Fig. 6

Performance of successive interference cancellation. Here \(P/N=37\) dB and \(h_{1}=1\). The top curve ‘red line’ is the upper bound by evaluating \(0.5\log \left( 1+h_2^2\frac{P}{N}+h_1^2\frac{P}{N}\right)\). The markers ‘green asterisk’ and ‘blue plus’ are lower bounds for Discrete Modulated inputs with SIC. Similarly, The markers ‘green square box’ and ‘violet circle’ are lower bounds for Discrete Modulated inputs with 2 layers and TIN. In each scheme, the first marker is evaluated using a numerical bound and the latter is plotted with the analytical lower bound. The ‘black triangle’ marker is the rate with Gaussian Modulation as proposed in [24]