IJBTT

Channel Estimation in OFDM Mobile Wireless Channel Using Pilot Sequences

	International Journal of Engineering Trends and Technology (IJETT)
	© 2013 by IJETT Journal
	Volume-4 Issue-3
	Year of Publication : 2013
	Authors : Vikas Kumar Batav , Brajlata Chourasiya

Citation 

Vikas Kumar Batav , Brajlata Chourasiya. "Channel Estimation in O FDM Mobile Wireless Channel Using Pilot Sequences". International Journal of Engineering Trends and Technology (IJETT). V4(3):489-492 Mar 2013. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group.

Abstract

Error free transmission is one of the main aims in wireless communications. With the increase in multimedia application, large amount of data is being transmitted over wireless communic ations. Due to the channel fading and the Doppler shifts caused by user mobility, a common problem in wireless systems, additional technologies are needed to combat multipath propagation fading and Doppler shifts. Time - variant channel estimation is one suc h crucial technique used to improve the performance of the modern wireless systems with Doppler spread and multipath spread. In this paper, we present the improved scheme of LS based channel estimation technique using block type pilot sequences. Channel es timation is done by estimating the time - varying channel frequency response for the OFDM symbols . The Least Square (LS) method is used for channel estimation technique using the block type pilot sequences. Time - variant channel estimation using pilot Sequenc es technique is a useful channel estimation technique in mobile wireless communication for accurately estimating transmitted information. The main advantage of pilot sequence is allowing more accurate representation of high mobility mobile wireles s channel s with low complexity. The MATLAB/SIMULINK Communication tool box is used for implement the proposed model. Due to channel interference, the accuracy of channel estimation is an essential factor for a good receiver design in order to exploit the full poten tial capacity of the OFDM systems. The main goal is to test the recently proposed method, time - variant channel estimation using pilot sequences.

References

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Keywords
Doppler Diversity, OFDM, Pilot Sequences, Channel Estimation, Least Square.