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Did Hedy Lamarr really invent frequency-hopping, or spread spectrum switching?

Ok..I guess the first question that comes to mind is: What is frequency hopping, or spread spectrum switching.  I’ll get to the Hedy Lamarr aspect presently.

Our story starts way back in the early 1940’s, after the outbreak of World War II.  The British navy (and the U.S. navy, after America joined the war effort), were using a radio control system to guide torpedoes from their ships to destroy the German battleships and submarines.  The technology of the day used a fixed radio broadcast frequency to communicate to a receiver in the torpedoes.  The problem was that the transmitted signal, being a steady tone, was easily picked up by the German radio equipment, allowing them to ‘jam’ or interfere with the signal, and steer the torpedo off course.

What was needed was a different broadcast method, making it fairly impossible to lock onto the signal.  This is where the story takes a rather odd turn…

The glamorous Hedy Lamarr

The glamorous Hedy Lamarr

We now take you to Hollywood, California…

Hedy Lamarr was one of many glamorous Hollywood actresses of the 1940’s, along with Katherine Hepburn, Ingrid Bergman, etc.  While she may be less well-known today, she was well-regarded in her day for her acting abilities and striking good looks.  She was no dumb, glamorous air-head though.  She was one smart cookie, as they say.

In 1933 in her native Austria, she married an industrialist, Fritz Mandal, who specialized in munitions and weapons control systems.  He was very protective (perhaps jealous) of his beautiful wife, so she accompanied him wherever he went.  She was privy to some detailed discussions with colleagues about weapons control systems.  She wasn’t just sitting around looking pretty either, she was taking it all in.  She started getting some ideas on how to solve the problem of tracking and guiding torpedoes.

Eventually, she divorced her husband, then moved to England and America to pursue her acting career.  In the early 1940’s, while making a name for herself on the silver screen, she met with a composer and writer by the name of George Anthiel.  They ended up discussing all kinds of things, including the ongoing World War II.

Hedy Lamarr's ingenious invention...

Hedy Lamarr came up with an idea for tracking torpedoes that used a method that rapidly switched the transmitted frequencies (referred to as ‘frequency hopping’) such that the enemy wouldn’t be able to pick up and interfere with the transmission. George Anthiel’s idea was to use a punched-paper mechanism, similar to the paper roll of a player-piano, to switch frequencies. The trick was co-ordinating the signals between the control ship, and the torpedo. Once that problem was more or less solved, they applied for a patent on the process, which they were awarded in 1942.

Unfortunately, the U.S. navy, though they realized the idea had merit, felt the idea was too impractical, and considering that the [inventors] were first and foremost..entertainers, and that neither of them had any scientific or practical training, they dismissed the idea, and didn’t pursue it further.

However, in the late 50’s, with the advent of the transistor, the concept was resurrected, further developed and put to use by the navy. Although their patent had expired by this time, the Lamarr-Anthiel patent was cited as the basis for the navy’s torpedo control systems. Ultimately it was employed as part of the naval blockade off Cuba in 1962.

The story doesn’t end there, however…

Modern day use of frequency hopping – spread spectrum

Military organizations throughout the world have been using a similar system for a few decades. It has several advantages over a single transmission frequency.

  • Superior immunity from adjacent channels and external interference
  • Intercepting transmissions by outside receivers is much more difficult
  • More efficient use of the available bandwidth
  • Many users can share the same transmission bandwidth without stepping on each other’s toes

Flash forward to the 1980’s, with the introduction of mobile phones. Unlike standard, land line telephones, which have a dedicated line for each user, mobile phones, and cellphones share a wide-bandwidth carrier channel. This channel (depending on the size) can handle anywhere from a few dozen to many thousands of discrete transmissions.

Each wireless phone transmission contains a pseudo-random code, and the equipment at the receiving end knows how to decipher the code and figure out which bits are for your wireless phone only..then pass on the data message it contains. The amazing thing is that your message is being rapidly switched along this channel, thousands of times per second. This is what makes it relatively immune to interference while walking around, or driving past many tall buildings and other structures.

Going wireless...

Wireless networks for the home or business, cordless phones, and radio-controlled planes and models use this same technology. Wireless networks use special protocols to send and receive data messages. In all of these systems, it is possible to also use data encryption. This adds an extra layer of security, just in case the transmission code and the method is deciphered, it would take a great deal more effort to crack the encryption, and unravel the original message.

However, rather than get into a detailed technical explanation of how spread spectrum or frequency hopping works, all you really need to know is that the technology that makes it possible, works quietly and efficiently in the background. Plus, the technology is getting better and more efficient and cost-effective all the time.

Now all we need is smaller fingers, and magnifying glasses to use these ever-shrinking devices.

Recognition for lasting contributions…at last

By the way, even though Hedy Lamarr and George Anthiel never really received the recognition they deserved at the time, in 1997 Hedy Lamarr (and George Anthiel, in absentia – he died in 1959) were given the Electronic Frontier Foundation (EFF) Pioneer Award. Hedy Lamarr was also the first female to be given the BULBIE Gnass Spirit of Achievement Bronze Award given to inventors who have made a lasting contribution to society through science, business and the arts.

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So, the next time you pick up that cell phone and make or receive a call, you can quietly thank Hedy Lamarr and George Anthiel for planting the seed that made it all possible.

This article ©2011 by timorous

Your comments are always welcome...

Tim Nichol (author) from Me to You on May 21, 2018:

Hi Paul;

I have yet to see the doc, so far. The info in this article was as much semi-reliable info as I could find, when I first wrote it.

At this late date, it's difficult to know who's got the real facts, since virtually anyone who knew for sure, has passed away. Kind of like the JFK assassination...

Ms Lamarr does appear to have developed the idea, whether it was a technique known at the time or not. Being an actress primarily, she unfortunately wasn't given the credibility she might otherwise.

Technology has a way of marching forward, so it was only a matter of time that frequency hopping and packet switching would make their way into communications of all kinds.

Thanks for your comments.

Paul on May 21, 2018:

Interesting. This old blog is still timely.

Anyone see the PBS documentary about Hedy?

The documentary gave a lot of credit to Antheil

for implementing Hedy's idea (although they kind of

"dissed" him at the end).

They also insisted that Hedy was the

one-and-only devisor, and "pure" inventor of FHSS. They also

insisted that she did not spy on her husband. Both these presentations described in the documentary (per this blog, and other information) seem to be false. She did "spy" on her husband's work,

(fine with me if she ended up using it to stop the Germans in WWII)

and FHSS was already well known when she and Antheil patented

their invention.

You are correct Tim - Hedy deserves credit. But the deluge of

statements that we'd all be living without our smart phones without

her don't bear merit. And what about poor Mr. Antheil?

Google Hedy and Frequency hopping - you'll get - maybe - I don't know - 7 million hits? Do the same for George - I think I counted two hits. Makes one think that she never went to him for help...

Sorry if my post is too long Tim - blame it on Susan Sarandon - she produced the somewhat flawed documentary : )

Kenneth Grant on February 03, 2018:

Feminist revisionism...another brilliant inventor thwarted by the patriarchy

Kathleen Cochran from Atlanta, Georgia on August 16, 2017:

The history of women inventors is fascinating. Glad to read this hub on the topic.

Tim Nichol (author) from Me to You on November 11, 2015:

Thanks for your lengthy treatise, Stuart, even though you reapeated a lot of what I already wrote. I think your comment might be longer than my article..LOL.

It's hard to say whether, and how soon this 'idea' would have surfaced, had not Antheil and LaMarr presented it initially. It likely would have, as things seem to progress along these lines anyway. I don't think you're giving Ms. LaMarr enough credit though, and you are focusing on some of the gaps in her knowledge of the subject.

It does make for an interesting story though, and that was my main focus..not on the minute details you so astutely present here.

Stuart Fox on November 10, 2015:

Interesting story re Hedy Lamarr including as an inventor .... .... did Hedy Lamarr and George Antheil really invent Spread Spectrum / Frequency Hopping ? + WAS THEIR INVENTION USED and does she have “IMPACT TODAY” ? I have had a close look at the story in a logical and analytical approach.

Some interesting and varying stories – including in a biography - have been surfacing relatively recently re composer George Antheil and the Austrian born popular actress Hedy Lamarr – in particular that amongst their other talents they had invented Frequency Hopping / Spread Spectrum / wi-fi, GPS, Bluetooth, COFDM, CDMA and some even say they are responsible for the very creation of the mobile ‘phone. The concept that these two personalities actually INVENTED is certainly appealing and we may do well to consider further the facts of the story and hopefully the REALITY.

If a person has an idea for an objective to do something it is not considered an invention unless THEY propose a workable means to ENABLE that idea. For example having an idea to make chairs more compact when not being used - an objective, is an idea and may only be considered an invention when a means of actually achieving the objective – for instance a detailed folding mechanism – is devised + that THEY are recognised as INVENTORS and the first to do so. It is not enough to say “wouldn’t it be a good idea if chairs could be made more compact when not being used – that is a desire or objective rather than a means of achieving it (folding or stacking chairs). Further, other means of achieving the objective may be devised and in fact numerous different means of compacting chairs when not being used (the objective) have been patented including folding, stacking and inflatable chairs.

By the same token Mervin Richardson who started manufacturing Victa Rotary Blade Lawn Mowers was not the first to make that type of mower although he was a great marketer, ditto The Rotary Clothes Line was not invented by Lance Hill – but both are great stories we enjoy hearing – and ditto Kambrook and the so called ‘Power Board’ – all great stories .... but myths ... there are earlier American and other inventors. Similar ‘discussions’ and myths abound re many inventions.

The concept to in essence scramble / change frequency of a radio control system – in this case particularly for remotely controlled torpedos – by changing the transmitting and receiving frequencies – rapidly and co-ordinately – is an idea – ‘translating’ or converting that idea, by the claimed inventors, into a patentable invention (+ being the first to do so), is another challenge ... as Thomas Edison said in 1903 re invention (and genius) “1 percent inspiration and 99 percent perspiration” to develop and commercialise it.

Clearly everybody deserve respect and admiration for all their achievements and since the previously obscure claimed ‘secret patent’ (concerning Frequency Hopping / Spread Spectrum / wi-fi), co-registered in the name of George Antheil and Hedy Kiesler Markey, one of Hedy Lamarr’s married names, was publically linked to her better known persona as an actress, technocrats have been pondering. A first clue maybe (as included in many of the recent stories), was a Canadian companies (patent developer / trader –‘ Wi-Lan Inc.’) 1998 acquisition for an undisclosed sum, of a 49% claim to a patent describing well obsolete (by then) 1941/2 technology, from Antheil and Lamarr – one may well ask ‘acquisition of what’ – was it a publicity stunt concerning a long EXPIRED patent (Patent monopolies / rights only last 20 years now and 17 years from grant previously ... until 1995 ... AND it was never ‘worked’ by its maximum time limit ...1959, or even later) and therefore valueless patent? and which in any case had been allegedly previously assigned / donated to the US government to help the navy – no record that they – Lamarr and Anthil – clawed it back. Clearly there is a need to clarify the record. Another clue is an interview published by the US Military Journal ‘Stars and Stripes (see further details below) where Lamarr strangely refers to others “chemical implementation” of the invention as well as “thingamabobs” etc., the interviewer adding “Hedy was not too clear how the invention worked.” (so how could she be the inventor + see also the 5th last paragraph below. A person generally refers to ‘thingamabobs’ when they don’t really understand a mechanism etc. and there is nothing chemical re the invention – it was purely, electrical, mechanical and pneumatic [vacuum and pressure]).

George Antheil was a unique composer and Hedy Lamarr was a beautiful and talented actress as well as highly successful US charity fundraiser – (she raised around .3 billion in the 1940’s) - who was variously considered bright but were Lamarr and Antheil true inventors in the required terms ? Did their patent attorneys as well as an engineering professor inscribe the actual invention from an IDEA – AND where did the idea really originate + was it really patentable.

Numerous others had developed similar (patent /documented) technology years earlier.

Hedy Lamarr had a general interest in how things worked and her first of six husbands, Austrian Freidrich Mandl ran an armament business including supplying weapons to the Nazis. He was allegedly well versed in military science plus recognised the shortcomings of launch aimed though unguided electric motor powered German torpedoes travelling at much lower speeds than gun fired ammunition, necessitating spread multi barrages of expensive weapons (fired from considerable distances and also subject to water currents) rather than one accurate missile, to increase the likelihood that at least one hit the moving ship target - a possible plausible commercial attraction and motive to withhold a solution concept ? Mandl was also allegedly aware of the ‘hacking’ vulnerability of radio control including the then evolving German Fritz and Henschel ‘glide bombs’ utilising 18 pre-selectable frequencies (tuning).

After fleeing from an unhappy first marriage with her controlling husband (Mandl) and following her arrival in California, Hedy met composer George Antheil and they became collaborators in various ideas.

According to Antheil, munitions shortcomings and other matters were discussed by scientists with Hedy’s first husband in her presence and “she (allegedly) retained many overheard ideas in basic form, believing she knew enough to voluntarily initiate design of improved weapons giving her adopted country and other friendly nations a military edge” although this aspect led to contemplation whether the ideas were HERS originally or ‘borrowed’.

Arguably either Lamarr, Mandl or others MAY have conceived AN IDEA for non-hackable radio controlled torpedoes, by manually changing or ‘hopping’ the guidance carrier frequency ‘mid-shot’ to thwart interference – in effect a form of signal ‘scrambling.’ Fiercely pro-American following her emigration, she allegedly mentioned knowledge of torpedoes and the frequency changing idea to enamouree Antheil while they were “lying on a living room carpet” in Los Angeles. Whilst the transmitter could conceivably be manually controlled – like changing stations on a radio or television – how they might manually change the frequency on the torpedo as per their first concept, is unknown – actually inconceivable or suicidal ? and if the torpedo turned back ? Lamarr and Antheil submitted this as their first concept to the US governments National Inventors Council as a contribution to the war effort / preparedness and as might be expected, it was not well received. The US government ‘converted’ her representation into a request to promote US War Bonds which she happily did .... very successfully.

Tim Nichol (author) from Me to You on June 26, 2011:

Hi Bk. It's sad how narrow-minded some people can be, although it probably wouldn't have been practical until the invention of the transistor, anyway.

At least she got the recognition she deserved before she died. Thanks for enjoying the story and the for the 'up' votes.

BkCreative from Brooklyn, New York City on June 26, 2011:

It is so interesting that one's background is more important than one's intelligence. Sure the couple did this but they were entertainers and therefore they cannot possibly know what they were doing - in a different field. Well, sometimes it takes fresh eyes.

What a great hub - thanks a million! Rated way up!

Tim Nichol (author) from Me to You on June 16, 2011:

Hi kitty; Thanks for the votes, and I'm glad you enjoyed the my Hedy LaMarr article.

Kitty Fields from Summerland on June 16, 2011:

Voted up and beautiful! I love Hedy Lamarr and I had actually heard of her invention and genius mind before! Wonderfully written hub. Beautiful women can be smart, too!

Tim Nichol (author) from Me to You on April 15, 2011:

Hi G.L. Yes, it was only discovered about 15 years ago..perhaps by accident. She had used her maiden name on the patent, and most people had forgotten about George Anthiel. I couldn't find out who did the digging to reveal this interesting historical tidbit. Thanks for reading the article.

Hillary from Atlanta, GA on April 15, 2011:

Ok I have to admit I have seen a lot of Hedy's films including Ecstacy (not necessarily by choice), but I did not know her other, far more significant claim to fame. Very cool indeed!!

Tim Nichol (author) from Me to You on April 15, 2011:

I must admit, I'm not that familiar with her movie roles. She seems to have taken a back seat to Ingrid Bergman and the like. By the way, the early movie with the nude scenes is called 'Ecstacy'. You may be able to find an uncut version somewhere. Thanks for the votes.

Brian Lokker from Bethesda, Maryland on April 15, 2011:

Excellent hub! I'm familiar with Hedy Lamarr's acting career (including that first nude scene mentioned in the video), but I had never heard of her contribution to frequency-hopping technology. Fascinating. (Voted up and awesome.)

Tim Nichol (author) from Me to You on April 13, 2011:

Hello Simone.'s been a long time since I last saw Blazing Saddles. I'd forgotten that bit..haha. I'm so glad you found it fascinating. Thanks a bunch.

Simone Haruko Smith from San Francisco on April 13, 2011:

Oh, this is SO COOL! I had never heard of Heady Lamarr before. When I first saw the title, I thought you were referring to HeadLY Lamarr of Blazing Saddles- and I didn't get the Heady-Headly joke that ran throughout that movie until just now. This is a positively fascinating history. Thanks so much for sharing it!

Tim Nichol (author) from Me to You on April 13, 2011:

Thank you sofs. It was fun to research this story, partly because of the odd circumstances that led to the invention. So glad you found it as interesting as it was informative.

T.Q.M - Thanks for having a good read. Thanks also for the UP vote.

The Quiz Master on April 13, 2011:

Very interesting, just the kind of stuff I love to read.

Great hub, got a vote up from me.

Sophie on April 12, 2011:

Wow! this is one interesting and informative Hub. I need to acknowledge that, this is the first time I have come across this information. Well written and a wonderful read Tim. Awesome work here!

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