Search for dissertations about: "OFDM modulation"

Showing result 11 - 15 of 32 swedish dissertations containing the words OFDM modulation.

2. 11. Modulation and channel effects in digital communication

   Author : Sara Sandberg; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Signalbehandling; Signal Processing;

   Abstract : This thesis investigates three possible methods to increase the performance of digital communication systems, with focus on wireless systems, by accounting for some of the channel effects that may occur. The modulation scheme plays an important role in the impact of different channel effects on system performance and this work considers both a single-carrier system and orthogonal frequency-division multiplexing (OFDM). READ MORE

4. 12. Adaptation in multiple input multiple output systems with channel state information at transmitter

   Author : Jinliang Huang; Svante Signell; Anders Ahlén; KTH; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; MIMO; adaptive modulation; power allocation; spectral efficiency; CSI; Electrical engineering; Elektroteknik;

   Abstract : This thesis comprises two parts: the first part presents channel-adaptive techniques to achieve high spectral efficiency in a single user multiple-input multiple-output (MIMO) system; the second part exhibits a programmable and reconfigurable software-defined-radio orkbench(SDR-WB) in the Matlab/Octave environment that accommodates a variety of wireless applications. In an attempt to achieve high spectral efficiency, an adaptive modulation technique is applied at the transmitter to vary the data rate depending on the channel state information (CSI). READ MORE

5. 13. Physical Layer Techniques for High Frequency Wireline Broadband Systems

   Author : Eduardo Lins de Medeiros; Bredbandskommunikation; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Digital Subscriber Line; Multicarrier Modulation; Vectoring; Copper cables; Radio-over-Copper;

   Abstract : This thesis collects contributions to wireline and wireless communication systems with an emphasis on multiuser and multicarrier physical layer technology. To deliver increased capacity, modern wireline access systems such as G.fast extend the signal bandwidth up from tens to hundreds of MHz. READ MORE

6. 14. Design and analysis of estimators for multicarrier modulation and ultrasonic imaging

   Author : Magnus Sandell; Luleå tekniska universitet; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; Signalbehandling; Signal Processing;

   Abstract : This thesis deals with two areas: multicarrier modulation and ultrasonic imaging. Although different in application, these fields have a lot in common. For instance, synchronization and channel estimation in communication systems correspond to time-delay estimation and system identification in ultrasonic imaging. READ MORE

7. 15. Diversity and Interference Aspects in the Downlink of Code Division Multiple Access Systems

   Author : Anders Persson; Chalmers tekniska högskola; []
   Keywords : TEKNIK OCH TEKNOLOGIER; ENGINEERING AND TECHNOLOGY; orthogonal frequency division multiplexing; multi-carrier modulation; Rayleigh-fading channels; code division multiple access; frequency-selective channels; multiple access interference; diversity;

   Abstract : This thesis consists of six included papers and technical reports, plus an introduction. The topic studied is interference and diversity aspects in code division multiple access (CDMA) systems for mobile cellular communications. The focus in the papers is on the downlink - the communication link from the base station to the mobile terminal. READ MORE