Distributed algorithm under cooperative or competitive priority users in cognitive networks

EURASIP Journal on Wireless Communications and Networking

Table 4 Two SUs access three available channels

	SU1	SU2	D_SU1(t)	D_SU2(t)	O_C1(t)	O_C2(t)	O_C3(t)
t=1	C1	C1	1	1	2	0	0
t=2	C2	C3	0	0	0	0	0
t=3	C2	C2	1	1	0	2	0
t=4	C3	C2	0	0	0	0	0
t=5	C3	C3	1	1	0	0	2
t=6	C1	C1	1	1	2	0	0

In this case, the total number of collisions for the two users is \(D(n) = \sum \limits _{k=1}^{U} D_{k}(n) = D_{SU1}(n) + D_{SU2}(n)\). The number of collisions in all channels produced by the users is \(O_{C}(n) = \sum \limits _{i=1}^{C} O_{i}(n)= O_{C1}(n)+ O_{C2}(n)+O_{C3}(n)\), while the number of collisions in the best channels, i.e., C1 and C2, is \(O_{U}(n)= \sum \limits _{k=1}^{U} O_{k}(n) = O_{C1}(n)+O_{C2}(n)\)