What Is Wireless Spread Spectrum Communication?

From WWII to Modern Wi-Fi

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The spread spectrum approach to wireless communications is employed today in Wi-Fi and some cellular networks to obtain the following benefits:

  • Enhanced reliability - mitigates the impact of wireless interference on a communication channel
  • Increased bandwidth - exploits additional wireless spectrum to better utilize and share bandwidth among multiple channels
  • Improved security - limits the ability of attackers to intercept transmissions

The main idea behind spread spectrum is to separate a wireless communication into a set of related transmissions, send the messages across a wide range of radio frequencies, then collect and recombine signals on the receiving side.

Several different techniques exist for implementing spread spectrum on wireless networks. Wi-Fi protocols utilize both frequency hopping (FHSS) and direct sequence (DSSS) spread spectrum.

History of Spread Spectrum Technology

Spread spectrum technology was originally developed to improve the reliability and security of radio transmissions, primarily for military communications systems. Prior to and during World War II, several famous individuals were involved in early research on frequency hopping spread spectrum applications including Nikola Tesla and Hedy Lamarr. Before Wi-Fi and cellular networks became popular, the telecommunications industry began rolling out various other applications of spread spectrum starting in the 1980s.