Cellular-to-TV offloading could ease network congestion

Cellular signals could be opportunistically offloaded to TV and radio channels in the event that a natural disaster causes network congestion because too many people are trying to use their handsets at once, according to a Canadian doctoral student.

Mai Hassan, a student at the University of British Columbia, employed the concept of constructive/destructive interference to deliver cellular signals over TV or radio frequencies without interfering with signals already on those channels.

The approach developed by Hassan, whose study was published in the IEEE Transactions on Wireless Communications journal, entails changing a cellular signal's shape to suit radio or TV frequencies and then altering the direction of transmission away from the original channel. Using smart antennas in mobile phones, which can transmit signals in a single direction and steer the beam to any direction, Hassan was able to transmit calls and texts to a receiver while avoiding any interference with the original radio and TV signals.

"I proposed a more effective way to use any channel in the neighborhood, even if those channels are being used by radio or television stations," said Hassan. "The challenge was finding a way to make sure the cellular signals didn't interfere with the people using those channels in the first place."

For more:
- see this University of British Columbia article
- see this UPI article

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