2004 · 28 citations · 4 references
EngineeringElectrical EngineeringDigital CommunicationInformation TheoryWireless CommunicationsDiversity TechniquesModulationSpread Spectrum CommunicationWireless Channel ModelingBit Error RateBit-error Rate AnalysisDiversity CombiningDoppler SpreadFrequency Diversity
A novel frequency domain Doppler diversity technique for OFDM systems is proposed. The received OFDM signal is first frequency shifted to generate various diversity branches. After demodulation, branch outputs are individually weighted and added together. For Doppler spread signal, it alters fading statistics and improves the bit error rate. Extensive simulations show that combining three diversity branches with proper frequency shifts reduces BER by an order when the normalized Doppler spread is larger than 0.3.
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