In an effort to resolve the ongoing available spectrum issue, researchers at the University of California at Riverside have developed a way to double the efficiency of wireless networks.
The researchers theorized that the use of modified full-duplex radios, which transmit signals at the same time in the same frequency band, could double the efficiency of the spectrum. Current radios for wireless communications are half-duplex and transmit and receive signals on separate channels. However, the technology to eliminate the interference between transmitted and received signals in a full-duplex radio does not currently exist for 3G and 4G networks.
To combat the issue, the UC Riverside researchers developed a solution known as “time-domain transmit beamforming,” a technique that “digitally creates a time-domain cancellation signal and couples it to the radio frequency frontend.” Using this solution, the radio is able to simultaneously detect weaker incoming signals while transmitting more powerful outgoing signals at the same frequency.
According to Ping Liang, professor of electrical engineering at the UC Riverside Bourns College of Engineering, “the future applications of full duplex radios are huge, ranging from cell towers, backhaul networks and wireless regional area networks to billions [of] handheld devices.”
Liang adds that he and his colleagues have already discussed their interference solution with several major wireless telecommunication equipment companies.
