LINK LEVEL POTENTIAL
In the last decade, quite a number of improvements of radio interfaces [7] have been achieved,
boosting user data rates to the order of 100 Mb/s. State-of-the-art radio link designs focus on
achieving high peak data rates, optimal spectral efficiency, appropriate coverage, and low latencies.
In addition, it now becomes necessary to rethink the way radio interfaces are designed
from an energy efficiency perspective. Transceivers employing multiple transmit and
receive antennas boost spectral efficiency, in terms of b/s/Hz, which potentially allows to
transmit more bits for a given transmit power. In
practice, however, these improvements hardly
reduce the power consumption of the network.
The reasons for this are manifold, three examples
being discussed below.