Minutes of Expert Online-Nov.13,2001
Mr.You Xiaohu,Professor of South-east University

Mr. You Xiaohu
Mr. You Xiaohu was born in August 1962 and obtained the Ph. Doctor degree of Signal, Circuit and System in South-east University in 1988. At the present, Mr. You is the professor of the National Key Mobile Telecommunication Lab, the doctor supervisor, the Changjiang Scholar professor and the Director of the Wireless Engineering Department. Besides, Mr. You is the Middle-aged Experts with prominent contribution at the national level, the winner of the National Excellent Youth Fund and the candidate of the Trans- century Youth Expert selected by the National Education Committee. Mr. You has been engaged in the R&D and teaching work of mobile telecommunication and signal processing for a long time within which he undertook dozens of national projects related to mobile telecommunication. Mr. You has published several papers in IEEE Transactions that have been cited near one hundred times. In addition, he has published two books in Chinese and English. In 1999, Mr. You became the head of the General Group of National 3G System R&D Project, responsible for the R&D of 3G systems.

Q: Any clue about the relationship of UMTS TDD and TD-SCDMA?
A: Both UMTS TDD and TD-SCDMA are TDD-based, and the generic technologies are the same. The main differences are the frame structure and chip-rate.

Q: WHO ARE DEVELOPING UMTS TDD?
A: Currently nobody.

Q: Can SDR used for TD-SCDMA at the first phase?
A: SDR is a generic technology, and can be used for any kind of systems.

Q: Any analysis has been done to show the coexistence of WCDMA with TD-SCDMA? Which bandwidth is preferred?
A: Yes. Several companies have published their theoretic and simulation results. But it should be verified via field trial.

Q: Who is going to manufacture TD-SCDMA equipment in China or overseas?
A: Datang Mobile, Siemens and some others.

Q: Besides TD-SCDMA and WCDMA in 3GPP, how do you think the strength of UTRA TDD?
A: Currently nobody is concerned about the UTRA TDD.

Q: Does anyone know the reason why UTRA TDD is not under developing, or it is difficult to develop or TD-SCDMA is better?
A: What is important is that the market trend. The market for TDD is not clear in European countries.

Q: Some experts say that LAS-CDMA as FalunGong can solve all wireless problem by a single code. Is that true?
A: Solving all problems by a single technique is impossible.

Q: Why do you always discuss LAS-CDMA?
A: Why? Is this not TD-SCDMA forum?!

Q: How do you think of the Xi'an Datang has become one of the 18 handset manufactores? is it a good news to catt?
A: xi'an Datang is a very good company for infrastructure manufacturing. They don't have much experience in handsetＮfrom this point of view, they should work hard for both R&D and marketing promotion。

Q: If TD-SCDMA is really profitable, why other companies don't join the development effort?
A: People don't like waiting longer.

Q: Similar to Qualcomm CDMA, if there's no manufacturer to manufacture the equipment, where shall TD-SCDMA tech be output? Only between Siemens and CATT?
A: There is a risk for TD-SCDMA because of technology maturity. If we can succeed in developing TD-SCDMA system, we do believe it's profitable

Q: Do you think Wireless LAN will compete TD-SCDMA if some key problems are solved?
A: No, I don't think Wireless LAN can meet the requirement of high density applications。The TD-SCDMA can provide guaranteed QoS, but wireless LAN can not. if there are too many users for wireless LAN, the spectrum efficiency will be very low。

Q: If Europe use some new tech for already auctioned TDD spectrum before TD-SCDMA is pushed to the market, what shall we do?
A: Yes, we should make TD-SCDMA commercialized available as early as possible. If TD-SCDMA is too late, then it could be very difficult. People can not wait for the new technology for a long time。

Q: How much work should be done to move from TSM to 3GPP standard, especially at the protocol stack?
A: Yes, we should work hard for the protocol stack standardization. currently we only have the first version of TD-SCDMA standard provided by 3GPP.。we should make the standard mature as early as possible.。

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