Geekzone: technology news, blogs, forums
Guest
Welcome Guest.
You haven't logged in yet. If you don't have an account you can register now.
NTT DoCoMo achieves 1Gbps in 4G field experiment
Posted on 23-Jun-2005 20:36 | Tags Filed under: News



NTT DoCoMo, Inc. achieved 1Gbps real-time packet transmission in the downlink while moving at about 20km/h in a field experiment on 4G radio access. 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.

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.

The company 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.







comments powered by Disqus


Trending now »

Hot discussions in our forums right now:

Bombing at Manchester concert, 19 dead
Created by Rikkitic, last reply by Rikkitic on 27-May-2017 12:55 (161 replies)
Pages... 9 10 11


NZ Herald - Internet providers have backdoor access to customers' modems
Created by RunningMan, last reply by michaelmurfy on 27-May-2017 19:23 (27 replies)
Pages... 2


Father banned from watching daughter's netball game: what you think of this?
Created by Rikkitic, last reply by frankv on 25-May-2017 16:29 (136 replies)
Pages... 8 9 10


Tailgaters?
Created by Linuxluver, last reply by reg52nz on 25-May-2017 16:29 (113 replies)
Pages... 6 7 8


The President Of The USA: Donald Trump
Created by TimA, last reply by freitasm on 27-May-2017 19:32 (4367 replies)
Pages... 290 291 292


Tax Cuts
Created by tdgeek, last reply by mattwnz on 27-May-2017 18:47 (62 replies)
Pages... 3 4 5


Tipping? Please no!
Created by BlueShift, last reply by cddt on 27-May-2017 10:10 (104 replies)
Pages... 5 6 7


Variable speeds on Fibre Max
Created by kapitikarl, last reply by nutsterrt on 27-May-2017 15:20 (45 replies)
Pages... 2 3