User's Manual

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13. What is Spread Spectrum？
Spread Spectrum technology is a wideband radio frequency technique developed
by the 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).