Fujitsu Plans to Double the Capacity of Each Cell through Task-Sharing and Efficient Scheduling

By CIOReview | Wednesday, September 23, 2015

FREMONT, CA: Fujitsu has come up with the idea of developing the technology that doubles the capacity of individual cells in a cellular network through task-sharing and efficient scheduling; and hopes to implement commercially it by 2023.

This new advent in the cellular network standards uses same frequency for transmitting and receiving simultaneously called Full Duplex technique; realized by the 4G/LTE spectrum. The technique saves half the spectrum with same speed and capacity; saves carriers, billions of dollars on license auctions.

Providing simultaneous transmission and reception is considered difficult to achieve, because massive interference occurs on transmitting signals which may leak into adjacent receivers. This self-interference forces to adapt half-duplex transmissions, using either different frequencies or different time for transmission and reception.

The company aims at overcoming the challenge by placing transmitters and receivers in different locations, assigning receiving and transmitting to different base stations. That is, large base stations to transmit data and small ones to receive signals from devices.

The proposed technique will be realized by automatically choosing two devices in a small cell having less mutual interference when used in same frequency. The interference can be reduced by controlling the transmission power. Fujitsu’s scheduling algorithm improves signal-processing workload by prioritizing the network devices based on transmission power. Whereas, another algorithm accurately picks transmission-power candidates based on the grouping of devices, which reduces the processing workload to about one-fortieth overall.

The end result is that the small cells double their communication capacity, especially useful in crowded areas such as shopping malls and stadiums, where cellular capacity can be squeezed.

There are several other possible contenders for the full-duplex technology. Columbia University in New York has announced that it has created full-duplex radio integrated circuits; Stanford University is been working on self-interference cancelling algorithms and researchers at the University of California, Riverside, has come up with an in-radio signal-canceling circuit.