Spectrum-Stretching Tunable Antennas to the Rescue

New types of antennas that are smart enough to dodge interference and stretch the usable radio spectrum are slipping into our cellphones—and just in time. Mobile customers’ demand for e-mail, streaming video, and apps is pushing telecom’s existing bandwidth capacity to the brink. The big U.S. wireless companies are falling over each other trying to buy up more radio spectrum, but they also need to use the spectrum already at their disposal more efficiently....