Abstract:

Orthogonal frequency division multiplexing (OFDM) is a spectral efficient technique which benefits the highspeed transmission. In the highrate satelliteground data transmission system design, OFDM is very attractive since it helps solving the bandwidth resource issue. However, with the large dynamic character of the low earth orbit (LEO) satelliteground link, the data transmission signal suffers significant Doppler effects. Moreover, Doppler effects appear more complex for wideband OFDM. Merely considering frequency shift is inadequate. In this paper, we analyze the Doppler effect for wideband OFDM signals in the LEO satelliteground data transmission scenario. The paper models the LEO satelliteground data transmission link, and deduces the OFDM signal model in this large dynamic environment. Then, intersymbol interference (ISI) and interchannel interference brought by Doppler effects are quantified. The theoretical results are employed to analyze the OFDM system design requirement and design limitation for LEO satelliteground data transmission application.