Minutes of Expert Online-Jun.29,2001
Mr.Huang Chenhong

Mr. Huang Chenhong
Director of Strategic Technology&Network Planing Department,Nortel Networks

Q: If Frame is too long, mobility will result in the propagation change, that is to say, TDD does not keep the symmetry of DL and UL.
A: UL and DL symmetry depends primarily upon the frequency. So for TDD, the symmetry between DL and UL can be kept to a large degree. Of course in fast mobility case, propagation symmetry could change. How much impact on capacity due to some degree of asymmetry is to be verified.

Q: what progress is Nortel Network in the aspects of TD-SCDMA?
A: TD-SCDMA forum is one of the groups that promote TD-SCDMA, and Nortel has been a founding member of that organization. We have been very supportive to the TD-SCDMA standardization process, both in 3GPP and ITU. Furthermore we are working with domestic vendors such as Datang with detailed technical exchanges

Q: Will TD-SCDMA cooperate and competition with Las TDD ?
A: We think LAS can be complimentary to TD-SCDMA. LAS has claimed that if you use LAS codes for TD-SCDMA, you may realize more capacity gains. This of course will have to be verified independently. If this is indeed true then TD-SCDMA can benefit from LAS.

Q: Dr. Huang, TSM Standard is only the temporary one for the evolution from TD-SCDMA to GSM. What is your view?
A: Personally I do not think TSM will have a future in the market place. Let me explain why.
First, TSM is not what ITU and 3GPP stands for. TD-SCDMA should be a 3G standard, not a 2G extension; Secondly, service providers do not like TSM for the very reason that TSM is not an international standard and it messes up with service provider's network evolution plans; Thirdly, TSM can NOT deploy any 3G services and applications, so what is the purpose; Fourthly, no service providers accept TSM, yet; Last but not least, if you go TSM then you lose the evolution path as an international standard, therefore you are isolated. Look at the history of wireless - when you are isolated you do not have a future.

Q: Dr. Huang, No difference between WCDMA CN and TD-SCDMA CN? A£º From standards perspective, yes, there is no difference between FDD and TDD for Iu. However, as expected, Iub and Iur do have differences, although the differences are not very significant.

Q: Dr. Huang, what is DO and DV?
A: DO and DV are the concepts of 1xRTT or cdma2000 evolution. The first step of the cdma2000 evolution is called 1xEV-DO, which means data only. It can provide very efficient high speed data services. The second step is called 1xEV-DV, meaning for both voice and data.

Q: If so, this will not meet future frequency handover between TD-SCDMA and GSM ?
A: Handover between GSM and TD-SCDMA is a separate question. A hard handover can happen, no matter what the guard band is. However, my personal view is that handover is of secondary concerns.

Q: What did Nortel do for TD-SCDMA? Can be more specific?
A: What Nortel has been doing for TD-SCDMA is the following: 1) we have followed and studied TD-SCDMA since the very beginning; 2) we supported very strongly in 3GPP and ITU standards process for the standardization of TD-SCDMA; and 3) we are working very closely with Datang in discussing some technical details of TD-SCDMA.

Q: Dr. Huang, now you are talking about handset. Maybe you know something more about handset over world. Please show us !
A: As you know, Nortel is not a handset vendor. So we are also very curious about the status of TD-SCDMA handset development. Maybe we can ask Datang or Siemens next time. But you are right, handsets are one of the determining issues for TD-SCDMA commercialization. Just like any other technology in wireless, without handsets you can't build a market. I would like to see more vendors working on handsets and publish their product schedules.

Q: Is there any bully to 3G by 802.11b?
A: IEEE802.11 and 3G are serving two different markets. Wireless LAN (802.11) is targeting inbuilding and corporate environment, while 3G is serving users for wide area mobilities.
So IEEE 802.11 and 3G will be complimentary, not necessary competitive. That is also why it is very important for TD-SCDMA to be able to form its own macro networks. Otherwise it falls into the same category of IEEE802.11

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