Effective capacity analysis of link layer based on cognitive multiple access channel

This paper considers the effective capacity of multiple secondary users share spectrum with a primary user in a cognitive multiple access channel. Secondary users have to be subject to an interference power constraint for avoiding harmful interference inflicted on the primary user. In addition, the primary user and secondary users are restrained by the statistical quality of service (QoS). In this setting, we derive the closed-form effective capacity expressions for both the primary user and secondary users, and investigate the impact of the number of secondary users, QoS constraints, maximum interference power and the secondary users´ peak power constraint on the performance of the primary user and secondary users. The simulations show the tradeoff between the effective capacity of single secondary user and the number of secondary users for transmitting simultaneously as well as the total effective capacity of secondary users.