  In the linear minimum mean square error (LMMSE) estimation for orthogonal
frequency division multiplexing (OFDM) systems, the problem about the
determination of the algorithm's parameters, especially those related with
channel frequency response (CFR) correlation, has not been readily solved yet.
Although many approaches have been proposed to determine the statistic
parameters, it is hard to choose the best one within those approaches in the
design phase, since every approach has its own most suitable application
conditions and the real channel condition is unpredictable. In this paper, we
propose an enhance LMMSE estimation capable of selecting parameters by itself.
To this end, sampled noise MSE is first proposed to evaluate the practical
performance of interpolation. Based on this evaluation index, a novel parameter
comparison scheme is proposed to determine the parameters which can endow LMMSE
estimation best performance within a parameter set. After that, the structure
of the enhanced LMMSE is illustrated, and it is applied in OFDM systems.
Besides, the issues about theoretical analysis on accuracy of the parameter
comparison scheme, the parameter set design and algorithm complexity are
explained in detail. At last, our analyses and performance of the proposed
estimation method are demonstrated by simulation experiments.
