spread spectrum



  • Any modulation technique in which the bandwidth of the information-bearing signal is intentionally spread over a much wider bandwidth than would otherwise be necessary. This may be done, for instance, for added security or for the ability to recover the data without retransmission. Examples include frequency hopping spread spectrum, in which the frequency of the carrier hops among multiple frequencies at a rate determined by a specific code or algorithm, and direct-sequence spread spectrum, where the information-carrying bit stream is combined with a pseudorandom bit stream at a higher bit rate, and this combined signal modulates the carrier. Also, the technology utilized to implement any such technique. Also called spread-spectrum modulation, or spread-spectrum technique.
  • A transmission utilizing a spread spectrum (1) technique or technology.