Fig. 1
From: Multi-tier dynamic sampling weak RF signal estimation theory
Instantaneous frequency \(f_{N=2}\) sampled with \(N_M = 4.1\) showing odd zero crossings (\(z=1\) and \(z=3\)): samples just before and just after the first zero crossing, \(n_{z=1,1,l=1}\), \(n_{z=1,2,l=1}\), first zero crossing sample estimate \(\tilde{n}_{N=2,z=1,l=1}\), samples just before and just after the third zero crossing, \(n_{z=3,1,l=1}\), \(n_{z=3,2,l=1}\), third zero crossing sample estimate \(\tilde{n}_{N=2,z=3,l=1}\). The red “x” indicate the estimated zero crossings obtained by linear interpolation between the sample times just before and just after the zero crossings