Fiscal Year Final Research Report

Study on Ultra-wideband Measurements of Optical Electric Fields for Optical Fiber Communications

Research Project

Project/Area Number	22656090
Research Category	Grant-in-Aid for Challenging Exploratory Research
Allocation Type	Single-year Grants
Research Field	Measurement engineering
Research Institution	The University of Tokyo
Principal Investigator	KIKUCHI Kazuro 東京大学, 大学院・工学系研究科, 教授 (50134458)
Project Period (FY)	2010 – 2011
Keywords	計測機器
Research Abstract	We have studied the method for measuring the optical electric field of single-channel 10-Gsymbol/s QPSK signals, where we first obtain spectral amplitudes and phases by separating the signal bandwidth and then reconstruct them in the time domain. We measure signal complex amplitudes within the separated bandwidths in parallel using two phase-diversity homodyne receivers, where two LOs are phase-locked. Next, these temporal waveforms are converted into the frequency domain, where two spectral waveforms are continuously connected. Then, such signal is successfully converted into the time domain and the QPSK signal is reconstructed. Waveform distortion of the reconstructed signal is generated from insufficient filtering characteristics, but can be compensated for by using signal equalization techniques.

(5 results)