Figure 7From: GSM: gateway selection mechanism for strengthening inter-cluster coordination in cognitive radio ad hoc networksImpact of number of PUs on average number of inter-cluster control channels with different arrival rates. (a) σ = 0.1, (b) σ = 0.3, (c) σ = 0.5, (d) σ = 0.7, and (e) σ = 0.9.Back to article page