Stability analysis of the cognitive interference channel

A scenario with two single-user links, one licensed to use the spectral resource (primary) and one unlicensed (secondary), is considered (cognitive interference channel). In accordance to the cognitive radio principle, whereby the activity of the secondary link should not interfere with the performance of the primary, the unlicensed transmitter accesses the channel only when sensed idle. In this paper, the maximum stable throughput of the cognitive link (in packets/slot) is derived for a fixed throughput selected by the primary link by assuming: 1) sensing errors due to fading at the secondary link; 2) power allocation at the secondary transmitter based on long-term measurements.