On June 30th 1948, The New York Times devoted a 4-inch article on page 46 to a new invention: “A device called a transistor, which has several applications in radio where a vacuum tube ordinarily is employed”.  The article unveiled what Bell Labs (the R&D Department of the American telephone operator AT&T) had been developing and patenting since 1947. This modest announcement of what was to become the central artefact of electronics, was followed by a relatively non-aggressive plan of action for introducing the product on the market. AT&T waived the royalties for transistorized hearing aids in honor of Alexander Graham Bell, a lifelong advocate for the hearing impaired. There were not many more applications for the transistor technology in sight.
In my previous article on “Positioning systems and mobility management I” looked at the Wi-Fi infrastructure solution within a given area.
The location of a client carrying a Wi-Fi-enabled device could be estimated based on the information received from several APs about a client’s proximity. The client didn’t even have to connect to the network, just having the interface turned on was enough.