I came across this a few years ago and thought it quite interesting.

Hedy Lamarr along with George Antheil were granted the patent for frequency hopping (CDMA) in 1942 and is used in satellite and cell phone communication.

http://www.biography.com/people/hedy-lamarr-9542252
http://en.wikipedia.org/wiki/Hedy_Lamarr#Frequency-hopping_spread-spectrum_invention
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http://www.cdg.org/technology/cdma_technology/a_ross/bibliog.asp

R. Price, "Further notes and anecdotes on spread-spectrum origins," IEEE Trans. Commun., COM-31, pp. 85-97, Jan. 1983.

These three papers are a fascinating account of the historical origins of spread spectrum. Early events include the bizarre story of U. S. Patent number 2, 292, 387, granted in 1942 to Hedy K. Markey and George Antheil, neither of them ENGINEERS, for "SECRET Communication System." Hedy K. Markey was better known at the time under her Hollywood stage name, Hedy Lamarr. Antheil was a composer of symphonies, which may account for the statement in the disclosure that a frequency hopping repertoire of 88 frequencies could readily be accommodated. Hints of spread spectrum techniques actually can be found in work as early as 1901. Very interesting materiel.
Hedy Lamarr

For years many have worked against frequency hopping due to the need of a fast controller to make it work. Conventional Radio and Television still sticks to the concept of one frequency, one owner.
But modern microwave communication depends on spread spectrum to reduce interference and multiple paths lose.
For those who want more technical information, here is a place to start.
http://people.seas.harvard.edu/~jones/es151/prop_models/propagation.html
Quote

Introduction
Land-MOBILE communication is burdened with particular propagation complications compared to the channel characteristics in radio systems with fixed and carefully positioned antennas. The antenna height at a mobile terminal is USUALLY very small, typically less than a few meters. Hence, the antenna is expected to have very little 'clearance', so obstacles and reflecting surfaces in the vicinity of the antenna have a substantial influence on the characteristics of the propagation path. Moreover, the propagation characteristics change from place to place and, if the mobile unit moves, from time to time. Thus, the transmission path between the transmitter and the receiver can vary from simple direct line of sight to one that is severly obstructed by buildings, foliage and the terrain.