Adaptive scheme to determine the sub-carrier spacing for multi-carrier systems

摘要

Orthogonal Frequency Division Multiplexing (OFDM) is a typical multi-carrier technique that has been applied by many advanced wireless communication systems, e.g., 3GPP Long Term Evolution (LTE) and WiMAX. In order to support high mobility transmission, the sub-carrier spacing of multi-carrier systems is made large enough to overcome the Doppler frequency offset. However, this large sub-carrier spacing results in lower transmission efficiency since the CP (Cyclic Prefix) consumes a considerable of radio resources. The present invention provides an adaptive scheme to determine the sub-carrier spacing in which the default sub-carrier spacing is set to support lower mobility, while the adaptively adjusted sub-carrier spacing based on User Equipment (UE) mobile velocities is set to support higher mobility.