Sökning: "OFDM"

Visar resultat 11 - 15 av 77 avhandlingar innehållade ordet OFDM.

  1. 11. Contributions to Frequency Offset and Time Delay Estimation

    Författare :Mattias Olsson; Håkan Johansson; Jonny Holmberg; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; time delay estimation; OFDM; carrier frequency offset; Signal processing; Signalbehandling;

    Sammanfattning : The demand for reliable high rate and efficient communication is ever increasing. In this thesis we look at two different problems in such systems, and their possible solutions. LÄS MER

  3. 12. Contributions to Delay, Gain, and Offset Estimation

    Författare :Mattias Olsson; Håkan Johansson; Per Löwenborg; Markku Renfors; Linköpings universitet; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; time interleaved analog to digital conversion; delay estimation; OFDM; fractional delay filters; Signal processing; Signalbehandling;

    Sammanfattning : The demand for efficient and reliable high rate communication is ever increasing. In this thesis we study different challenges in such systems, and their possible solutions. LÄS MER

  4. 13. On 60GHz Wireless Communication Systems

    Författare :Maxime Flament; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; scenario; DQPSK; mm-wave; broadband; MMIC; propagation; interference; shadowing; OFDM; 4:th Generation Wireless 4GW ; mobile; 60 GHz;

    Sammanfattning : The consumer of the telecommunication services of tomorrow will expectto receive the same services in a wireless fashion as he today receivesfrom a fixed network. These services require reliable high data rate. LÄS MER

  5. 14. Multirate Codes and Multicarrier Modulation for Future Communication Systems

    Författare :Pål Frenger; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; channel estimation; code-spread CDMA; DS-CDMA; convolutional codes; interference cancellation; nested convolutional codes; multicarrier modulation; optimum distance spectrum ODS ; rate-compatible punctured convolutional codes RCPC-codes ; OFDM; turbo decoding; rate matching; parallel combinatory signaling; Rayleigh fading;

    Sammanfattning : In this thesis, new detection and modulation methods for multicarrier systems are presented. The proposed multicarrier detectors are based on feedback of previously detected symbols and the idea is to exploit the correlation, both in time between consecutive symbols, and in frequency between neighboring sub-carriers. LÄS MER

  7. 15. Turbo Codes and Channel Estimation in Wireless Systems

    Författare :Bartosz Mielczarek; Chalmers tekniska högskola; []
    Nyckelord :TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; adaptive coding; turbo codes; PSAM; timing offset; BCJR algorithm; synchronization; channel estimation; phase offset; Wiener filters; unequal error protection; OFDM;

    Sammanfattning : This thesis focuses on practical implementation issues of turbo codes with imperfectly estimated fading wireless channels and limited code length. Channel estimation can be divided into estimation of static parameters, such as constant timing and phase offset, and dynamic parameters, such as fading channel amplitudes. LÄS MER