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Visar resultat 1 - 5 av 78 avhandlingar som matchar ovanstående sökkriterier.

1. 1. Mobile Satellite Broadcast and Multichannel Communications : analysis and design

   Författare :Cristoff Martin; Björn Ottersten; Jack Winters; KTH; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Signalbehandling; communications; satellite broadcast; mobile; MIMO; asymptotic analysis; spatial multiplexing; Signalbehandling; Signal processing; Signalbehandling;

   Sammanfattning : In this thesis, analytical analysis and design techniques for wireless communications with diversity are studied. The impact of impairments such as correlated fading is analyzed using statistical models. Countermeasures designed to overcome, or even exploit, such effects are proposed and examined. LÄS MER

3. 2. Group-Sparse Regression : With Applications in Spectral Analysis and Audio Signal Processing

   Författare :Ted Kronvall; Statistical Signal Processing Group; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; sparse regression; group-sparsity; statistical modeling; regularization; hyperparameter-selection; spectral analysis; audio signal processing; classification; localization; multi-pitch estimation; chroma; convex optimization; ADMM; cyclic coordinate descent; proximal gradient;

   Sammanfattning : This doctorate thesis focuses on sparse regression, a statistical modeling tool for selecting valuable predictors in underdetermined linear models. By imposing different constraints on the structure of the variable vector in the regression problem, one obtains estimates which have sparse supports, i.e. LÄS MER

4. 3. Spatial Spread of Organisms : Modeling ecological and epidemiological processes

   Författare :Tom Lindström; Uno Wennergren; Colleen Webb; Linköpings universitet; []
   Nyckelord :Spatial kernel; Spatially explicit modeling; Disease transmission; Animal movements; NATURAL SCIENCES; NATURVETENSKAP;

   Sammanfattning : This thesis focuses on the spread of organisms in both ecological and epidemiological contexts. In most of the studies presented, displacement is modeled with a spatial kernel function, which is characterized by scale and shape. These are measured by the net squared displacement (or kernel variance) and kurtosis, respectively. LÄS MER

5. 4. Multigrid Preconditioners for the Discontinuous Galerkin Spectral Element Method : Construction and Analysis

   Författare :Lea Miko Versbach; Numerisk analys; []
   Nyckelord :NATURVETENSKAP; NATURAL SCIENCES; Discontinuous Galerkin Method; Finite Volume Method; Implicit Schemes; Local Fourier Analysis; Multigrid Method; Preconditioner; Space-Time Discretization; Spectral Element Method;

   Sammanfattning : Discontinuous Galerkin (DG) methods offer a great potential for simulations of turbulent and wall bounded flows with complex geometries since these high-order schemes offer a great potential in handling eddies. Recently, space-time DG methods have become more popular. LÄS MER

7. 5. Baseband Processing for 5G and Beyond: Algorithms, VLSI Architectures, and Co-design

   Författare :Mojtaba Mahdavi; Institutionen för elektro- och informationsteknik; []
   Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; VLSI Implementation; Hardware architectures; ASIC implementation; FPGA implementation; CMOS Technology; Baseband Processing; Massive MIMO; 5G New Radio; Beyond 5G; Co-Design; FFT processor; OFDM modulation; wireless communications; Massive MIMO Detection; Angular domain processing; Zero forcing; Systolic array; Non-linear detector; Channel Sparsity; Channel compression; Linear detector; Channel coding; Spatial coupling; Turbo-like codes; Spatially coupled serially concatenated codes; Threshold analysis; Decoder architecture; BCJR algorithm; MAP algorithm; Coupling memory; Window decoding; Complexity analysis; Performance Evaluation; Throughput; Decoding Latency; Silicon area; Design tradeoffs; Interleaver architecture; Memory requirements; Matrix multiplication; Channel state information CSI ; Cholesky decomposition; Tanner graph; Trellis codes; Convolutional encoder; Code design; Puncturing; Reordering circuit; wireless communication system; digital electronic;

   Sammanfattning : In recent years the number of connected devices and the demand for high data-rates have been significantly increased. This enormous growth is more pronounced by the introduction of the Internet of things (IoT) in which several devices are interconnected to exchange data for various applications like smart homes and smart cities. LÄS MER