Kích thước cửa sổ cho Thiết lập và ứng cử viên đăng nhập Set. Trường này chuyển tải kích thước cửa sổ tìm kiếm (phạm vi của hiệu số PN) được sử dụng bởi các trạm di động để tìm kiếm cho các thành phần đa đường củaTìm kiếm Window Kích thước Set còn lại. lĩnh vực này | Part IV 3G Systems 2002 by CRC Press LLC 7 IMT-2000 Introduction The conception of third-generation 3G wireless systems is embodied by the International Mobile Telecommunications-2000 IMT-2000 . IMT-2000 standards and specifications have been developed by various standards organizations worldwide under the auspices of the International Telecommunications Union ITU . 3G telecommunication services target both mobile and fixed users with the access provided via a wireless link. A wide and ambitious range of user sectors radio technology radio coverage and user equipment is covered by IMT-2000. In essence a 3G system must provide for Multimedia services in circuit-mode and packet-mode operations User sectors such as private public business residential local loop and others Terrestrial-based and satellite-based networks Personal pocket vehicle-mounted or any other special terminal Moreover global roaming and virtual home environment VHE are supported by 3G systems. Global roaming capability allows users to roam across different wireless networks and the VHE characteristic provides roamers with the set of services and features of their home network. The key features of IMT-2000 as specified in Reference 1 include High degree of commonality of design worldwide Compatibility of services within IMT-2000 and fixed networks High quality Small terminal for worldwide use Capability for multimedia applications and wide range of services and terminals o 2002 by CRC Press LLC IMT-2000 may be implemented as a stand-alone network or as an integral part of the fixed networks. In the first case gateways and interfacing units must be provided so that internetworking operations can be supported. Note that this has been the standard solution for the internetworking operation between conventional public land mobile and fixed networks and also between conventional mobile networks of different technologies. In the second case the fixed network must accommodate the functionality specific
