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Motivated by the increasing demand for
higher data rate, broader coverage, and lower
infrastructure cost in wireless systems, a major
effort is being made to study the use of relay
stations in wireless networks. Base stations
require considerable infrastructure cost
whereas relays require very low-cost, operate
at low power, and have no connection to
wired infrastructure. Thus, the use of multi-hop
relaying can provide considerable performance
improvement to a wireless network through
coverage enhancement, range extension and
capacity enhancement, at relatively low cost
to the service provider. Studies have shown
that that use of relaying technology is a reliable
way to improve the performance through
Effect of Interference in Relay-Assisted Cellular Networks
Valentine A. Aalo, PI
l
Student: Constatntine Mukasa
cooperative diversity and extend the coverage
of many wireless communication systems. The
performance of a multi-hop relaying system
with amplify-and-forward (AF) transmission
in which the transmitted signal propagates
through cascaded nodes, with each node
amplifying and forwarding the received signal
from the previous node to the next node, is
sometimes of interest. Figure 1 shows a relay-
assisted cellular network. However, in practice
impairments such as co-channel interference
(see figure 2) is inevitable due to aggressive
frequency reuse employed in cellular networks
to obtain high spectral utilization.
The effect of interference on the performance
of multi-hop relay networks has not been
studied extensively in the literature. In this
work, we develop an analytical tool to study
the performance of a multi-hop transmission
Figure 1: Relay-assisted cellular network