Grouping block

The grouping block determines the concurrent time-freque-ncy region of the desired signal using constraints (i) and (iii) in Table 1, and then reconstructs the segregated instantaneous amplitude and phase using the inverse wavelet transform [7]. $\hat{f}_1(t)$ and $\hat{f}_2(t)$ are the reconstructed f₁(t) and f₂(t). Constraint (i) is implemented by comparing the onset/offset ( $T_{k,\rm {on}},T_{k,\rm {off}}$) of X_k(t) with the onset/offset ( $T_{\rm {S}},T_{\rm {E}}$) of $X_{\hat{\ell}}(t)$ corresponding to F₀(t), where $\Delta T_{\rm {S}}=25$ msec and $\Delta T_{\rm {E}}=50$ msec [7]. Constraint (iii) is implemented by determining the channel number corresponding to the integer multiples of F₀(t).