RT Dissertation/Thesis
T1 Superimposed training for channel estimation in next-generation wireless multicarrier techniques
A1 Estrada Jiménez, Juan Carlos
AB In this thesis, we propose novel superimposed training (ST) techniques for channelestimation for future wireless systems for 5G and beyond. ST is a promising techniquethat permits to obtain channel state information in a way that it can provide higherspectral e_ciency compared with dedicated pilot proposals at the cost of increasingthe channel estimation error. In this context, a new proposal called partial-datasuperimposed training (PDST) is addressed for orthogonal frequency division multiplexing(OFDM) systems. The novelty of PDST is that incorporates an additionalpower control factor that, unlike previous proposals, allows to improve performancewith an accurate control of data and pilot interference. Based on this proposal thechannel estimation error is derived. The signal-to-interference and noise ratio (SINR)and average channel capacity are later introduced. The partial superimposition canovercome classical overlay schemes reducing the number of resources a_ected by thesuperimposition.Secondly, the channel estimation performance of a promising multicarrier techniqueknown as _lterbank multicarrier o_set quadrature amplitude modulation (FBMCOQAM)is evaluated. In this contribution, we model the introduction of a superimposedtraining sequence in an FBMC-OQAM system. Due to the superimpositionnew parameters appear in the formulation known as intrinsic interference and datainterference. An analytical expression for the channel estimation error, which _tswith the simulation results, is depicted. Then, the SINR and its average channelcapacity expressions are presented. Furthermore, the power allocation factor thatmaximizes the spectral e_ciency is found. It is shown that this proposal overcomesthe performance of FBMC-OQAM with pilot symbol assisted modulation (PSAM)and other multicarrier techniques as OFDM with PSAM and ST.Finally, the channel estimation in a promising technology known as visible lightcommunication (VLC) is analyzed. In this proposal, we model a VLC scenario whereST is used for channel estimation. The multicarrier technique DC-o_set OFDM istaken into account to adapt the electrical signal to the optical one. Then, multiple input single output (MISO) is considered to be used as the most adequate spatial multiplexingtechnique to work with VLC. In this novel technique an extensive analysisis done for deduction of the channel estimation error, SINR and spectral e_ciency.Simulation results validate the performance of each proposal in a quasi stationaryenvironment compared with PSAM-based channel estimation techniques.High spectral e_ciency and data rate can be expected of implementing theseproposals which successfully could satisfy the new data-rate requirements. All ofthese proposals consider multicarrier techniques and novel technologies to be used in5G and beyond systems thus o_ering new lines of investigation.
YR 2019
FD 2019-11
LK https://hdl.handle.net/10016/31745
UL https://hdl.handle.net/10016/31745
LA eng
NO Mención Internacional en el título de doctor
DS e-Archivo
RD 27 jul. 2024