Tomoyoshi Kataoka

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A control method of current type PWM AC-to-DC converters which realize sinusoidal AC input current and unity power factor is discussed. In such a type of converter, an LC filter required on the AC side may cause a resonant problem especially in the transient condition. To overcome this problem, state feedback control is introduced, and a control strategy(More)
An Auto Bias Control (ABC) technique for the IQ-modulator of a flexible optical QAM transmitter is described. This technique can support various optical QAM signal formats with Nyquist filtering and electronic dispersion pre-compensation. 16, 32 and 64-QAM signals (21 Gbaud) are successfully generated, and all bias voltages are held to their optimum value(More)
We experimentally demonstrate the feasibility of a multi-degree colorless, directionless, and contentionless (C/D/C-less) ROADM node composed of high port count wavelength-selective switches and transponder aggregators using silica-based planar lightwave circuit technology. The experimental results show that the introduction of a C/D/C-less function to a(More)
A new control method for active power filters with voltage detection is proposed. The proposed control method is based on the real-time simulation of an LC filter accomplished by a digital signal processor. Thus the proposed active power filter acts equivalently as an LC filter whose circuit parameters, such as the resonant frequency and quality factor, can(More)
We propose arrayed optical amplifiers that share a single pump laser with the aim of realizing full-add/drop colorless, directionless, contentionless ROADM nodes and demonstrate its feasibility in experiments. The experimental results show that the fabricated arrayed optical amplifiers can be made to correspond properly to wavelength path reconfigurations(More)
Two-dimensional statistics and Q-penalty performance under the combination of two major impairments induced by polarization-dependent loss, namely level imbalance and loss of orthogonality between polarization-multiplexed tributaries, for a polarization-division-multiplexing digital coherent transmission at over 100-Gb/s are presented for the first time to(More)
This paper reports, for the first time, a 43-Gbit/s OTN interface prototype that implements more system functions than optical sending/reception, such as framing, scrambling/de-scrambling, client mapping, and supervisory functions, all with high performance. 1. Introduction Spectral efficiency in fiber bandwidth utilization is quite important for satisfying(More)
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