Fujitsu and NTT DoCoMo Conducts 3G LTE Field Testing
Fujitsu and NTT DoCoMo Conducts 3G LTE Field Testing
16th March, 2009
Japan : Fujitsu and NTT DOCOMO have conducted successful field testing for Long-term Evolution (LTE(1)), a core technology standard for high-speed wireless communications, using 4x4 MIMO(2).
The testing took place in the Special Ubiquitous Zone, an area of the northern Japanese city of Sapporo in Hokkaido, designated by the Ministry of Internal Affairs and Communications in 2008 as a wireless communications testing area, and used prototypes of the wireless LTE base stations developed jointly by NTT DOCOMO, Fujitsu and Fujitsu Laboratories which, with the use of MIMO technology, resulted in high-speed wireless transmissions in the range of 120 Mbps (using 10 MHz bandwidth) in Sapporo's urban environment.
LTE, sometimes referred to as the 3.9G wireless standard, is a standard for wireless communications that enables broadband communications for mobile phones. It is an international standard created by the standard-setting organization 3GPP(3) and is intended to produce dramatic improvements in wireless performance, including faster, higher-capacity data communications, reduced connection lag times, and more efficient bandwidth frequency utilization.
Fujitsu and Fujitsu Laboratories were selected by NTT DOCOMO in 2006 to be the developer and manufacturer of their wireless LTE base stations. Since then, they have worked together with NTT DOCOMO to develop these technologies using 4x4 MIMO, which increases speed and capacity in both transmitting base stations and receiving mobile stations, and the three companies have performed successful tests of a prototype three-sector LTE base station that has a transmission capacity of 300 Mbps per sector on the downlink (20 MHz band).
The field testing involved LTE transmissions using NTT DOCOMO test stations in Sapporo's urban environment, assessing the throughput characteristics of 4x4 pre-coding MIMO(4) on the downlink and confirming that a maximum of 120 Mbps (using 10 MHz bandwidth) could be attained over a measured course. This would be equivalent to 240 Mbps throughput using the 20 MHz maximum bandwidth that LTE allows. These tests revealed that the adaptive switching used in MIMO multiplexing was effective in achieving stable throughput in outdoor carrier environments.
Through transmission speeds measuring approximately 35 times that of 3.5G (7.2Mbps) and 2.5 times that of fixed optical fiber lines (100Mbps), wireless LTE transmission of large volumes of data used in high-definition videos, as well as in business and everyday life, is now possible.
The results will contribute to Fujitsu's ongoing development of wireless base stations, as well as core network systems, handset technology, and the total LTE commercial network.
Partial results from these tests will be presented jointly by Fujitsu, Fujitsu Laboratories, and NTT DOCOMO at the general meeting of the Institute of Electronics, Information, and Communications Engineers (IEICE), on March 17 at Ehime University in Japan.
Glossary & Notes
- 1 LTE:
- Long-Term Evolution. The name for the wireless communications standard devised by members of 3GPP, including Fujitsu and NTT DOCOMO.
- 2 4x4 MIMO:
- Multiple-input, multiple-output. MIMO, a core technology underlying LTE, is a spatial multiplexing technology that uses multiple antennas transmitting/receiving different signals on the same frequency. The 4x4 MIMO which employs four antennae at both the transmitting base stations and receiving mobile station, can dramatically increase wireless communications speeds without increasing frequency width.
- 3 3GPP:
- 3rd Generation Partnership Project. The partnership project that produced the detailed specification for IMT-2000 W-CDMA. Standards-setting organizations from around the world developed a common standard to be used in all nations and regions in the form of the standard developed under 3GPP. Includes many companies and organizations as members, including the world's leading mobile carriers.
- 4 Pre-coding MIMO:
- The MIMO transmission method adopted as a standard by 3GPP. A technology where the receiving handset sends feedback regarding its reception characteristics to the wireless base station to optimize MIMO transmissions.