The University of Bristol says a team from its Communication Systems and Networks research group has developed a technique that can estimate and cancel out the interference from one's own transmission. This would allow a radio to transmit and receive on the same channel at the same time and therefore use only half the spectrum needed by current technology.
The full duplex transceiver architecture, which combines electrical balance isolation and active radio frequency cancellation, is said to suppress interference by a factor of more than 108 using low cost, small form factor technologies. The development is said to be well suited to use in mobile devices.
PhD student Leo Laughlin said: "Until now, there has been a fundamental unsolved problem with radio communication. Since the radio spectrum is a limited resource, and with network operators paying billions of pounds to access the spectrum, solving this problem would bring us one step closer to the faster, cheaper and greener devices of our connected future."
Using this approach would allow the capacity of a Wi-Fi access point to be doubled or a network operator to provide the same capacity using fewer basestations.
As well as being part of the evolution to 5G mobile, this research is also very relevant to the design of the radio circuitry in current 3G and 4G cellular mobile devices. In today's mobile devices, a separate filtering component is required for each frequency band, and because of this, today's mobiles phone do not support all of the frequency channels which are in use across the world. Different devices are manufactured for different regions of the world, and
The team also notes there are currently no 4G phones capable of unrestricted global roaming. Replacing the frequency filters in these phones with the team's duplexer circuit could create smaller and cheaper devices and allow manufacturers to produce one device that would support global 4G roaming.
Pic: Image: Sam Duckerin
Author
Graham Pitcher
Source: www.newelectronics.co.uk