Accounting for Link Outages We now relax the technical conditions ((6) and (7) for P1 and the two similar conditions for P2), and assume that any of the forward/reverse links may experience outage. In this case, the relation between χ∗ i and χ∗∗ i is not fixed (i.e., χ∗ i could be larger or smaller than χ∗∗ i ). The reason is that in the case of outage, if P2 operates in the FD mode, then U(FF) 1 may decrease faster with χ1 compared to U(FH) 1 , and hence the condition U(FF) 1 = U(HF) 1 may be satisfied before the condition U(FH) 1 = U(HH) 1 . Therefore, χ∗∗ 1 < χ∗ 1 (recall the definition of χ∗ 1 and χ∗∗ 1 in Section III-A). The same situation arises in the case of P2 when outage is likely to happen.