Smart Antenna
Tired of broken cell-phone connections? Help is in sight. Michael Zoltowski, a professor of electrical and computer engineering at Purdue University, combines a pair of antennas with an advanced signal-processing algorithm to create a smart wireless receiver that rejects interference. The two antennas let phones or handheld devices “listen” for the cellular transmitter that is delivering the strongest signal. The receiver then ignores weaker signals while a “space-time equalization” algorithm restores the timing and sequence of codes that cellular base stations use to send data.
The result, Zoltowski says, could be as much as a hundredfold increase in reception accuracy. The technology should also triple the number of users that can occupy a given frequency band-a welcome development as wireless devices proliferate. Texas Instruments, which partially funded the research, is testing a two-antenna phone and hopes to incorporate Zoltowski’s algorithm into cellular systems within five years.
