Spread Spectrum Communications: Origins
Of Spread-Spectrum Communications
2. Origins of Spread Spectrum Communications
Initially, Spread Spectrum was known as Noise Modulation.
This was because the spread spectrum signals look more like
a noise to an ordinary AM/FM receivers due to spreading
of signals over a large bandwidth (typically several 1000
times the signal bandwidth). Spread Spectrum techniques
were used initially for military communications due to inherent
coding (encryption) of SS Communications System. The initial
use of spread spectrum was during World War , by using pulse-to-pulse
frequency hopping radar called reisslans. The mid 1940s
a matched filter concept was used for maximum signal-to-noise
ratio pulse detection.