Prefiltered Pisarenko frequency estimator for multiple real-valued sinusoids

An Infinite Impulse Response (IIR) notch filter based method is proposed for multiple real sinusoids frequency estimation. The estimator basically involves two steps. An initial frequency estimate is first obtained by solving the Least Squares (LS) equation based on the transversal part of the IIR filter. Based on the initial estimate, we introduce the recursive part and a LS cost function is then constructed from which the final estimate is acquired. Computer simulations show that the performance of the estimator approaches the Cramer-Rao Lower Bound for sufficiently high signal-to-noise ratios and/or data lengths.