Did you know?

by techtiptom

Originally posted to wibc.com on 01/23/2012

Did you know?

Hedy Lamarr was an Austrian-American actress celebrated for her great beauty who was a major contract star of MGM’s “Golden Age” (1931-1941)…..

What most folks don’t know is, Lamarr also co-invented an early technique for spread spectrum communications and frequency hopping, necessary to wireless communication from the pre-computer age to the present day.

Spread-spectrum techniques are methods by which a signal  generated in a particular bandwidth is deliberately spread in the frequency domain, resulting in a signal with a wider bandwidth. These techniques are used for a variety of reasons, including the establishment of secure communications, increasing resistance to natural interference, noise and jamming, to prevent detection, and to limit power flux density (e.g. in satellite downlinks).

Frequency-hopping spread spectrum (FHSS) is a method of transmitting radio signals by rapidly switching a carrier among many frequency channels, using a pseudorandom sequence (a process that appears to be random but is not.)  known to both transmitter and receiver. It is utilized as a multiple access method in the frequency-hopping code division multiple access (FH-CDMA) scheme.

Please send me your “Did You Know?” items, to “techtiptom@wibc.com!

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