NTT DoCoMo Achieves 1Gbps Packet Transmission in 4G Field Experiment

Jun 23, 2005

NTT DoCoMo, Inc. announced today that it achieved 1Gbps real-time packet transmission in the downlink at the moving speed of about 20km/h in a field experiment on fourth-generation (4G) radio access. The experiment took place in Yokosuka, Kanagawa Prefecture on May 9, 2005.

This is the latest achievement in DoCoMo's ongoing development of key radio access technology for 4G mobile communications.

The 1Gbps real-time packet transmission was realized through Variable Spreading Factor-Spread Orthogonal Frequency Division Multiplexing (VSF-Spread OFDM) radio access and 4-by-4 Multiple-Input-Multiple-Output (MIMO) multiplexing using "adaptive selection of surviving symbol replica candidate" (ASESS) based on Maximum Likelihood Detection with QR decomposition and the M-algorithm (QRM-MLD), which was developed by DoCoMo. By using the new algorithm, DoCoMo was able to reduce the large computational complexity of the original MLD method while maintaining almost the same achievable throughput performance. Frequency spectrum efficiency, which is expressed as information bits per second per Hertz, is 10 bits per second per Hertz, about 20 times that of 3G radio networks' spectrum efficiency.

During an earlier trial in July 2003, DoCoMo achieved 100Mbps and 20Mbps data rate transmission in the downlink and uplink, respectively, in outdoor environments using the same 100MHz bandwidth.

DoCoMo will continue to conduct field trials as part of its program to develop a 4G global standard in cooperation with the International Telecommunication Union Radiocommunication Sector. The telecommunications council of Japan's Ministry of Internal Affairs and Communications aims to see 4G services commercialized in the country by 2010.

Explore further: Amazon launches one-hour shipping in Manhattan

add to favorites email to friend print save as pdf

Related Stories

Field experiments of 4G LTE-advanced system underway

Feb 07, 2011

NTT DOCOMO announced today that on January 27 it was pre-licensed by the Kanto Bureau of Telecommunications of the Ministry of Internal Affairs and Communications for field experiments of LTE-Advanced, a true fourth-generation ...

Recommended for you

Sony hacking fallout puts all companies on alert

8 hours ago

Companies across the globe are on high alert to tighten up network security to avoid being the next company brought to its knees by hackers like those that executed the dramatic cyberattack against Sony Pictures ...

Ear-check via phone can ease path to diagnosis

10 hours ago

Ear infections are common in babies and young children. That it is a frequent reason for young children's visit to doctors comes as no consolation for the parents of babies tugging at their ears and crying ...

Timeline of the Sony Pictures Entertainment hack

10 hours ago

It's been four weeks since hackers calling themselves Guardians of Peace began their cyberterrorism campaign against Sony Pictures Entertainment. In that time thousands of executive emails and other documents ...

Two more former Sony workers sue over data breach

10 hours ago

Two more former employees of Sony Pictures Entertainment are suing the company over the massive data breach in which their personal and financial information was stolen and posted online.

Files of more than 40,000 federal workers breached (Update)

11 hours ago

The computer files of more than 40,000 federal workers may have been compromised by a cyberattack at federal contractor KeyPoint Government Solutions, the second breach this year at a major firm handling national security ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.