Full duplex radio (FDR) can double the capacity of a
communication system, and it attracts much
research attention recently. In 2013, a research team in
Stanford University announces that it has
successfully developed a FDR system. As well known, the key
problem in a FDR system is the
self-interference (SI) cancellation. The Stanford team claim
that more than 110dB cancellation can
be achieved. With the cancellation amount, the residual SI
can be reduced under the noise level.
This purpose of this talk is to give an introduction of FDR
systems, both in PHY and MAC layers.
First, the architecture of Stanford solution is reviewed.
Three stages of cancellation are involved,
i.e, circulator, analog, and digital cancelation. Related
algorithms for the identification of the
cancelers will be addressed. Then, MAC protocols and issues
for FDR networks will be discussed. It
is found that the network capacity can be double if the
protocol is properly designed.
Finally, a FDR prototype built by our team, having the
capability of 100dB SI cancellation,
will be briefly described.