Summary

The use of Spread Spectrum is especially important as it allows many more users to occupy the band at any given time and place than if they were all static on separate frequencies. With any radio system, one of the greatest limitations is available bandwidth, and so the ability to have many users operate simultaneously in a given environment is critical for the successful deployment of WLAN.

The application of Infrared is as a docking function and in applications in which the power available is extremely limited, such as a pager or PDA.

There are two methods of Spread Spectrum modulation: Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread Spectrum (FHSS).

IEEE 802.11 appears to higher layers [Logical Link Control (LLC)] as an IEEE 802 LAN, which requires that the IEEE 802.11 network handle station mobility within the MAC sublayer and meets the reliability assumptions that LLC makes about the lower layers.

In Bluetooth standard the HCI uses command packets for the host to control the module. The module uses event packets to inform the host of changes in the lower layers. The data packets are used to pass voice and data between host and module. The transport layers carry HCI packets.

Bluetooth can be used as a bearer layer in WAP architecture. A WAP server can be preconfigured with the Bluetooth device address of a WAP server in range, or a WAP client can find it by conducting an inquiry and then use service discovery to find a WAP server.

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