tailieunhanh - Wireless data technologies reference handbook phần 4

Ngoài ra, nó giới thiệu qua-không khí kích hoạt dịch vụ và lập trình. • IS-136B bao gồm một phạm vi mới của dịch vụ bao gồm cả tin nhắn SMS truyền hình, dữ liệu gói và những người khác. Nó có thể được khó để nhận ra điều này, nhưng nó thực sự là không phải tất cả những gì lâu trước khi chỉ là một điện thoại đồng bằng cũ là một thứ xa xỉ. | 56 IMODE NTT-DoCoMo and Hewlett-Packard have announced that the two companies are jointly developing technologies for 4G wireless communications. They have named the technology platform MOTO-Media. Initially DoCoMo planned to introduce 4G services around 2010. Recently DoCoMo announced plans to introduce 4G services from 2006 . four years earlier than previously planned. 4G Data Rates in Japan At present the 2G iMode data rates in Japan are up to sec but are usually a lot slower and kbps for 504i handsets since May 2002 . For 3G FOMA data rates are at present around 200 kbps download and 64 kbps upload and may in the future be upgraded to 2 Mbit sec. For 4G data rates up to 20 Megabytes per second are planned. This is about 2000 times faster than present mobile data rates and about 10 times faster than top transmission rates planned in the final build out of 3G broadband mobile. It is about 10-20 times faster than standard ASDL services which are being introduced for Internet connections over traditional copper cables at this time. Of course it is impossible to predict technology developments and the evolution of culture and customer needs. 4G in principle will allow high-quality smooth video transmission. Conclusion Therefore iMode is a combination of available technologies. Although CDMA and C-HTML are not distinguished technologies iMode proved that these technologies were enough to satisfy the needs of million customers. They want a quick continuous connection to the Internet from anywhere anytime at reasonable costs though transmission speed is lower than their PC Internet connections. Moreover iMode is changing the information system of existing businesses. Customers no longer want to call somebody in an office. They need a direct contact to their sales representative and customized information that they can read with their smart phones. iMode demands that information managers change their system from the CEO s secretary to .