Hình không dây băng rộng (BWA) các ứng dụng với một truy cập cố định. Hai ứng dụng chính của một BWA cố định không dây mới nhất dặm cho tốc độ dữ liệu cao và (cụ thể hơn) WiFi đường trục WiFi đường trục: NLOS WiMAX liên kết vô tuyến | Introduction to Broadband Wireless Access 9 Figure Broadband Wireless Access BWA applications with a fixed access. The two main applications of a fixed BWA are wireless last-mile for high data rate and more specifically WiFi back-hauling case when it is no longer a CPE but a card installed in some laptop. A nomadic access shown in Figure is an access where the user or the subscriber may move in a limited area . in an apartment or a small campus. This area is the one covered by a BS. Whenever the user moves out of the zone the communication or the session is interrupted. A typical example wireless terminal Figure Nomadic or portable BWA 10 WiMAX Technology for Broadband Wireless Access of a portable access is WLAN WiFi use in its first versions and where a session is interrupted when the terminal gets out of a WLAN coverage even if it enters a zone covered by another WLAN . in two neighbouring companies. The nomadic access is very useful in some cases such as campuses company areas compounds etc. It can be observed that due to this position which is not fixed the link between the BS and the SS has to be NLOS it can be LOS only in the case of fixed CPEs theoretically . A nomadic access is also sometimes known as a wireless access. The final expected step of WiMAX is a mobile access. The difference between wireless and mobile will now be discussed. Wireless is Not Mobile Different scenarios of mobility can be considered. The most simple one is when two neighbouring BSs belong to the same operator. Hence the same billing system and customer care apply to the two BSs. In this case a user moving from one cell to a neighbouring one has to start the session again. This feature is nomadicity rather than mobility. Mobility or full mobility is the scenario where the session is not interrupted whether this is a data session a voice communication over IP or not a video transmission etc. The distinction is made between wireless but
