Vol.4 No.2 2011
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Research paper : Demonstration of optical communication network for ultra high-definition image transmission (J. Kurumida et al.)−113−Synthesiology - English edition Vol.4 No.2 (2011) set, it was connected to NICT since the west terminal of JGN2plus was located at NICT (Koganei). This range was set up as the network. The distance between these points was about 42.7 km, and the round trip distance was 105 km from Akihabara. The demo site was located in two places, NICT (Koganei) and AIST (Akihabara). This distance was suitable as a network model connecting the area within a city. The major issue was to establish the communication by the 43 Gb/s optical modulation signal, the fastest signal used in the demo. Therefore, we planned the complete compensation for the effect of signal degradation by wavelength dispersion in the 105 km of optical fiber, using the high-speed autonomous control tunable dispersion compensator that we developed. However, since the transmission loss at 0.2 dB/km or more in the optical fiber and the loss due to optical connectors and parts were unknown, it was uncertain whether the optical S/N ratio would fall within the acceptable range of the receiver. Therefore, we prepared a backup plan to decrease the difficulty of the transmission for the video distribution demo based on the simplification of the topology.The site of the demo experiment was set up on one of the floors of AIST Akihabara, as shown in Fig. 4. The hardware was placed in groups by elemental technologies. Although it was compared with Fig. 3, in practice, the design in Fig. 4 was completed first. As a result of giving priority to the size of the device and convenience of connection in a limited space, the layout was determined without inconvenience. As the actual hardware was prepared as in Fig. 4, the devices and equipment were connected by each function block. In building the experimental system, the connection process was the most important, and misconnection or major communication line loss were not acceptable. The connections were done accurately and at appropriate signal level using a switch port table. 5.2 Video distribution experimentOne of the highlights of the demo experiment was to see whether the path communication for 43 Gb/s, the fastest optical modulation signal, was possible over the 105 km transmission distance. This is the communication path shown as a red line in Fig. 3. When the path was tested by bit error rate tester, it did not become error free even when the optical signal intensity was raised, and we were concerned about the disturbances or interruptions in the SHV video. However, when the actual connection was made with the receiver with the appropriate optical power, the communication was established due to the signal error correction function of the device. Although the signal error correction function was nothing special, whether the 43 Gb/s path at transmission Fig. 3 Schematic diagram of the joint connection experiment for the optical networkDemo 1Demo 2Demo 3To server D 8K image A 8K image BStorage resource managerPath set-upStorage set-upVideo transfer controlSHV deliveryLAN-SAN system technologyNEDO_LAN-SAN technologyPath set-up/release request from outsideFile transferPath set-up/release requestPermissionFile transferTV conference (HD)TV conference (HD)Path set-up processPathFile serverPacketOtemachiKoganeiServer B (HD)Silicon photonics switchViewer D (SHV)Server C (SHV)To server AParametric tunable dispersion compensatorHigh-performance highly nonlinear fiberDynamic wavelength resource managementParametric arbitrary wavelength converterNetwork resource managerHigh-speed wavelength tunable laser modulewavelength selective switch for Transponder aggregatorNetwork storage integrated resource managementAkihabaraViewer E (SHV)Viewer B (HD)To contents server SViewer A-2 (HD)Viewer A-1 (HD)Viewer C (HD)(thermooptic effect)(plasma effect)Optical Packet and Circuit Integrated Networki

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