D. K. Lee and K. M. Chugg, “A Pragmatic Approach to Cooperative Communication,” in MILCOM 2006 – 2006 IEEE Military Communications conference, Oct. 2006, pp. 1–7. doi: 10.1109/MILCOM.2006.301987.
$z[k] = \sum_{n=1}^N A_{n,[k]} e^{j\Theta_n[k]} s[k] \quad = C[k] e^{j\Phi[k]} s[k]$