Sökning: "Ana I. Pérez-Neira"
Hittade 3 avhandlingar innehållade orden Ana I. Pérez-Neira.
1. HARQ Systems: Resource Allocation, Feedback Error Protection, and Bits-to-Symbol Mappings
Sammanfattning : Reliability of data transmission is a fundamental problem in wireless communications. Fading in wireless channels causes the signal strength to vary at the receiver and this results in loss of data packets. To improve the reliability, automatic repeat request (ARQ) schemes were introduced. LÄS MER
2. Cross-layer Aspects in OFMDA Systems : Feedback, Scheduling and Beamforming
Sammanfattning : This thesis mainly studies the downlink of a wireless multiuser system, where the transmitter has limited knowledge about the communication channels of the users. Key techniques to improve the performance of such systems are, for instance, multiple antennas, multiuser diversity and orthogonal frequency-division multiple access (OFDMA). LÄS MER
3. Robust Transmit Signal Design and Channel Estimation for Multiantenna Systems
Sammanfattning : In the development of advanced signal processing techniques, dealing with both uncertainties and computational burden is essential. Taking the uncertainties into consideration is required in order to guarantee a certain level of performance, even when the system is designed based on imperfect prior knowledge. LÄS MER