Digital Signal Processing Reference
In-Depth Information
Fig. 8.2
Future network architectures go distributed for sustainable growth
8.2 Closing Remarks: The End Is Not There nor in Sight
8.2.1 Keep Moving with the Target
We closed a previous topic with the statement “This is not the end, its just the be-
ginning” [1]. Following straight engineering logics, the ideas presented in this topic
building on SDRs and DSA are consequently not anymore the beginning of Software
Defined Radio solutions. Yet, this is definitely not the end, nor is the end in sight. In
this topic we advocate smart(er) and cognitive radios as an answer to the bottleneck
that will occur following the ever increasing wireless data traffic within limitations
of available spectrum. Recently, the energy consumption of (wireless) communica-
tion systems and the impact of the emitted electromagnetic radiation have become
a cause for concern. Worldwide, initiatives have been launched and are gaining mo-
mentum to radically reduce the overall energy consumption of communication net-
works and to reduce the carbon footprint of the growing network [130]. If we want
to build tomorrows wireless communications systems, we need to minimize the en-
ergy consumption and restrict the radiation, but not at the penalty of throughput and
intelligent operation. An answer to this challenge showing great potential savings is
the approach to restrict wireless communication to short ranges whenever possible.
Indeed today many connections, specifically mobile phone calls, connect to a rela-
tively faraway base-station, even if much closer access points (e.g. indoor WLAN)
are present. On the longer term, one may even enable 60 GHz-based local wire-
less access, allowing very directive transmission at data rates that exceed 1 Gbps.
This concept based on distributed access in a heterogeneous network environment
is illustrated in Fig.
8.2
.
A major part of the radiation and the wasted energy can be avoided and high
data throughput is enabled. In order to enable this, multi-standard terminals, which
can be realized attractively (both for cost and form factor) when based on recon-
figurable radio solutions, will be key. Energy efficient operation of these radios is
