Sökning: "Noise suppression"
Visar resultat 11 - 15 av 72 avhandlingar innehållade orden Noise suppression.
11. Quantization and Noise-Shaped Coding for High Efficiency Transmitter Architectures
Sammanfattning : Three driving parameters in the development of transmitter technologies for wireless communication today is: energy efficiency, flexibility and footprint reduction. This thesis investigates the use of 1-bit oversampled signal representation, mainly as a power efficiency enhancement technique for the transmitter, but also as a path toward reduced footprint and increased flexibility. LÄS MER
12. Experimental Determination of Aeracoustic Sources in Low Mach Number Internal Flows
Sammanfattning : In this thesis, the in-duct experimental methods for determining aeroacoustic N-ports of in-duct elements are discussed and improved. The scattering matrix determination methods and the related wave decomposition methods are evaluated from measurements in an empty duct carrying a mean flow. LÄS MER
13. Generalized Bandpass Sampling Receivers for Software Defined Radio
Sammanfattning : Based on different sampling theorem, for example classic Shannon’s sampling theorem and Papoulis’ generalized sampling theorem, signals are processed by the sampling devices without loss of information. As an interface between radio receiver front-ends and digital signal processing blocks, sampling devices play a dominant role in digital radio communications. LÄS MER
14. Space-time processing and equalization for wireless communications
Sammanfattning : In this thesis several aspects of space-time processing and equalization for wire-less communications are treated. We discuss several different methods of improving estimates of space-time channels, such as temporal parametrization, spatial parametrization, reduced rank channel estimation, bootstrap channel estimation,and joint estimation of an FIR channel and an AR noise model. LÄS MER
15. Low-Power Low-Jitter Clock Generation and Distribution
Sammanfattning : Today’s microprocessors with millions of transistors perform high-complexitycomputing at multi-gigahertz clock frequencies. Clock generation and clockdistribution are crucial tasks which determine the overall performance of amicroprocessor. LÄS MER