"NTT DoCoMo Inc. is nearing the countdown to launch its IMT-2000 service, a global standard next-generation mobile communication system, in Japan.
"The company, which has more than 10 million i-mode cellular phone subscribers, is due to start the new service at the end of May 2001. NTT DoCoMo claims it will be the world's first such service, and thus will draw lots of attention.
"Nikkei Communications: How do you describe the IMT-2000 service?
"Tachikawa: At an early stage, phones used for the service will come in four types: (1) a basic tool as a cellular phone, (2) a visual telephone system, (3) a PC-linked private data terminal, and (4) a car-navigation system. However, I can easily envision that a host of advanced models of IMT-2000 terminals will emerge as the service goes on.
"Q: What kinds of applications do you plan to provide in the new service?
"Tachikawa: We are planning to devote ourselves to developing a variety of devices with attractive specifications. This means that how to use terminals is up to users. I believe that if customers begin using them in a broader fashion, we will have various ideas for uses of the terminals.
"Q: How much will the IMT-2000 service cost?
"Tachikawa: We are now studying the pricing strategy, but our final decision on prices will be made by May 2001. However, what I can promise now is the price for audio transmission via IMT-2000 service will be evenly matched with that via the existing personal digital cellular (PDC)-formatted phone.
"Q: What will be the price for data communications via IMT-2000 service?
"Tachikawa: We plan to lower the unit price per bit, hoping to tap demand for high-speed data transmission among users.
"Q: Do you intend to charge IMT-2000 users a fixed amount?
"Tachikawa: Logically speaking, it is impossible to do that. Wireless terminal users are sharing a limited band of airwaves, and each wire terminal subscriber is allocated a circuit one-by-one.
"Q: Can users of IMT-2000 use the network as a means of broadband access to the Internet?
"Tachikawa: They can, however, there is a risk that if everybody is to use the IMT-2000-based Internet connection full-time under a fixed phone charge system, it will trigger a chronic traffic jam, because the frequency band will be always occupied by a limited number of users. Rather than introducing a flat-rate system, it is better to set the phone rate at a low level.
"Q: When do you think the data traffic will exceed the voice traffic in a cellular phone system?
"Tachikawa: I have a hunch that voice communication and non-voice (data) use will be evenly matched in 2005, and that the majority of data traffic will come from IMT-2000 users. Although NTT DoCoMo has recently released a survey finding that an estimated 80 million terminals will be in use for the new service as of 2010, the figure stands for voice use alone. Combined with non-voice terminals, such as a PC card and a car navigation device, the total number may swell to three or four times the 80 million.
"Q: Your company has a projection that the initial number of IMT-2000 subscribers may be 10s of thousands at the time the service starts, but isn't that an underestimation?
"Tachikawa: At the end of May 2001, we will start the service in the Tokyo Metropolitan area (23-ward area), Yokohama and Kawasaki. After that, the service area will be expanded to Osaka and Nagoya in December 2001. However, we expect that only a few percent of i-mode users, who dwell in those areas, will shift to the new service. And I am afraid the quality of voice will not be substantially improved even if they move to the new service.
"Q: For the IMT-2000 service, the J-Phone group and new "KDDI" are believed to be competitors. Which one, however, do you think is the most competitive?
"Tachikawa: I cannot answer the question because they have different introduction periods and platform. To compete with J-Phone, for example, which will employ the W-CDMA technology, the same as ours, it is necessary to make our service more convenient and friendly to customers than J-Phone. KDDI will start a new service with a different technology and at a different time. We will then be in competition when all the players are out there.
"Q: KDDI has said its 800MHz 144kbps service will be extended nationwide by the end of 2002. Is this posing a threat to NTT DoCoMo?
"Tachikawa: I wonder if KDDI can attain its initial goal as scheduled. Will it pay? I don't know.
"Q: In Europe, before introducing the W-CDMA third-generation (3G) technology, there is a possibility of releasing "2.5G" communication technology. This might affect the roaming service, a main feature of the IMT-2000 service.
"Tachikawa: To solve the problem, we are now considering introducing a dual-mode terminal.
"Q: Do you intend to introduce a dual-mode terminal to make roaming via overseas carriers possible?
"Tachikawa: Absolutely. If a dual-mode cellular phone with two or more wireless transmission standards is made available to users, they do not need to worry about the difference when using their handset, clearing the way to do away with a standard for the fourth-generation cellular phone system.
"Q: Is there a possibility for NTT DoCoMo to develop an IMT-2000/PDC dual-mode phone in Japan?
"Tachikawa: I think it is unavoidable to do so. It is likely that there will be strong demand for IMT-2000/PDC dual-mode phones among users.