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Bandwidth and rate allocation tradeoffs of source-channel coding, packetization and modulation in unequally protected multimedia communication systems

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  1. Tez No: 400327
  2. Yazar: ŞEFİK ŞUAYB ARSLAN
  3. Danışmanlar: PROF. PAMELA C. COSMAN, PROF. LAURENCE B. MILSTEIN
  4. Tez Türü: Doktora
  5. Konular: Elektrik ve Elektronik Mühendisliği, Electrical and Electronics Engineering
  6. Anahtar Kelimeler: Belirtilmemiş.
  7. Yıl: 2012
  8. Dil: İngilizce
  9. Üniversite: Unıversıty Of Calıfornıa San Dıego
  10. Enstitü: Yurtdışı Enstitü
  11. Ana Bilim Dalı: Elektrik Mühendisliği Ana Bilim Dalı
  12. Bilim Dalı: Belirtilmemiş.
  13. Sayfa Sayısı: Belirtilmemiş.

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Özet (Çeviri)

A conventional approach to the design of wireless multimedia communicationsis the layered approach, in which the network layers function independent of eachother. This kind of layered approach is inspired partly by Shannon?s separationtheorem in which the optimization of each block is equivalent to optimization of theoverall source-channel coding operation. However, the separation theorem is validonly in a point-to-point communication scenario in the case of asymptotically longblock lengths of data and assumes huge amounts of processing power and delay.Therefore, current practical communication systems strive to jointly design buildingblocks of a multimedia system for better performance. The focus of this dissertationis therefore to present various joint designs for different channel models and systems,although limited by physical constraints such as bandwidth, power and complexity.First, a robust coded scheme for progressive multimedia transmission is consideredfor an additive white Gaussian noise channel, a Rayleigh fading channel,and a frequency selective channel using in combination different unequal protectionmethods. We investigate the judicious use of the limited bandwidth throughthe combination and optimization of a progressive source coder, a rate compatiblepunctured convolutional code and a hierarchical modulation.Next, we investigate a novel packet formatting scheme for progressive sourcesusing interleavers and various channel codes. The source coder is combined with aconcatenated block coding mechanism to produce a robust transmission system forembedded bit streams. The objective is to create embedded codewords such that,for a particular information block, the necessary protection is obtained via multiplechannel codings, contrary to the conventional methods which use a single code rateper information block. We show that near?capacity performance can be achievedusing the proposed scheme in conjunction with low density parity check codes in abinary symmetric channel scenario.We finally focus on coding strategies for multimedia where the channel stateinformation is missing. A generalized Digital Fountain (DF) code is proposed toprovide efficient universal forward error correction solution for lossy packet networkswith increased unequal error protection and unequal recovery time properties. Wepropose a progressive source transmission system using this generalized code design.We apply the generalized DF code to a progressive source and show that it has betterunequal protection and recovery time properties than other published results.

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