On the Efficient Estimation of the Frequency-Offset of a Noisy Sinusoid
S. Hineline, J Rothenberg Thomas · 2006
A low-complexity estimator (proposed by Kay) of the frequency offset of a sinusoid in proper complex white Gaussian noise is known to achieve the Cramer-Rao lower bound (CRLB) at signal to noise ratios (SNRs) beyond a certain threshold and for sufficiently low values of the frequencyoffset. Further, it is known that smoothing the observations can help lower this threshold at the expense of reducing the range of the resulting estimator. Based on this fact, the present work derives a frequency estimator which lowers the SNR-threshold that is necessary to achieve the CRLB. Comparedwith theonlyexistingobservationsmoothingfrequency estimator, the proposed one exhibits greater robustness in efficiency insofar as it achieves the CRLB at higher frequencyoffsetvalues, while still loweringtheSNR threshold required for such efficiency.