Guglielmo Marchese Marconi, Italian electrical engineer and Nobel laureate, known as the inventor of the first practical radio-signaling system. He was born in Bologna and educated at the University of Bologna. As early as 1890 he became interested in wireless telegraphy, and by 1895 he had developed apparatus with which he succeeded in sending signals to a point a few kilometers away by means of a directional antenna.
After patenting his system in Great Britain, he formed (1897) Marconi's Wireless Telegraph Company, Ltd., in London. In 1899 he established communication across the English Channel between England and France, and in 1901 he communicated signals across the Atlantic Ocean between Poldhu, in Cornwall, England, and St. John's, in Newfoundland, Canada. His system was soon adopted by the British and Italian navies, and by 1907 had been so much improved that transatlantic wireless telegraph service was established for public use.
Marconi was awarded honors by many countries and received, jointly with the German physicist Karl Ferdinand Braun, the 1909 Nobel Prize in physics for his work in wireless telegraphy. During World War I he was in charge of the Italian wireless service and developed short-wave transmission as a means of secret communication. In the remaining years of his life he experimented with shortwaves and microwaves.
After patenting his system in Great Britain, he formed (1897) Marconi's Wireless Telegraph Company, Ltd., in London. In 1899 he established communication across the English Channel between England and France, and in 1901 he communicated signals across the Atlantic Ocean between Poldhu, in Cornwall, England, and St. John's, in Newfoundland, Canada. His system was soon adopted by the British and Italian navies, and by 1907 had been so much improved that transatlantic wireless telegraph service was established for public use.
Marconi was awarded honors by many countries and received, jointly with the German physicist Karl Ferdinand Braun, the 1909 Nobel Prize in physics for his work in wireless telegraphy. During World War I he was in charge of the Italian wireless service and developed short-wave transmission as a means of secret communication. In the remaining years of his life he experimented with shortwaves and microwaves.
1895年夏天，马可尼又完成了一次非常成功的实验。到了秋天，实验又获得很大的进步。他把一只煤油桶展开，变成一块大铁板，作为发射的天线。把接收机的天线高挂在一棵大树上，用以增加接收的灵敏度。他还改进了洛奇的金属粉末检波器，在玻璃管中加入少量的银粉，与镍粉混合，再把玻璃管中的空气排除掉。这样一来，发射方增大了功率，接收方也增加了灵敏度。他把发射机放在一座山岗的一侧，接收机安放在山岗另一侧的家中。当给他当助手的同伴发送信号时，他守候着的接收机接收到了信号，带动电铃发出了清脆的响声。这响声对他来说比动人的交响乐更悦耳动听。这次实验的距离达到2.7公里。
1901年马可尼认为实现他的宏伟计划的时机已经成熟，他希望能在大西洋彼岸的美国接受到从英国所发出的电报。他在纽芬兰登岸后，先放起一只用丝竹做成的飞机形状的风筝，却被大风撕裂了。他又放起了一个气球，也被大风刮到海里去了。最后，他放起一只做工很结实的风筝，风筝终于飘上天空。他听了好几小时，急切地盼望能从英国拍来的讯号。就在他要开始灰心丧气的时候，他忽然听见了一点微软的嘀嗒声。然后一声接一声，那就是他们事先商量好了的那种信号——代表字母S的三点。马可尼不禁欣喜万分，很想跑到外面向全世界喊出这一激动人心的消息。然而，他并没有这样做，他怕人们不相信他，所以他一直将这个秘密保守了48小时之久，没有告诉任何人。后来，他鼓起勇气将这件事情的经过拍了10个电报传回伦敦，这一事件立即以其轰动，全世界的各大报纸都报道了这一伟大的新闻，科学界的人大为振奋。
