As we contemplate the arrival of 4th-Generation mobile wireless capabilities in the form of the LTE standard, I’m going to take us back in time to reflect on an unlikely and intriguing true story from the archives of radio communication history.
GSM is far more widely deployed than CDMA – the former is widely considered to be a de facto global standard. Whereas CDMA is mostly limited to the U.S. and Canada, along with a few deployments in Asia. Both mobile radio standards are used to establish and manage the wireless connection between a mobile device and the nearest cell tower.
GSM evolved in a rather typical, logical, and linear way, with new capabilities being appended onto the standard as they were created and demanded. CDMA, on the other hand, had a much more colorful development path.
Unusual Source for a Wireless Network Standard
During the 1930s, the most beautiful woman in the world was considered to be Austrian actress Hedy Lamarr. A Hollywood icon, Lamarr starred in a number of less-than-memorable movies, although one of them — Samson and Delilah — garnered her a certain amount of acclaim.
She was a controversial, feisty character who married six times in her life, the first time to arms dealer Fritz Mandel. The marriage was doomed to failure because Mandel was controlling and abusive, but one good thing came from the relationship. Because he was involved with weapon applications, Mandel had to deal with quite a few military hardware related problems — one of which was a vexing inability to prevent the enemy from jamming the radio control signals for guided torpedoes.
Somewhere along the way, Lamarr met orchestra conductor George Antheil. He was a fan of player pianos, and in fact created a performance that involved multiple carefully-synchronized pianos. Lamarr, aware of the torpedo guidance issue — and wanting to be known for something other than her beauty — worked with Antheil on his synchronized piano concept and soon discovered a solution to the otherwise unrelated problem.
The discovery: an ability to synchronize paper rolls in the player pianos gave her the idea that ultimately became the radio communication technology known as Frequency-Hopping Spread Spectrum.
An Invention, Two Decades Before its Time
Imagine two people who want to communicate privately. A third party (think of an orchestra conductor) simultaneously directs the two parties to jump from frequency to frequency at random intervals, making it effectively impossible to eavesdrop on the conversation – or to jam a torpedo control signal based on the technology.
Think of a checkerboard, where each square on the board represents a different operating frequency. The third party instructs the two would-be communicators to simultaneously jump from square to square very rapidly, making it difficult to follow them.
Lamarr and Antheil were granted a patent for their invention called “Secret Communications,” yet ironically they never made a penny on it. In fact, neither was recognized in any way until the 1990s — in spite of the fact that, by that time, the technology was in widespread use by the military.
In 1997 the Electronic Frontier Foundation (EFF) granted Lamarr and Antheil the Pioneer Award, a rather prestigious honor. Lamarr’s response was interesting: “About time.”