Table 6 The computation cost of the t th iteration in DCS-SOMP

(1) ${\lambda }_t={arg\; max}_{j=1,...,N}\sum _{l=1}^L\left|⟨{\mathbf{r}}_{l,t-1},{\phi }_j⟩\right|.$

LpM(N-t+1)

-

(2) a _t = Φ _t z _t

LpMt

-

(3) z _t = arg min _z ||y-Φ _t z_t-1||₂

-

L(ℓ₂ optimization for t variables)

Total

Lp(MN+M)

L(ℓ₂ optimization for t variables)