Channel-independent non-data aided synchronization of generalized multiuser OFDM
نویسندگان
چکیده
We develop and analyze timing and carrier frequency offset synchronization algorithms for generalized asynchronous and quasisynchronous orthogonal frequency division multiple access systems using null subcarriers and subcarrier hopping. We derive an approximate analytic expression for the variance of the frequency offset estimators as a function of the number of active users and the SNR and show that the performance of our algorithms is asymptotically independent of the channel zero locations for quasisynchronous systems. Finally, we validate our theoretical expressions with simulations.
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