Born on November 9, 1914, in Vienna, under the initial name, Maria Kiesler, being one of the women who marked history, Hedy Lamarr is well known, in addition to her successful film career, as inventor of a device that preceded wireless communication systems, used today on smartphones, tablets or other electronic devices.
Hedy Lamarr (November 9, 1914 - January 19, 2000)
The prototype worked with radio waves and used frequency hopping to block the interception of transmitted information.
What are frequency hops?
Frequency jumps are used in transmission systems whose frequency bands are divided into a finite number of channels (sub-bands), each channel having sufficient bandwidth to comprise most of the modulated signal strength (FSK). or QAM).
Exist two transmission techniques Frequency Hopping / Spread Spectrum (FH / SS):
- fast (two or more frequency jumps are made on each transmitted symbol);
- slow (two or more symbols are transmitted on the same frequency) and with direct sequence (DS / SS - Direct Sequence / Spread Spectrum).
Example of frequency hopping measurement
The first Wi-Fi precursor ideas
In addition to its success in cinema, it became famous for patenting the so-called technological method "Secret Communication System" (secret communication system), which became important for the security of military communications and for mobile telephony technology in 1942.
Inspired by the way the piano works, together with George Antheil, Hedy Lamarr supported the idea of controlling torpedoes by radio. In the past, radio control seemed like an ingenious idea, but impossible to achieve. That's how he was born the concept of frequency hopping, the original form of today's spread spectrum communications technology.
Charles Kettering, Prime Minister, helped improve the project by releasing the patent in her present and marriage name, Hedy Kiesler Markey, August 11, 1942.
Although the invention was donated to the US Navy, it did not use it in the battles of World War II, being reconsidered in the 1950s. The invention was the basis for the development of wireless communication systems that we use today.
Now the concept is applied by the military and has become the technology behind the latest Internet transmissions and the most modern cell phones.