Planet Technology WL-U357 - Manual (Page 35)

military for use in reliable, secure, mission-critical communication systems. It is designed to
trade off bandwidth efficiency for reliability, integrity, and security. In other words, more
bandwidth is consumed than in the case of narrowband transmission, but the trade off
produces a signal that is, in effect, louder and thus easier to detect, provided that the receiver
knows the parameters of the spread-spectrum signal being broadcast. If a receiver is not tuned
to the right frequency, a spread –spectrum signal looks like background noise. There are two
main alternatives, Direct Sequence Spread Spectrum (DSSS) and Frequency Hopping Spread
Spectrum (FHSS).
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