Sökning: "Transmission error"

Visar resultat 36 - 40 av 192 avhandlingar innehållade orden Transmission error.

1. 36. On error-robust source coding with image coding applications

   Författare :Tomas Andersson; Mikael Skoglund; Astrid Lundmark; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; source coding; channel coding; joint source-channel coding; multiple description coding; image coding; vector quantization; channel optimized vector quantization; Telecommunication; Telekommunikation;

   Sammanfattning : This thesis treats the problem of source coding in situations where the encoded data is subject to errors. The typical scenario is a communication system, where source data such as speech or images should be transmitted from one point to another. A problem is that most communication systems introduce some sort of error in the transmission. LÄS MER

3. 37. Coding and Modulation for Wideband CDMA

   Författare :Ola Wintzell; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; turbo codes.; Electronics and Electrical technology; channel coding; impulse radio; coordinated transmission; pre-coding; cellular radio capacity; Direct sequence code division multiple access DS-CDMA ; pulse position hopped code division multiple access PPH-CDMA ; Elektronik och elektroteknik; Telecommunication engineering; Telekommunikationsteknik;

   Sammanfattning : Wideband CDMA (Code Division Multiple Access) is one of the key technologies for future mobile communication systems. This thesis studies various coding and transmission methods for wideband CDMA communications. In a cellular environment, the system performance depends on the interference from other cells. LÄS MER

4. 38. Bit-Wise Decoders for Coded Modulation and Broadcast Coded Slotted ALOHA

   Författare :Mikhail Ivanov; Chalmers tekniska högskola; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; mutual information; vehicular communications; bit-interleaved coded modulation; error floor; slotted ALOHA; medium access control; All-to-all broadcast;

   Sammanfattning : This thesis deals with two aspects of wireless communications. The first aspect is about efficient point-to-point data transmission. To achieve high spectral efficiency, coded modulation, which is a concatenation of higher order modulation with error correction coding, is used. LÄS MER

5. 39. Fast-Neutron Tomography using a Mobile Neutron Generator for Assessment of Steam-Water Distributions in Two-Phase Flows

   Författare :Peter Andersson; Staffan Jacobsson Svärd; Henrik Sjöstrand; Stephan Pomp; Ane Håkansson; Michael Österlund; Bernhard Ludewigt; Uppsala universitet; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Void distribution; neutron tomography; plastic scintillator; transmission measurements; neutron detection; Applied Nuclear Physics; Tillämpad kärnfysik;

   Sammanfattning : This thesis describes the measurement technique of fast-neutron tomography for assessing spatial distributions of steam and water in two-phase flows. This so-called void distribution is of importance both for safe operation and for efficient use of the fuel in light water reactors, which compose the majority of the world’s commercial nuclear reactors. LÄS MER

7. 40. Non-intrusive Methods for Mode Estimation in Power Systems using Synchrophasors

   Författare :Vedran Peric; Luigi Vanfretti; Xavier Bombois; Cristian Rojas; Mani V. Venkatasubramanian; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Synchrophasors; Phasor measurement units; system identification; mode estimation; electromechanical oscillations; prediction error; signal selection; experiment design; probing; Electrical Engineering; Elektro- och systemteknik;

   Sammanfattning : Real-time monitoring of electromechanical oscillations is of great significance for power system operators; to this aim, software solutions (algorithms) that use synchrophasor measurements have been developed for this purpose. This thesis investigates different approaches for improving mode estimation process by offering new methods and deepening the understanding of different stages in the mode estimation process. LÄS MER