The results are presented here in terms of a newly defined "Interference Index".
Since the instantaneous interference level I n may exceed the tolerable limit I n max, and violate the absolute interference constraint, we define the interference violation probability as Pr { I n > I n max }, where, Pr{A} denotes the probability of event A, which should be no larger than the value δ(p).
Since our goal is to jointly reduce reverberation and noise, we define the interference matrix boldsymbol{Phi}_{mathbf{u}} k,n) = boldsymbol{Phi}_{mathbf{d}} k,n) + boldsymbol{Phi}_{mathbf{v}} k,n).
Define an interference term, Z, as the total interference power at a UE during USFs from all the MBSs and the PBSs, excluding the MOI and the POI.
In order to define an interference threshold which is predetermined by a practical licensed system (considering the absence of a standard interference threshold for CR system, we have derived it using a tolerable capacity loss for the primary system), we assume that the received primary signal in PBS always has a desired " ".
The interference power thus simplifies to I = P ∑ n = 1 N H n. We now define the interference power gain which is denoted G as being the sum of the channel power gains between the interested user UT0 and the N interferers, i.e., G = ∑ n = 1 N H n = ∑ n = 1 N H pl, n H f, n H s, n.
We first define the interference model assumed in this paper.
A second possibility is to define the interference constraint by means of uncertainty sets [23, 24].
Similarly, we define the interference produced by user at any other cell as (4).
