We consider an asynchronous bi-directional relay network, consisting of two singleantenna
transceivers and multiple single-antenna relays, where the transceiver-relay
paths are subject to different relaying and/or propagation delays. Such a network can
be viewed as a multipath channel which can cause inter-symbol-interference (ISI) in
the signals received by the two transceivers. Hence, we model such a communication
scheme as a frequency selective multipath channel which produces ISI at the two
transceivers, when the data rates are relatively high. We study both multi- and
single-carrier communication schemes in such networks.
In a multi-carrier communication scheme, to tackle ISI, the transceivers employ
an orthogonal frequency division multiplexing (OFDM) scheme to diagonalize the
end-to-end channel. The relays use simple amplify-and-forward relaying, thereby
materializing a distributed beamformer. For such a scheme, we propose two different
algorithms, based on the max-min fair design approach, to calculate the subcarrier
power loading at the transceivers as well as the relay beamforming weights.
In a single-carrier communication, assuming a block transmission/reception scheme,
block channel equalization is used at the both transceivers to combat the inter-blockinterference
(IBI). Assuming a limited total transmit power budget, we minimize
the total mean squared error (MSE) of the estimated received signals at the both
transceivers by optimally obtaining the transceivers??? powers and the relay beamforming
weight vector as well as the block channel equalizers at the two transceivers.
| Identifer | oai:union.ndltd.org:LACETR/oai:collectionscanada.gc.ca:OOSHDU.10155/430 |
| Date | 01 February 2014 |
| Creators | Vahidnia, Reza |
| Contributors | Shahbazpanahi, Shahram |
| Source Sets | Library and Archives Canada ETDs Repository / Centre d'archives des thèses électroniques de Bibliothèque et Archives Canada |
| Language | English |
| Detected Language | English |
| Type | Dissertation |
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