Frequency domain concurrent channel equalization for multicarrier systems
Receivers for wireless Orthogonal Frequency Division Multiplexing (OFDM) systems usually perform the channel estimation based on pilot carriers in known positions of the channel spectrum. Interpolation between pilot carriers is applied to determine the channel transfer function in all carrier frequencies. Channel variations along time are compensated by means of interpolation between successive channel estimates on the same carrier frequency. However, not rarely, the fast channel variations exceed the time interpolator capability, as is the case for mobile operation. In this article we present a new channel compensation technique based on the concurrent operation of two stochastic gradient time-domain algorithms, one which minimizes a cost function that measures the received signal energy dispersion and other which minimizes the Euclidean distance between the received digital modulation symbols and the ones in the reference constellation assigned to each OFDM sub-channel. Results show that the new technique advantageously improves the system robustness to fast channel variations since, with a low computational cost, it dramatically reduces the demodulator symbol error rate even when the receiver is operating in an intense dynamic multipath scenario.
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Sociedade Brasileira de Computação
2007
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oai:scielo:S0104-650020070001000022010-05-21Frequency domain concurrent channel equalization for multicarrier systemsD'Agostini,FábioCarboni Júnior,SirlesioCastro,Maria C. F. deCastro,Fernando C. C. de Concurrent Equalization Broadcast Modulation Pilots Multicarrier Receivers for wireless Orthogonal Frequency Division Multiplexing (OFDM) systems usually perform the channel estimation based on pilot carriers in known positions of the channel spectrum. Interpolation between pilot carriers is applied to determine the channel transfer function in all carrier frequencies. Channel variations along time are compensated by means of interpolation between successive channel estimates on the same carrier frequency. However, not rarely, the fast channel variations exceed the time interpolator capability, as is the case for mobile operation. In this article we present a new channel compensation technique based on the concurrent operation of two stochastic gradient time-domain algorithms, one which minimizes a cost function that measures the received signal energy dispersion and other which minimizes the Euclidean distance between the received digital modulation symbols and the ones in the reference constellation assigned to each OFDM sub-channel. Results show that the new technique advantageously improves the system robustness to fast channel variations since, with a low computational cost, it dramatically reduces the demodulator symbol error rate even when the receiver is operating in an intense dynamic multipath scenario.info:eu-repo/semantics/openAccessSociedade Brasileira de ComputaçãoJournal of the Brazilian Computer Society v.12 n.4 20072007-03-01info:eu-repo/semantics/articletext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0104-65002007000100002en10.1590/S0104-65002007000100002 |
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D'Agostini,Fábio Carboni Júnior,Sirlesio Castro,Maria C. F. de Castro,Fernando C. C. de |
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D'Agostini,Fábio Carboni Júnior,Sirlesio Castro,Maria C. F. de Castro,Fernando C. C. de Frequency domain concurrent channel equalization for multicarrier systems |
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D'Agostini,Fábio Carboni Júnior,Sirlesio Castro,Maria C. F. de Castro,Fernando C. C. de |
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D'Agostini,Fábio |
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Frequency domain concurrent channel equalization for multicarrier systems |
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Frequency domain concurrent channel equalization for multicarrier systems |
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Frequency domain concurrent channel equalization for multicarrier systems |
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Frequency domain concurrent channel equalization for multicarrier systems |
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Frequency domain concurrent channel equalization for multicarrier systems |
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frequency domain concurrent channel equalization for multicarrier systems |
description |
Receivers for wireless Orthogonal Frequency Division Multiplexing (OFDM) systems usually perform the channel estimation based on pilot carriers in known positions of the channel spectrum. Interpolation between pilot carriers is applied to determine the channel transfer function in all carrier frequencies. Channel variations along time are compensated by means of interpolation between successive channel estimates on the same carrier frequency. However, not rarely, the fast channel variations exceed the time interpolator capability, as is the case for mobile operation. In this article we present a new channel compensation technique based on the concurrent operation of two stochastic gradient time-domain algorithms, one which minimizes a cost function that measures the received signal energy dispersion and other which minimizes the Euclidean distance between the received digital modulation symbols and the ones in the reference constellation assigned to each OFDM sub-channel. Results show that the new technique advantageously improves the system robustness to fast channel variations since, with a low computational cost, it dramatically reduces the demodulator symbol error rate even when the receiver is operating in an intense dynamic multipath scenario. |
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Sociedade Brasileira de Computação |
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2007 |
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http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0104-65002007000100002 |
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AT dagostinifabio frequencydomainconcurrentchannelequalizationformulticarriersystems AT carbonijuniorsirlesio frequencydomainconcurrentchannelequalizationformulticarriersystems AT castromariacfde frequencydomainconcurrentchannelequalizationformulticarriersystems AT castrofernandoccde frequencydomainconcurrentchannelequalizationformulticarriersystems |
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1756411103950143488 |