Station (BS) and one or more subscribe station (SS), depending on the implementation of the topology. Therefore, the BS provides Point to Point (PTP) service or Point to Multi point (PMP) service in order to serve multiple SSs. BSs provide connectivity to core networks. The SS can be a roof mounted or wall mounted customer premises equipment (CPE) or a stand alone hand held device like Mobile phone, personal digital assistant (PDA) or peripheral component interconnect (PCI) card for PC or Laptop. In case of a outside CPE, the users inside the building are connected to a conventional network like Ethernet Local Area Network (IEEE 802.3 for LAN) or Wireless LAN (IEEE 802.11b/g for WAN) which have access to the CPE. A group of cells can be grouped together to form a network, where BSs are connected through a core network, as shown in Figure 2.2. The IEEE 802.16 network also support mesh topology, where SSs are able to communicate among them selves without the need of a BS .
Figure 2.2: A typical IEEE 802.16 Network
BSs typically employ one or more wide beam antennas that may be partitioned into several smaller sectors, where all sectors sum to a complete 360 degree coverage. CPEs typically employ highly directional antennas that are pointed towards the BS. Depending on the need, IEEE 802.16 network can be deployed in different forms.