Radio receiver crude triode, was invented in 1906 by Lee De Forest as a more sensitive detector for radio receivers, by adding a third electrode to the thermionic diode detector, the Fleming valve. It was not widely used until its amplifying ability was recognized around 1912. The first tube receivers, invented by De Forest and built by hobbyists until the mid 1920s, used a single Audion which functioned as a grid-leak detector which both rectified and amplified the radio signal. There was uncertainty about the operating principle of the Audion until Edwin Armstrong explained both its amplifying and demodulating functions in a
Xiaodong Wang (electrical engineer) Conference. Wang has many research interests, but chooses to focus on the areas of information theory, signal processing, and communications. Furthermore, he has influential published research in the areas of wireless communications, statistical signal processing, parallel and distributed computing, nanoelectronics, and quantum computing. In 2003 he published a book entitled "Wireless Communication Systems: Advanced Techniques for Signal Reception", published by Prentice Hall. Recently he is also working on the emerging field of genomics signal processing and information theoretic genomics. Xiaodong Wang (electrical engineer) Xiaodong Wang () is an information theorist and professor of Electrical Engineering at Columbia University. He earned