Statistical multiplexing technologies inherent in
multipoint microwave backhaul solutions take advantage of this lack of
correlation when they aggregate traffic from multiple cell sites. The ‘troughs’
of one cell site are filled by the ‘peaks’ of others, resulting in the total
bandwidth requirement being significantly reduced.
Without aggregation, the mean microwave backhaul network
efficiency is typically around 25percent. This result in 75percent of the cost
to not being utilised provision a link (link radio cost and spectrum). This
‘white space’ is effectively trapped in each link and not available for use.
Live traffic measurements with Cambridge Broadband
Network’s VectaStar multipoint microwave technology shows bandwidth efficiency
is increased to 55 percent.
“The data we’ve released today is hard evidence of
the benefits of statistical multiplexing in multipoint microwave. No operator
can afford to ignore the potential to reduce bandwidth requirements by 40
percent. That is particularly applicable as operators transition to LTE and
will apply equally in the backhaul of the small cell networks now being
investigated around the world,” said John Naylon, head of R&D at
Cambridge Broadband Networks.
Unlike traditional point to point microwave systems,
multipoint microwave solutions are able to release the additional headroom
created by the increased efficiency to any site in the sector on demand
delivering superior customer experience when the customer or site requires
additional resources.
Further investigation indicated that a point to point
microwave system would require 20.3MHz of spectrum to carry the peak traffic
load whereas the VectaStar system was using only 12.1MHz, realising a 40percent
reduction in spectrum bandwidth.
In practice the results would be much different with the
point to point links likely to be dimensioned at 20 Mbps or more in order to
deliver the peak potential of the mobile network. In this case the savings
would be greater still.
By Telecomlead.com Team
[email protected]