SUB-BAND LOADING FOR PRE-EQUALIZED UPLINK OFDM-CDMA SYSTEMS

摘要

In this paper a new pre-equalization technique is presented for uplink OFDM-CDMA systems. All users employ spreading both in frequency (on sub-bands of the available spectrum) and time; moreover, bit and power loading is used at the mobile terminals to accomplish throughput maximization. The proposed loading algorithm, to avoid interference among users, inherently inverts the channel amplitude on the sub-carriers of each sub-band, while the phase is adjusted separately. Numerical results are given to highlight the effectiveness of the proposed scheme with respect to existing solutions.