Researchers from Rice University’s Wireless Network Group have developed a wireless means of sending lots of data fast and far using a multi-user, multi-antenna transmission system over UHF frequency bands typically used for television broadcasts.
Leveraging several different technologies that are widely used for wireless data transmission, the Rice research team employed multiple antennas to boost data rates without having to add channels or boost transmitter power.
Their approach to MIMO (multiple-in, multiple-out) antenna technology effectively creates a fatter wireless pipe through which to transmit data using technology that is standard in the latest generation of wireless routers and networking equipment, Rice University’s David Ruth and Jade Boyd explain in a Rice University news release.
UHF Wireless Data
“The holy grail of wireless communications is to go both fast and far,” lead researcher Edward Knightly, professor and chair of Rice’s Department of Electrical and Computer Engineering, was quoted as saying. “Usually, you can have one or the other but not both. Wireless local area networks today can serve data very fast, but one brick wall and they’re done. UHF can travel far, but it hasn’t had the high capacity of WiFi. This provides the best of both worlds.”
Able to transmit signals over long distances, UHF bands were opened to other forms of radio frequency signals in the wake of the switch to digital television broadcasting. Some propose using the new UHF spectrum to support “open” WiFi hotspots, which could make it easier to deliver wireless broadband services to rural and other underserved areas.
“When comparing UHF and WiFi, there’s usually a trade-off of capacity for range or vice versa,” Rice graduate student Narendra Anand, the lead author of the new study, explained. “Imagine that the WiFi access point in your home or office sends data down a 100-lane highway, but it’s only one mile long. For UHF, the highway is 100 miles long but only three or four lanes wide. And you cannot add any lanes.
“To be able to leverage the best characteristics of the UHF band, we need to be able to efficiently use the lanes that we have,” Anand continued. “One way to do that is with multi-user MIMO, a multi-antenna transmission technique that serves multiple users over the same channel simultaneously.”