Multiaccess and fading in communication networks
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001.
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| Format: | Thesis |
| Language: | eng |
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Massachusetts Institute of Technology
2005
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| Online Access: | http://hdl.handle.net/1721.1/16789 |
| _version_ | 1811093868332974080 |
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| author | Yeh, Edmund Meng, 1971- |
| author2 | Robert G. Gallager. |
| author_facet | Robert G. Gallager. Yeh, Edmund Meng, 1971- |
| author_sort | Yeh, Edmund Meng, 1971- |
| collection | MIT |
| description | Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001. |
| first_indexed | 2024-09-23T15:51:59Z |
| format | Thesis |
| id | mit-1721.1/16789 |
| institution | Massachusetts Institute of Technology |
| language | eng |
| last_indexed | 2024-09-23T15:51:59Z |
| publishDate | 2005 |
| publisher | Massachusetts Institute of Technology |
| record_format | dspace |
| spelling | mit-1721.1/167892019-04-12T08:50:31Z Multiaccess and fading in communication networks Yeh, Edmund Meng, 1971- Robert G. Gallager. Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. Massachusetts Institute of Technology. Dept. of Electrical Engineering and Computer Science. Electrical Engineering and Computer Science. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Electrical Engineering and Computer Science, 2001. Includes bibliographical references (p. 159-163). This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. Two fundamental issues in the design of wireless communication networks are the interference among multiple users and the time-varying nature of the fading wireless channel. We apply fundamental techniques in information theory and queueing theory to gain insights into the structure of these problems. In a terrestrial cellular or space network, multi-user interference arises naturally as different users in the same cell or region attempt to transmit to the base station or satellite at the same time and in the same frequency range. We first examine the impact of this interference on the design of error correction codes for reliable data transmission. At the physical layer of the wireless network, the phenomenon of multi-user interference is captured by the multiaccess (many-to-one) channel model. The set of all data rates at which reliable communication can take place over this channel is characterized via information theory by the so-called multiaccess capacity region. A basic problem is developing coding schemes of relatively low complexity to achieve all rates in this capacity region. By exploiting the underlying geometrical structure of the capacity region, we develop a method of reducing the multi-user coding problem to a set of single-user coding problems using the ideas of time-sharing and successive decoding. Next, we investigate the effect of multi-user interference on higher-layer quality-of-service issues such as packet delay. Under certain conditions of symmetry, we find that the structure of the multiaccess capacity region can again be used to obtain a "load-balancing" queue control strategy which minimizes average packet delay for Poisson data sources. (cont.) Due to the mobility of users and constantly changing multipath environments, wireless channels are inherently time-varying, or fading. Any sensible design of wireless networks must take into account the nature of this fading and the ability of the system to track channel variations. We consider a wireless system in which a single user sends time-sensitive data over a slowly varying channel. Information regarding the state of the channel is fed back with some delay to the transmitter, while the receiver decodes messages within some fixed and finite amount of time. Under these conditions, we demonstrate a provably optimal transmission strategy which maximizes the average data rate reliably sent across the wireless channel. The strategy is based on the information-theoretic idea of "successive refinement," whereby the decoder decodes at different rates according to the observed channel state. by Edmund Meng Yeh. Ph.D. 2005-05-19T14:35:54Z 2005-05-19T14:35:54Z 2001 2001 Thesis http://hdl.handle.net/1721.1/16789 50121074 eng M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 163 p. 771750 bytes 771450 bytes application/pdf application/pdf application/pdf Massachusetts Institute of Technology |
| spellingShingle | Electrical Engineering and Computer Science. Yeh, Edmund Meng, 1971- Multiaccess and fading in communication networks |
| title | Multiaccess and fading in communication networks |
| title_full | Multiaccess and fading in communication networks |
| title_fullStr | Multiaccess and fading in communication networks |
| title_full_unstemmed | Multiaccess and fading in communication networks |
| title_short | Multiaccess and fading in communication networks |
| title_sort | multiaccess and fading in communication networks |
| topic | Electrical Engineering and Computer Science. |
| url | http://hdl.handle.net/1721.1/16789 |
| work_keys_str_mv | AT yehedmundmeng1971 multiaccessandfadingincommunicationnetworks |