Frequency Estimation in OFDM Direct-Conversion Receivers Using a Repeated Preamble
نویسندگان
چکیده
منابع مشابه
Preamble-Assisted Estimation for Frequency-Dependent I/Q Mismatch in Direct-Conversion OFDM Receivers
In direct-conversion orthogonal frequency division multiplexing (OFDM) receivers, the impact of frequency-dependent I/Q mismatch (IQ-M) with carrier frequency offset (CFO) must be considered. A preamble-assisted estimation is developed to circumvent the frequencydependent IQ-M with CFO. The results of a simulation and an experiment show that the proposed method could provide good estimation eff...
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This paper proposes a preamble structure for joint estimation of carrier frequency offset (CFO) and I/Q imbalance. Because existing methods cannot guarantee correct solutions within all range of CFOs, we derive two constraints of phase rotations applied to repetition patterns. By using the preamble based on the presented constraints, CFO is optimally estimated, and I/Q imbalance estimation is p...
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ژورنال
عنوان ژورنال: IEEE Transactions on Communications
سال: 2016
ISSN: 0090-6778,1558-0857
DOI: 10.1109/tcomm.2016.2515083