NEC Develops Technology to Maximize Communications Speeds for LTE Femtocell Base Stations- Minimizes interference between base stations for smooth communications -

*** For immediate use May 10, 2012


Tokyo, May 10, 2012 - NEC Corporation (NEC; TSE: 6701) announced today the development of technologies for high speed, indoor mobile communications using LTE femtocell base stations that minimize radio signal interference between base stations by controlling the transmission power of radio signals. The adoption of these technologies enables transmission speeds to be maximized for smooth mobile communications both indoors and outdoors.

Recent years have seen the spread of LTE communications for high capacity, high speed wireless communications, and the growth of data transmission volumes is expected to continue. As a result, there is a growing need for the installation of femtocell base stations that cover small indoor areas, in addition to macrocell base stations that cover large outdoor areas. However, radio signal interference between both closely installed femtocell base stations and macrocell base stations is reducing transmission speeds for all base stations.

These newly developed technologies automatically adjust the transmission power of both femtocell base stations and the devices that connect to them. This is done in response to the transmission volume of the connecting device and the base station's surrounding environment. This enables high speed indoor and outdoor communications by curbing radio signal interference with macrocell base stations and allowing the high density installation of femtocell base stations.

Key characteristics of these technologies are as follows:
1) Controls transmission power of radio signals collectively for femtocell base stations and maximizes transmission speeds
NEC developed technologies that control the transmission power of radio signals for femtocell base stations in response to data transmission changes. This is collectively done for all femtocell base stations that are installed within the coverage area of a macrocell base station. As a result, when transmission volumes for femtocell base stations increase, the transmission power of radio signals is restrained, and transmission speeds are maintained by curbing the radio signal interference for devices that connect to macrocell base stations. Consequently, three times as many femtocell base stations can be deployed in an area than before. Moreover, the adoption of this software helps reduce power consumption since femtocell base stations require less transmission power when transmission volume is high. Furthermore, during times of low transmission volume, the transmission speeds of femtocell base stations have been improved by 1.2 times.

2) Controls transmission power for each femtocell base station and minimizes the radio signal influence of heavy users
These technologies identify base stations that are continually accessed by heavy users for carrying out heavy volumes of data transmission and they reduce the transmission power of radio signals. Furthermore, transmission power is increased for base stations of general users who carry out an average level of data transmission. This enables macrocell base station transmission speed reductions due to heavy users to be reduced by as much as 80%, as well as the high density installation of femtocell base stations. Additionally, transmission speeds are 1.3 times better for femtocell base stations serving the devices of general users.

3) Enables smooth communications through cooperation between femtocell base stations and macrocell base stations
NEC developed technologies for controlling the transmission power of each base station by collecting and automatically processing the data on radio signal interference power from femtocell base stations through devices within a macrocell base station's coverage area. As a result, radio signal interference can be curbed and smooth communications can be quickly realized from newly installed femtocell base stations since they can promptly begin operating once the previously adjusted settings for the degree of radio signal interference is entered.

Going forward, NEC aims to continue developing these technologies and to provide innovative new LTE femtocell base stations and operational management equipment.

[Attachment] Supplementary explanatory material

NEC Press Contacts (Japan):

Takehiko Kato
NEC Corporation
+81-3-3798-6511
t-kato@cj.jp.nec.com

Joseph Jasper
NEC Corporation
+81-3-3798-6511
j-jasper@ax.jp.nec.com