Slepian Function-Based Windowed OFDM Systems With High Mobility

In wireless communications with high mobility, conventional orthogonal frequency division multiplexing (OFDM) systems suffer high intercarrier interferences. For OFDM systems, considering the normalized Doppler frequency up to 1.333, we propose a Slepian function based enhanced window. Compared with the raised-cosine roll-off window, the Slepian window precisely confines its power within the desired frequency interval. For windowed OFDM systems, we also propose a low complexity interpolation based channel estimation scheme. Simulation results show that when frame-error-rate is <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$10^{-3}$ </tex-math></inline-formula>, the OFDM system using the Slepian window has about <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$2\sim 3$ </tex-math></inline-formula> dB performance gain over that using the raised-cosine roll-off window.