Embodiments include apparatuses, methods, and systems that may test a UE for its idle period distribution. A test system may identify a set of bins in which a union of the set of bins may be equal to a contention window, wherein each individual bin of the set of bins may have an associated probability. A first bin of the set of bins may have a first associated probability, and a second bin of the set of bins may have a second associated probability that is larger than the first associated probability. Each individual idle period may be assigned to a corresponding bin of the set of bins. A UE may have a pass status or a failure status based on the individual idle periods assigned to the corresponding bin of the set of bins, and the associated probability for the bin. Other embodiments may also be described and claimed.