This section details the techniques of modulation and encoding in IEEE 802.11 protocol. These techniques are not unique to 802.11; they also apply to 802.15 protocols and, as we will see, to cellular protocols as well. The methods of frequency hopping, modulation, and phase-shift keying are fundamental methods that should be understood by an architect as different techniques balance range, interference, and throughput.
Digital data transmitted by an RF signal must be transformed into analog. This occurs at the PHY no matter what RF signal is being described (Bluetooth, Zigbee, 802.11, and so on). An analog carrier signal will be modulated by a discrete digital signal. This forms what is called ...
