Direct-sequence spread spectrum uses a small number of fixed, wide channels that can support complex modulation schemes and somewhat scalable data rates. Each channel is 22 MHz wide—a much wider bandwidth compared with the maximum supported 11-Mbps data rate, but wide enough to augment the data by spreading it out and making it more resilient to disruption. In the 2.4-GHz band where DSSS is used, there are 14 possible channels, but only 3 of them that do not overlap. Figure 1-26 shows how channels 1, 6, and 11 are normally used.


Figure 1-26 Example Nonoverlapping Channels Used for DSSS.

DSSS transmits data in a serial stream, where each ...

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