Sökning: "spectral coding"

Visar resultat 6 - 10 av 39 avhandlingar innehållade orden spectral coding.

  1. 6. Control and Communication with Signal-to-Noise Ratio Constraints

    Författare :Erik Johannesson; Institutionen för reglerteknik; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Real-time coding; SNR; Causal coding; AWN channel; AWGN channel; Remote source; Networked control; Control over channel; Convex optimization; Wiener filter;

    Sammanfattning : This thesis is about two problems in the intersection of communication and control theory. Their common feature is that they involve communication over an additive white noise channel with a signal-to-noise ratio (SNR) constraint. The first problem concerns the transmission of a real-valued signal from a partially observed Markov source. LÄS MER

  2. 7. Model Based Speech Enhancement and Coding

    Författare :David Yuheng Zhao; Bastiaan Kleijn; Peter Kabal; KTH; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; statistical model; Gaussian mixture mdel GMM ; hidden Markov model HMM ; moise reduction; Telecommunication; Telekommunikation;

    Sammanfattning : In mobile speech communication, adverse conditions, such as noisy acoustic environments and unreliable network connections, may severely degrade the intelligibility and natural- ness of the received speech quality, and increase the listening effort. This thesis focuses on countermeasures based on statistical signal processing techniques. LÄS MER

  3. 8. Multicarrier Modulation and Coding for Multichannel Systems

    Författare :Pål Frenger; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; multi-code DS-CDMA.; Decision directed coherent detection; RCPC-codes; Parallel combinatory signaling; rate matching; OFDM; multichannel systems; Channel estimation; Multicarrier modulation;

    Sammanfattning : In this thesis decision directed coherent detectors for single- and multicarriersystems employing an MMSE channel estimation technique is presented. Thedetectors are designed for Rayleigh fading channels and DQPSK or p/4-DQPSKmodulation and exploit knowledge of the fading process correlation. LÄS MER

  4. 9. From Modeling to Perception - Topics in Speech Coding

    Författare :Jan Skoglund; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : Transmission and storage of speech require an efficient representation of the speech signal. The conversion of the acoustic speech waveform into a suitable digital representation is called speech coding. This thesis consists of six papers contributing to different research areas in speech coding. LÄS MER

  5. 10. Adaptive Modulation and Coding in Wireless Communications with Feedback

    Författare :Sorour Falahati; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY;

    Sammanfattning : We study link adaptation techniques which are suitable for the future packet-based wireless communication systems, where in particular, flat Rayleigh fading channels are assumed. Firstly, an adaptive coding scheme based on Rate Compatible Convolutional (RCC) codes is proposed. LÄS MER