DocumentCode :
2949382
Title :
OFDM impairment mitigation techniques
Author :
Umasankar, Bharath ; Fernando, Xavier
Author_Institution :
Ryerson Univ., Toronto
fYear :
2007
fDate :
22-24 Aug. 2007
Firstpage :
1
Lastpage :
6
Abstract :
OFDM is an attractive option for high speed wired/wireless data transmission due to its inherent resistance to inter symbol interference (ISI). However, lack of frequency diversity makes it vulnerable to frequency selective impairments such as narrowband interference, frequency selective fading, frequency dependent attenuations etc. In this work, we describe a novel Adaptive Weighting (AW) technique as an efficient method to improve the BER performance of grouped linear constellation preceding (GLCP) OFDM which is used to achieve frequency diversity. In this method during maximum likelihood sequence detection (MLSD), the distance of the possible constellation points from the received symbols are weighted according to the SNR of each subcarrier before the sequence with the minimum distance is chosen. The proposed technique is shown to outperform previous GLCP-OFDM and GLCP-ACS (Adaptive Subcarrier Selection) OFDM over all SNR ranges at the expense of slightly increased complexity.
Keywords :
OFDM modulation; diversity reception; error statistics; fading; intersymbol interference; maximum likelihood detection; maximum likelihood sequence estimation; BER performance; OFDM impairment mitigation techniques; adaptive weighting technique; constellation points; frequency dependent attenuations; frequency diversity; frequency selective fading; frequency selective impairments; grouped linear constellation preceding OFDM; high speed wired-wireless data transmission; inter symbol interference; maximum likelihood sequence detection; narrowband interference; Attenuation; Bit error rate; Data communication; Fading; Frequency dependence; Frequency diversity; Intersymbol interference; Maximum likelihood detection; Narrowband; OFDM;
fLanguage :
English
Publisher :
ieee
Conference_Titel :
Access Networks & Workshops, 2007. AccessNets '07. Second International Conference on
Conference_Location :
Ottawa, Ont.
Print_ISBN :
978-1-4244-1150-4
Electronic_ISBN :
978-1-4244-1150-4
Type :
conf
DOI :
10.1109/ACCESSNETS.2007.4447139
Filename :
4447139
Link To Document :
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