Abstract
This thesis foucus on how to design the pilot sequence and the channel estimation in Filter Bank-based Multicarrier systems. Filter Bank-based Multicarrier Modulation (FBMC) using Offset Quadrature Amplitude Modulation (OQAM), also named as FBMC/OQAM or OFDM/OQAM. FBMC/OQAM systems remove the Cyclic Prefix (CP), which reduces the spectrum efficiency in Cyclic Prefix-based Orthogonal Frequency Division Multiplexing (CPOFDM). To increase the spectrum efficiency, FBMC/OQAM systems use the synthesis filter bank (SFB) and analysis filter bank (AFB) at transmitter and receiver,respectively, instead of Cyclic Prefix. However, FBMC/OQAM suffers from an inherent (intrinsic) imaginary interference because of the filter bank. In other words, the orthogonality do not hold in the imaginary domain. So, a new channel estimation scheme is needed for FBMC/OQAM for high performance channel estimation. Therefore, in FBMC/OQAM systems, only realvalued symbols can be transmitted, in this paper we propose a new pilot sequence design we called “Interleaved Complex Pilot Decomposition (ICPD)”. ICPD cascades two identical zero-correlation zone (ZCZ) sequences in time domain, and after the fast Fourier transform (FFT) we decompose the complex-value into two real-valued (i.e., real- and imaginary- part). The feature of ICPD is that it interleave the real- and imaginary- part on the subcarriers to reduce the inter-carrier interference (ICI). The ICPD is a pilot sequence in frequency domain, we do the channel estimation in time domain to solve the necessity of the symbol interval is much longer than the maximum channel delay spread. The simulation of the proposedmethod is effective for FBMC/OQAM system. The performance of ICPD is conducted results show in the mean square error (MSE) and peak-to-average power ratio (PAPR).