Sökning: "error floor"
Visar resultat 1 - 5 av 29 avhandlingar innehållade orden error floor.
1. Bit-Wise Decoders for Coded Modulation and Broadcast Coded Slotted ALOHA
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
2. Error recovery support in manufacturing control systems
Sammanfattning : Instructing production equipment on a shop floor in mid 1990’s is still done using concepts from the 1950’s, although the electro-mechanical devices forming logical gates and memory cells are nowadays replaced by computers. The gates and memory cells are now presented in graphical editors, and there is support for defining new building blocks (gates) handling complex data as well as for advanced graphical monitoring of a production process. LÄS MER
3. On Reference Architectures for Development of Flexible Cell Control Systems
Sammanfattning : Industrial problems of inflexible and expensive shop-floor control systems were analysed. The principal causes are suggested to be poor development methodology, poor tools used for development and implementation, and poor knowledge on how such systems are best built. LÄS MER
4. Spatially Coupled Turbo-Like Codes
Sammanfattning : The focus of this thesis is on proposing and analyzing a powerful class of codes on graphs---with trellis constraints---that can simultaneously approach capacity and achieve very low error floor. In particular, we propose the concept of spatial coupling for turbo-like code (SC-TC) ensembles and investigate the impact of coupling on the performance of these codes. LÄS MER
5. Estimation of synchronization parameters
Sammanfattning : This thesis deals with the estimation of synchronization parameters in {Orthogonal Frequency Division Multiplexing} (OFDM) communication systems and in active ultrasonic measuring systems. Estimation methods for the timing and frequency offset and for the attenuation taps of the frequency selective channel are presented and investigated. LÄS MER