TY - GEN
T1 - CFO estimation schemes for differential OFDM systems
AU - Xiang, Nian Zeng
AU - Ghrayeb, Ali
PY - 2009
Y1 - 2009
N2 - This paper proposes two blind carrier frequency offset (CFO) estimation schemes for differentially modulated orthogonal frequency division multiplexing (OFDM) systems. The proposed schemes estimate the fractional part of the CFO with only two consecutive OFDM blocks, and they exploit two implicit properties associated with differentially modulated OFDM (DOFDM) systems, i.e., the channel keeps constant over two consecutive OFDM blocks, and the DOFDM systems employ an M-ary phase-shift keying constellation. One of the schemes is based on the finite alphabet (FA) constraint and the other one is based on the constant modulus (CM) constraint. They provide a trade-off between the performance and computational complexity. Furthermore, the FA based scheme can achieve better performance at high signal-to-noise ratios at the expense of some additional computational complexity as compared to the existing CM based subspace scheme. The constrained Cramer-Rao lower bound is also derived. Several numerical examples are presented to validate the efficacy of the proposed schemes.
AB - This paper proposes two blind carrier frequency offset (CFO) estimation schemes for differentially modulated orthogonal frequency division multiplexing (OFDM) systems. The proposed schemes estimate the fractional part of the CFO with only two consecutive OFDM blocks, and they exploit two implicit properties associated with differentially modulated OFDM (DOFDM) systems, i.e., the channel keeps constant over two consecutive OFDM blocks, and the DOFDM systems employ an M-ary phase-shift keying constellation. One of the schemes is based on the finite alphabet (FA) constraint and the other one is based on the constant modulus (CM) constraint. They provide a trade-off between the performance and computational complexity. Furthermore, the FA based scheme can achieve better performance at high signal-to-noise ratios at the expense of some additional computational complexity as compared to the existing CM based subspace scheme. The constrained Cramer-Rao lower bound is also derived. Several numerical examples are presented to validate the efficacy of the proposed schemes.
UR - http://www.scopus.com/inward/record.url?scp=70449477210&partnerID=8YFLogxK
U2 - 10.1109/ICC.2009.5198814
DO - 10.1109/ICC.2009.5198814
M3 - Conference contribution
AN - SCOPUS:70449477210
SN - 9781424434350
T3 - IEEE International Conference on Communications
BT - Proceedings - 2009 IEEE International Conference on Communications, ICC 2009
T2 - 2009 IEEE International Conference on Communications, ICC 2009
Y2 - 14 June 2009 through 18 June 2009
ER -