A subspace framework for fast parameter estimation with known waveforms
B.E. Freburger, D.W. Tufts, Thomas A. Palka · 2002
An efficient scheme for implementing a search of a likelihood function of known form at moderate to high SNR is constructed. Often, the original function to be searched is ill behaved with many local extreme points. By projecting the signal onto a subspace of replica waveforms we first find the maximum of a related function that is more well behaved, and then follow with a local search on the original function. The approach builds on a method of estimation of the time delay of a narrowband signal, and it can be used to improve the efficiency of fast maximum likelihood estimation.