Press Releases

TOKYO, JAPAN, February 21, 2014 --- NTT DOCOMO, INC., a personalized mobile solutions provider for smarter living, announced today Japan's first field test of an active antenna system for mobile networks in which a 4 dB reduction in electrical loss compared to conventional antennas was demonstrated, a key development in power efficiency that promises someday to help enlarge the coverage range of base stations 1.7-fold.

The active antenna system for the field test was developed by Tokyo-based Nihon Dengyo Kosaku Co., Ltd. By demonstrating the active antenna system's capability to expand a base station's range of coverage, the field test points to the potential for more extensive mobile service in rural areas and faster recovery when rebuilding network infrastructure damaged by a natural disaster.

The new antenna integrates multiple antenna elements, each equipped with a small transceiver, which enables installment in confined spaces and assures continued coverage if one or more of the transceivers fails. Also, whereas electrical loss occurs in the connection between a separately located remote radio head (RRH) and a conventional antenna, as well as within the conventional antenna itself, integrating an RRH with each antenna element will result in more efficient operation.

Further, the active antenna system's compatibility with MIMO transmission technology should help to raise efficiency when deploying LTE-Advanced, and later 5G, network technologies.