We have done some nice things here, together, in the last two years. The group includes electrical engineering faculty colleagues Zygmunt Haas, Venugopal Veeravalli and Sheila Hemami. Partly because their work has so many practical applications, it has brought in unprecedented support. Cellular phone companies, for example, pay enormous fees for the use of a small number of radio frequencies. They do that by dividing the world into small areas, or cells, so people in several cells can be talking on the same channel at the same time.
Computers can switch users from one frequency to another as they move between cells.
To keep users from interfering with one another, you also have to keep the power of the signal quite low. Cellular phone users want to carry on their conversations in elevators, walking down the street or even riding in trains going several hundred miles an hour. Much research goes into developing technology that can sort out these signals and correct errors, using special codes built into the transmissions that tell the receiver what the signal ought to look like. This allows for the transmission of data with extraordinarily weak signals. Turbo codes developed by one of Wicker's friends at NASA's Jet Propulsion Laboratory are already being used to verify data from the Cassini spacecraft, which has flown by the planet Venus and will eventually orbit Saturn.