dc.contributor.advisor | Duman, Tolga Mete | |
dc.contributor.author | Herfeh, Mahdi Shakiba | |
dc.date.accessioned | 2019-11-21T10:32:35Z | |
dc.date.available | 2019-11-21T10:32:35Z | |
dc.date.copyright | 2019-11 | |
dc.date.issued | 2019-11 | |
dc.date.submitted | 2019-11-20 | |
dc.identifier.uri | http://hdl.handle.net/11693/52727 | |
dc.description | Cataloged from PDF version of article. | en_US |
dc.description | Thesis (Ph.D.): Bilkent University, Department of Electrical and Electronics Engineering, İhsan Doğramacı Bilkent University, 2019. | en_US |
dc.description | Includes bibliographical references (leaves 102-114). | en_US |
dc.description.abstract | As the number of wireless devices dramatically increases, they experience more
interference in their communications. As a result, managing interference in wireless
networks is an important challenge in future wireless communication systems,
which can be tackled in di erent layers of communications. Designing good channel
codes, which can enable reliable communication close to the information theoretic
limits in the presence of interference, is one of the ways to increase the
quality of service.
With the above motivation, in this research, we focus on code design for interference
channels (ICs). We, rst consider classical two-user fading IC and study
implementation of di erent encoding/decoding schemes with low-density paritycheck
(LDPC) codes for both quasi-static and fast fading scenarios. We adopt
the Han-Kobayashi (HK) type encoding, derive stability conditions on the degree
distributions of LDPC code ensembles, and obtain explicit and practical code
designs. In order to estimate the decoding thresholds, a modi ed form of the extrinsic
information transfer (EXIT) chart analysis based on binary erasure channel
(BEC) approximation for the incoming messages from the component LDPC
decoders to state nodes is developed. The proposed code design is employed in
several examples for both fast and quasi-static fading cases. A comprehensive set
of examples demonstrates that the designed codes perform close to the achievable
information theoretic limits. Furthermore, multiple antenna transmissions
employing the Alamouti scheme for fading ICs are studied; a special receiver
structure is developed, and speci c codes are explored. Finally, advantages of
the designed codes over point-to-point (P2P) optimal ones are demonstrated via
both asymptotic and nite block length simulations.
Next, we consider cognitive interference channels (CICs), a variant of classical
two-user ICs in which one of the transmitters (cognitive transmitter) has
non-causal knowledge of the other's (private user's) message. Prompted by the
information theoretical results, we design an explicit coding scheme for CIC in the
primary decodes cognitive regime. We present a novel joint decoder and design LDPC codes for our set-up. Simulation results demonstrate that the proposed
joint decoder and the designed codes outperform the conventional maximum ratio
combining type decoder and the point-to-point optimal codes, respectively.
Later, we propose and evaluate the idea of exible modulation for P2P communication
with available channel side information at the transmitter. This technique
does not perform as well as dirty paper coding (DPC); however, its simplicity is a
major advantage. Also the exible modulation technique shows more robustness
to inaccuracy in the channel state information. Finally, we consider a multiple
access channel (MAC) in which the non-causal knowledge of one of the users'
message is available at the other user. We consider both Gaussian channel and
fading scenarios. We propose the idea of joint encoding, and study its performance
via simulations demonstrating that the proposed approach outperforms
the classical coding scheme. | en_US |
dc.description.statementofresponsibility | by Mahdi Shakiba Herfeh | en_US |
dc.format.extent | xvi, 118 leaves : charts ; 30 cm. | en_US |
dc.language.iso | English | en_US |
dc.rights | info:eu-repo/semantics/openAccess | en_US |
dc.subject | Low-density parity-check codes | en_US |
dc.subject | Interference channels | en_US |
dc.subject | Code design | en_US |
dc.subject | Iterative joint decoding | en_US |
dc.subject | Han-Kobayashi encoding | en_US |
dc.subject | Multiuser systems | en_US |
dc.subject | Dirty paper coding | en_US |
dc.title | Code design for interference channels | en_US |
dc.title.alternative | Girişim kanalları için kod tasarımı | en_US |
dc.type | Thesis | en_US |
dc.department | Department of Electrical and Electronics Engineering | en_US |
dc.publisher | Bilkent University | en_US |
dc.description.degree | Ph.D. | en_US |
dc.identifier.itemid | B160008 | |