This dissertation is divided into two main topics. In the first topic, we study the
joint source-channel coding problem of transmitting an analog source over a Gaussian
channel in two cases - (i) the presence of interference known only to the transmitter and (ii) in the presence of side information about the source known only to the
receiver. We introduce hybrid digital analog forms of the Costa and Wyner-Ziv coding schemes. We present random coding based schemes in contrast to lattice based
schemes proposed by Kochman and Zamir. We also discuss superimposed digital and
analog schemes for the above problems which show that there are infinitely many
schemes for achieving the optimal distortion for these problems. This provides an
extension of the schemes proposed by Bross and others to the interference/source
side information case. The result of this study shows that the proposed hybrid digital analog schemes are more robust to a mismatch in channel signal-to-noise ratio
(SNR), than pure separate source coding followed by channel coding solutions. We
then discuss applications of the hybrid digital analog schemes for transmitting under
a channel SNR mismatch and for broadcasting a Gaussian source with bandwidth
compression. We also study applications of joint source-channel coding schemes for
a cognitive setup and also for the setup of transmitting an analog Gaussian source
over a Gaussian channel, in the presence of an eavesdropper.
In the next topic, we consider joint physical layer coding and network coding
solutions for bi-directional relaying. We consider a communication system where two transmitters wish to exchange information through a central relay. The transmitter
and relay nodes exchange data over synchronized, average power constrained additive
white Gaussian noise channels. We propose structured coding schemes using lattices
for this problem. We study two decoding approaches, namely lattice decoding and
minimum angle decoding. Both the decoding schemes can be shown to achieve the
upper bound at high SNRs. The proposed scheme can be thought of as a joint physical
layer, network layer code which outperforms other recently proposed analog network
coding schemes. We also study extensions of the bi-directional relay for the case with
asymmetric channel links and also for the multi-hop case. The result of this study
shows that structured coding schemes using lattices perform close to the upper bound
for the above communication system models.
| Identifer | oai:union.ndltd.org:tamu.edu/oai:repository.tamu.edu:1969.1/ETD-TAMU-2010-05-7915 |
| Date | 2010 May 1900 |
| Creators | John Wilson, Makesh Pravin |
| Contributors | Narayanan, Krishna R. |
| Source Sets | Texas A and M University |
| Language | en_US |
| Detected Language | English |
| Type | thesis, text |
| Format | application/pdf |
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