Frequency synchronization for generalized OFDMA uplink

@inproceedings{citeulike:913138, abstract = {In orthogonal frequency division multiple access (OFDMA), the total spectral resource is partitioned into multiple orthogonal subcarriers. These subcarriers are assigned to different users for simultaneous transmission. OFDMA is very sensitive to frequency synchronization errors. In an unsynchronized OFDMA uplink, each user has a different carrier frequency offset (CFO) relative to the common uplink receiver. The orthogonality among subcarriers is thus destroyed resulting in multiple access interference as well as self interference. This problem is tackled in this paper by constructing the orthogonal spectral signals that would have been received if all users were frequency synchronized. A generalized OFDMA is described first considering arbitrary subcarrier assignments. A new signal model is formulated to characterize the interference on the generalized OFDMA uplink due to multiuser frequency synchronization errors. Least squares (LS) and minimum mean square error (MMSE) criteria are used to construct the orthogonal spectral signals from one received OFDMA block. An efficient implementation method is developed based on a banded matrix approximation, which is computationally inexpensive and provides good performance.}, author = {Cao, Zhongren and Tureli, U. and Yao, Yu-Dong and Honan, P. }, citeulike-article-id = {913138}, doi = {10.1109/GLOCOM.2004.1378122}, journal = {Global Telecommunications Conference, 2004. GLOBECOM '04. IEEE}, keywords = {frequency, ofdma, synchronization, uplink}, pages = {1071--1075 Vol.2}, posted-at = {2008-02-14 11:56:48}, priority = {2}, title = {Frequency synchronization for generalized OFDMA uplink}, url = {http://dx.doi.org/10.1109/GLOCOM.2004.1378122}, volume = {2}, year = {2004} }

TY - CONF ID - citeulike:913138 L3 - citeulike-article-id:913138 TI - Frequency synchronization for generalized OFDMA uplink JF - Global Telecommunications Conference, 2004. GLOBECOM '04. IEEE VL - 2 SP - 1071 EP - 1075 Vol.2 N2 - In orthogonal frequency division multiple access (OFDMA), the total spectral resource is partitioned into multiple orthogonal subcarriers. These subcarriers are assigned to different users for simultaneous transmission. OFDMA is very sensitive to frequency synchronization errors. In an unsynchronized OFDMA uplink, each user has a different carrier frequency offset (CFO) relative to the common uplink receiver. The orthogonality among subcarriers is thus destroyed resulting in multiple access interference as well as self interference. This problem is tackled in this paper by constructing the orthogonal spectral signals that would have been received if all users were frequency synchronized. A generalized OFDMA is described first considering arbitrary subcarrier assignments. A new signal model is formulated to characterize the interference on the generalized OFDMA uplink due to multiuser frequency synchronization errors. Least squares (LS) and minimum mean square error (MMSE) criteria are used to construct the orthogonal spectral signals from one received OFDMA block. An efficient implementation method is developed based on a banded matrix approximation, which is computationally inexpensive and provides good performance. KW - frequency KW - ofdma KW - synchronization KW - uplink AU - Cao, Zhongren AU - Tureli, U AU - Yao, Yu-Dong AU - Honan, P PY - 2004/// UR - http://dx.doi.org/10.1109/GLOCOM.2004.1378122 ER -