Case 1 $$1+\frac {{\beta _{a}^{2}}[k]|h_{\text {ad}}[k]|^{2}P}{N}$$ $$1+\frac {{\beta _{a}^{2}}[k]|h_{\text {ad}}[k]|^{2}P}{N}$$ $$1+\frac {{\beta _{b}^{2}}[k]|h_{\text {bd}}[k]|^{2}P}{N+{\beta _{a}^{2}}[k]|h_{\text {ad}}[k]|^{2}P}$$ $$1+\frac {{\beta _{b}^{2}}[k]|h_{\text {bd}}[k]|^{2}P}{N+{\beta _{a}^{2}}[k]|h_{\text {ad}}[k]|^{2}P}$$
Case 2 $$1+\frac {{\beta _{a}^{2}}[k]|h_{\text {ad}}[k]|^{2}P}{N}$$ $$1+\frac {{\beta _{a}^{2}}[k]|h_{\text {ad}}[k]|^{2}P}{N}$$ $$1+\frac {{\beta _{b}^{2}}[k]|h_{\text {br}}[k]|^{2}P}{N+{\beta _{a}^{2}}[k]|h_{\text {ar}}[k]|^{2}P}$$ $$1+\frac {{\beta _{b}^{2}}[k]|h_{\text {bd}}[k]|^{2}P}{N+{\beta _{a}^{2}}[k]|h_{\text {ad}}[k]|^{2}P}$$
$$+\frac {\beta _{\text {br}}^{2}[k]|h_{\text {rd}}[k]|^{2}P}{N}$$
Case 3 $$1+\frac {{\beta _{a}^{2}}[k]|h_{\text {ar}}[k]|^{2}P}{N}$$ $$1+\frac {{\beta _{a}^{2}}[k]|h_{\text {ad}}[k]|^{2}P}{N}$$ $$1+\frac {{\beta _{b}^{2}}[k]|h_{\text {br}}[k]|^{2}P}{N+{\beta _{a}^{2}}[k]|h_{\text {ar}}[k]|^{2}P}$$ 1+snr b [k]
$$+ \frac {\beta _{\text {ar}}^{2}[k]|h_{\text {rd}}[k]|^{2}P}{N}$$
Case 4 $$1+\frac {{\beta _{a}^{2}}[k]|h_{\text {ar}}[k]|^{2}P}{N+{\beta _{b}^{2}}[k]|h_{\text {br}}[k]|^{2}P}$$ $$1+\frac {{\beta _{a}^{2}}[k]|h_{\text {ad}}[k]|^{2}P}{N}$$ $$1+\frac {{\beta _{b}^{2}}[k]|h_{\text {br}}[k]|^{2}P}{N}$$ 1+snr b [k]
$$+ \frac {\beta _{\text {ar}}^{2}[k]|h_{\text {rd}}[k]|^{2}P}{N}$$