五千年(敝帚自珍)

主题:干通讯的,进来一起驳一个伪科普yy -- phjhuan

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家园 刚才wiki了一下

发现这个事还挺复杂的。

wiki上关于Hedy Lamarr的话,就是上面中文的原版,不值得信。

关于Frequency-hopping spread spectrum那一段的:

Perhaps the earliest mention of frequency hopping in the open literature is in radio pioneer Johannes Zenneck's book Wireless Telegraphy (German, 1908, English translation McGraw Hill, 1915), although Zenneck himself states that Telefunken had already tried it.

The German military made limited use of frequency hopping for communication between fixed command points in World War I to prevent eavesdropping by British forces, who did not have the technology to follow the sequence. [1]

A Polish engineer, Leonard Danilewicz, came up with the idea in 1929.[2] Several other patents were taken out in the 1930s, including one by Willem Broertjes (U.S. Patent 1,869,659, issued Aug. 2, 1932).

During World War II, the US Army Signal Corps was inventing a communication system called SIGSALY, which incorporated spread spectrum in a single frequency context. However, SIGSALY was a top-secret communications system, so its existence did not become known until the 1980s.

The most celebrated invention of frequency hopping was that of actress Hedy Lamarr and composer George Antheil, who in 1942 received U.S. Patent 2,292,387 for their "Secret Communications System." This early version of frequency hopping used a piano-roll to change between 88 frequencies, and was intended to make radio-guided torpedoes harder for enemies to detect or to jam. The patent was rediscovered in the 1950s during patent searches when private companies independently developed Code Division Multiple Access, a civilian form of spread-spectrum.

这个很清楚的写明了这个美女不是第一个发明的。但里头又说她的发明是The most celebrated invention of frequency hopping 。

通过www.google.com/patents查了2292387号专利,发现还真有这个专利,还被不少专利引用。

专利名字不一样,但这个传奇故事又说她改了名的。

wiki里头Frequency-hopping spread spectrum就说到她发明的目的就是为了制导鱼雷 radio-guided torpedoes 难于被敌人detect or to jam。但无线遥控鱼雷就不可能,还干扰什么。

为了证实不存在这个傻无线制导鱼雷radio-guided torpedoes,又Google一下,发现这个词就和两个人相关,一个就是这个美女。

一个是交流电的发明人Tesla,1897年搞了个专利,请注意,那是1897年,马可尼才开始实验无线通讯,鱼雷也发明不久,这只是个幻想。

可以说,就没人傻到会在战争中用无线去制导鱼雷。

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