A New Pilot Architecture for Sub-band Uplink OFDMA Systems

作者：Huang, Wei Chieh; Yang, Yi Syun; Li, Chih Peng^*

来源：IEEE Transactions on Broadcasting, 2013, 59(3): 461-470.

DOI：10.1109/TBC.2013.2252866

• Carrier frequency offset (CFO) estimation
• channel estimation
• multi-user interference (MUI)
• orthogonal frequency division multiple access (OFDMA)

In sub-band uplink orthogonal frequency division multiple access (OFDMA) systems, the data signals of the different users are transmitted on non-overlapping frequency sub-bands. Moreover, the pilots used to estimate the carrier frequency offset (CFO) and channel state are generally placed at the edge of each sub-band. However, the accuracies of the CFO and channel estimates are seriously degraded by multiple-user interference (MUI) between neighboring subscribers. Conventionally, the effects of MUI are mitigated by inserting a guard sub-carrier between adjacent users and adding a single pilot to either edge of the data sub-carrier. However, in the present study, the guard sub-carrier is more fully exploited by adding three pilots to each side of the data subcarrier. Notably, in the proposed approach, the pilots of neighboring users are overlapped. As a result, the proposed architecture has the same bandwidth efficiency as that of the conventional guard subcarrier insertion scheme. It is shown that the proposed pilot design yields a lower MUI than the conventional guard subcarrier insertion method and achieves an improved bit error rate (BER) performance as a result.

• 出版日期2013-9
• 单位中山大学