Radio communications: Tripling channel capacity

One of the most promising areas of progress in the theory of wireless communications is the use of multiple and 'smart' antennas to increase the channel capacity for radio links; this can involve the use of various polarizations in the transmitted signals. This method has now been extended by the use of magnetic as well as electric field components, giving the potential to increase channel capacity by a factor of three compared with conventional dual-polarized radio signals.

Tripling the capacity of wireless communications using electromagnetic polarization
MICHAEL R. ANDREWS, PARTHA P. MITRA, ROBERT DECARVALHO
Nature 409, 316-318 (18 January 2001)
| First Paragraph | Full Text | PDF |

Talk is cheap in the city
HENRY L. BERTONI
Telecommunications companies have paid a heavy price for their share of the radio spectrum. So they have been quick to exploit 'multiple antennas' that can increase transmission rates in urban areas.
Nature 409, 291-292 (18 January 2001)
| Full Text | PDF |

physics: Information goes round the bend
The data capacity of cellphone networks can be expanded by harnessing bouncing signals. (18 January 2001)

18 January 2001 table of contents