Jihwan P. Choi

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—This paper examines the detection problem of the preamble sequence index in the WiMAX system. The mobile station receiver knows all the possible preamble sequences and should estimate which preamble sequence has been transmitted from the base station. Since the preamble in the orthogonal frequency division multiplexing (OFDM) transmission is usually the(More)
MnBi has attracted much attention in recent years due to its potential as a rare-earth-free permanent magnet material. It is unique because its coercivity increases with increasing temperature, which makes it a good hard phase material for exchange coupling nanocomposite magnets. MnBi phase is difficult to obtain, partly because the reaction between Mn and(More)
— In this letter, we propose two simple OFDM mean delay estimation schemes, channel impulse response (CIR)-based and differential schemes, which are applicable for adaptive algorithms including improved channel estimation and fast handover. Instead of time-domain processing requiring additional inverse fast Fourier transform (IFFT), the mean delay can be(More)