Transmit diversity usually employs multiple antennas at the transmitter. However, many
wireless devices such as mobile cellphones, Personal Digital Assistants (PDAs), just to name
a few, are limited by size, hardware complexity, power and other constraints to just one
antenna. A new paradigm called cooperative communication which allows single antenna
mobiles in a multi-user scenario to share their antennas has been proposed lately. This
multi-user configuration generates a virtual Multiple-Input Multiple-Output system, leading
to transmit diversity. The basic approach to cooperation is for two single-antenna users to use
each other's antenna as a relay in which each of the users achieves diversity. Previous
cooperative signaling methods encompass diverse forms of repetition of the data transmitted
by the partner to the destination. A new scheme called coded cooperation [15] which
integrates user cooperation with channel coding has also been proposed. This method
maintains the same code rate, bandwidth and transmit power as a similar non-cooperative
system, but performs much better than previous signaling methods [13], [14] under various
inter-user channel qualities.
This dissertation first discusses the coded cooperation framework that has been proposed
lately [19], coded cooperation with Repeat Convolutional Punctured Codes (RCPC) codes
and then investigates the application of turbo codes in coded cooperation.
In this dissertation we propose two new cooperative diversity schemes which are the
Repeat-Punctured Turbo Coded cooperation and coded cooperation using a Modified
Repeat-Punctured Turbo Codes. Prior to that, Repeat-Punctured Turbo codes are introduced.
We characterize the performance of the two new schemes by developing the analytical bounds
for bit error rate, which is confirmed by computer simulations. Finally, the turbo coded
cooperation using the Forced Symbol Method (FSM) is presented and validated through
computer simulations under various inter-user Signal-to-Noise Ratios (SNRs). / Thesis (M.Sc.Eng.)-University of KwaZulu-Natal, 2008.
| Identifer | oai:union.ndltd.org:netd.ac.za/oai:union.ndltd.org:ukzn/oai:http://researchspace.ukzn.ac.za:10413/822 |
| Date | 01 September 2010 |
| Source Sets | South African National ETD Portal |
| Language | English |
| Detected Language | English |
| Type | Thesis |
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