Sökning: "OFDM modulation"
Visar resultat 1 - 5 av 29 avhandlingar innehållade orden OFDM modulation.
Sammanfattning : Despite shifting towards mm-wave bands, the sub-6 GHz band will continue to be a fundamental spectral band in 5G. However, the severe congestion in this band makes a well-constrained spectrum a critical requirementof 5G. LÄS MER
Sammanfattning : Aspects of modern communication systems is the overall theme of this thesis with emphasis placed on multicarrier modulation. The work considers four facets of such systems; namely duplexing design, interference mitigation, channel estimation and multiuser detection. LÄS MER
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
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
Sammanfattning : This thesis addresses the problem of designing a receiver for an Orthogonal FrequencyDivisionMultiplexing (OFDM)communication system operating over fading channels, taking into account the effects of hardware imperfections. We discuss solutions for efficiently estimating the parameters of a channel model and for compensating oscillator phase noise and analog to digital converter (ADC) quantisation errors at the receiver. LÄS MER