الفهرس 
Filter Bank Multicarrier ModulationOnly 14 pages are availabe for public view
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Abstract
Filter bank multicarrier with offset quadrature amplitude modulation (FBMC/OQAM) system is one of the most attractive multicarrier choices for future wireless communications requirements. Prototype filters with smaller side lobes and faster spectrum decay are utilized with FBMC/OQAM, allowing it to have lower out-of-band energy and better spectral efficiency (SE) than classic multicarrier methods such as orthogonal frequency division multiplexing (OFDM). Further, because cyclic prefix (CP) is no longer used in FBMC/OQAM, all CP-related shortcomings have vanished. As FBMC/OQAM and OFDM are so similar, transitioning any OFDM-based technologies to FBMC/OQAM is rather easy.
Because FBMC/OQAM transmits real-valued data, the orthogonality condition is met in the real domain, resulting in an inherent damaging term known as intrinsic interference (II). The II complicates the channel estimation (CE) process by preventing traditional OFDM CE methods from being used directly with FBMC/OQAM. The two common approaches used in the FBMC/OQAM CE process are auxiliary pilot (AP) and data spreading, but both have some performance shortcomings.
In this thesis, the main research goal is to propose CE techniques for FBMC/OQAM systems that are capable of obtaining a better bit error rate (BER) performance with fewer mathematical operations, making them suitable for low-complexity technologies. The first proposed method “KalCod” employs a less massive data spreading approach to reduce the II effect, the least-squares (LS) is used to determine the initial channel coefficient .By applying Kalman filter (KF), a more precise instantaneous channel state information are obtained. The simulation results show that the proposed method “KalCod” outperforms the other existing CE methods in terms of throughput and BER performance while remaining within an acceptable range of complexity.
In the second proposed method ”Mod-KAP”, a modified KF with the help of an AP algorithm is developed to determine the channel. Based on the BER level BER =10-1.4, ”Mod-KAP” saves SNR by about 3 dB compared to the common methods used with FBMC/OQAM systems, till now. Besides the previous achievement, the used overhead symbols in ”Mod-KAP”, for CE purpose, is 50% less than the used in AP or coding methods.