February 1, 2008
Four companies of Tokyo Cablevision Foundation (hereafter called TCV), LCV Corporation (hereafter called LCV) , KYOCERA COMMUNICATION SYSTEMS Co., Ltd. (hereafter called KCCS) and The Furukawa Electric Co., Ltd. (hereafter called Furukawa Electric) jointly started today, under a license issued by the Kanto Telecommunications Bureau of the Ministry of Internal Affairs and Communications, a series of experiments aimed at practical application of a relaying and delivery system, in which both multi-channel cable television broadcasting and cable high-speed Internet communications are transmitted using a radio relaying system. This is the first experiment in Japan on the bidirectional radio transmission of multi-channel cable television broadcasting and cable high-speed Internet communications.
This experiment is aimed at making the most use of radio communications in urban areas where electric poles are becoming a nuisance and still underground ducts are running short, and the 23-GHz band allotted to cable television broadcasters is used to implement radio link between the head office of TCV located in Okubo, Shinjuku-ku and a tenanted building located in Shinjuku 3-chome, Shinjuku-ku, which is approximately 1km apart.
While the 23-GHz band radio is currently utilized as a relying transmission means for analog cable television broadcasting, this experiment will help promote efficient utilization of radio transmission in the future by demonstrating its capability in transmitting digital broadcasting and bidirectional communications.
Background
Recent years have seen a rapid expansion of digitization and cable high-speed Internet communications thanks to technology innovation. However, in cases where cables are hard to be installed, i.e., in river crossing, detour in mountainous areas and between isolated islands, as well as in urban areas where electric poles are increasingly removed and still underground ducts are running short, service provision of cable television is often given up. It is expected that application of the proposed system in such areas leads to service area expansion.
In this experiment, TCV and LCV will provide transmission technology for cable television, and KCC and Furukawa Electric radio transmission technology and peripheral technologies.
Outline of Experiment
In this experiment, 32 channels (Note 1) of cable television video signals including pass-through transmission of terrestrial digital broadcasting and 3 channels bonding (Note 2) cable Internet signals based on Wideband DOCSIS (Note 3) are jointly transmitted, using the 23-GHz frequency band, from the TCV head office where the key station transmitter is installed to a tenanted building where the secondary station is located.
This experiment divides the 400-MHz bandwidth (23.20~23.60GHz) allotted for the 23-GHz band into a 300-MHz bandwidth (23.30~23.60GHz) for downlink and a 40-MHz bandwidth (23.20~23.24GHz) for uplink, thereby implementing bidirectional transmission.
During the experiment period, it is planned to carry out performance tests on bidirectional transmission including evaluation of radio transmission performance on a time of rainfall.
Schematics of Experiment Configuration
Glossary
(Note 1) 32 channels of cable television
Corresponding to 86 channels of broadcasting programs.Back to Main Content
(Note 2) 3 channels bonding
Bundling of multiple channels called “bonding”.
(Note 3) Wideband DOCSIS
A technology used in the cable Internet standards DOCSIS to realize high-speed transmission by bundling multiple channels.
For inquiries
| Tokyo Cablevision Foundation | Torii at General Affairs Department, at +81-3-5155-1361 |
| LCV Corporation | Negishi at Engineering Section, Engineering Division, at +81-266-53-3833 |
| KYOCERA COMMUNICATION SYSTEMS Co., Ltd. | Public Relation Department, at +81-3-5765-1503 |
| The Furukawa Electric Co., Ltd. | IR & Public Relations Department, at +81-3-3286-3050 |