IJBTT

Performance Evaluation of MMSE and LS Channel Estimation in OFDM System

	International Journal of Engineering Trends and Technology (IJETT)
	© 2014 by IJETT Journal
	Volume-15 Number-1
	Year of Publication : 2014
	Authors : Ajay Bahadur Singh , Vivek Kumar Gupta
	10.14445/22315381/IJETT-V15P209

Citation 

Ajay Bahadur Singh , Vivek Kumar Gupta. "Performance Evaluation of MMSE and LS Channel Estimation in OFDM System", International Journal of Engineering Trends and Technology (IJETT), V15(1),39-43 Sep 2014. ISSN:2231-5381. www.ijettjournal.org. published by seventh sense research group

Abstract

Since from last two decade Orthogonal Frequency Division Multiplexing (OFDM) got lots interest in mobile communication systems. In OFDM system, the radio channels which we use are frequency selective and vary with time for wireless wideband mobile communication system. The transfer function of these radio channels is unequal in time as well as in frequency domain, due to which a dynamic estimation of these channels should required at the demodulation point of OFDM. In this research work, we use Pilot-aided Least Square (LS) and Minimum Mean- Square Error (MMSE) estimator for estimating the channel of OFDM system with different modulation techniques i.e. 16-PSK, 4-QAM, 8-QAM,16-QAM. In simulation, we compare the performance of both estimators with proposed modulation schemes, which results that LS has preferred performance with low complexity while MMSE has best performance with one drawback i.e. it has high complexity.

References

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Keywords
OFMD, Communication Channel, MMSE, LS, PSK, and QAM