| Summary: | abstract: LTE-Advanced networks employ random access based on preambles
transmitted according to multi-channel slotted Aloha principles. The
random access is controlled through a limit <italic>W</italic> on the number of
transmission attempts and a timeout period for uniform backoff after a
collision. We model the LTE-Advanced random access system by formulating
the equilibrium condition for the ratio of the number of requests
successful within the permitted number of transmission attempts to those
successful in one attempt. We prove that for <italic>W</italic>≤8 there is only one
equilibrium operating point and for <italic>W</italic>≥9 there are three operating
points if the request load ρ is between load boundaries ρ<sub>1</sub>
and ρ<sub>2</sub>. We analytically identify these load boundaries as well as
the corresponding system operating points. We analyze the throughput and
delay of successful requests at the operating points and validate the
analytical results through simulations. Further, we generalize the
results using a steady-state equilibrium based approach and develop
models for single-channel and multi-channel systems, incorporating the
barring probability <italic>P<super>B</super></italic>. Ultimately, we identify the de-correlating
effect of parameters <italic>O, P<super>B</super>,</italic> and <italic>T<sub>o</sub><super>max</super></italic> and introduce the
Poissonization effect due to the backlogged requests in a slot. We
investigate the impact of Poissonization on different traffic and
conclude this thesis. === Dissertation/Thesis === Doctoral Dissertation Electrical Engineering 2014
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