Doppler dependent power control and sub-carrier allocation in OFDM multiple access systems

摘要

Digital data symbols from a transceiver are transmitted to at least two remote transceivers in a wireless communications system employing Orthogonal Frequency Division Multiplexing, wherein a number of available sub-carriers are shared between said remote transceivers. Information about magnitudes of Doppler effect experienced by the remote transceivers is provided; sub-carriers are allocated to each remote transceiver in dependence of the information about magnitudes of Doppler effect; and a power level transmitted to each of said remote transceivers is controlled in dependence of the information about magnitudes of Doppler effect. In this way the reception of OFDM signals for transceivers moving at high speed and thus experiencing a high Doppler effect is improved without degrading the reception quality for transceivers with low or no Doppler effect. Thus the performance of a system based on OFDM and multiple access is improved.