The TN will not transmit in the current resource block, due to BPC, otherwise, Case 2. The user data distributed from the CU to TN n is lost.
The algorithm accommodates the activity windows according to the depth of the CHs, so that information can move forward in every activity window to a node that has not had yet a chance to transmit in the current cycle.
In case of the CS scheme, it is possible that the TN will not transmit in the current resource block even if CSI sharing is not affected by the failure of control channels.
When a station has a frame to transmit, it attempts to transmit with probability p. If k stations are transmitting in the current slot, then the success probability D k in the next time slot is begin{array}rcl@ D_{k} = Kp 1-p)^{L-1}, end{array}.
In other words, when all the existing femto-BSs (except those who are inside the macro users' exclusion regions) pick the same RB as the tagged femto (p RB = 1) and when they all have data to transmit in the current time slot (p tx = 1), the tagged femto user will experience the maximum value for the outage probability derived for different SINR targets.
Regarding the assignment of activity windows to the clusters, described in Section 3.4, we chose a staggered approach according to the depth of the cluster heads (CHs), so that information can move forward in every activity window to a node that has not had yet a chance to transmit in the current cycle.
For the femto network, the aggregate interference results only from the other femto-BSs that (1) pick the same RB as the tagged femto, (2) are allowed to transmit in the current time slot, and (3) are not inside the macro users' exclusion regions.
That is, a conservative yielding mechanism of the high-priority link allows for the low-priority link to be scheduled opportunistically, only whenever the high-priority link can reduce its own data rate for the packet to transmit in the current slot.
