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Abstract
This thesis focuses on channel estimation in a particular multi-carrier known as Orthogonal Frequency Division Multiplexing (OFDM), is expected to be widely used in the physical layer of future mobile less• communication systems. Chatmel estimation is one of the most . rtant issues in any wireless communication system, especially in the case uency selective fast fading channels.
First, . an overview is made on the nature of fading chatmels and their ations focusing on the important terminologies that are commonly overview on OFDM systems is then made. Following this, a survey ostcommonly used chatmel estimation techniques in OFDM systems . Following this, a complete simulation for an OFDM system is ~ The simulation is made in different enviromnents according to the 07 specifications. Furthermore, varying the OFDM system rs is taken into consideration. Different methods for estimating the are taken into consideration during simulation. After that, modified .estimation techniques using pilots are introduced. Their performance ted and compared with the performance of the existing techniques.
-, modified chatmel estimation technique that needs no pilots is . Simulation of the modified technique is performed and its hce is compared to one of the commonly used existing techniques.