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In this paper,we consider a spectrum sharing cognitive radio network coexisting with a primary network.Particularly,the channel state information(CSI) between the secondary transmitter and the primary receiver is assumed to be outdated due to channel feedback latency.The secondary user(SU) is assumed to satisfy a given delay quality-of-service(QoS) constraint as well as the average interference power constraint.We aim to derive the maximum arrival rate of the SU under aforementioned constraints with the outdated CSI.In this respect,we derive the optimal power allocation to achieve the maximum effective capacity,and further derive the effective capacity.The closed-form expressions for the lower and upper bounds on the effective capacity are also derived.In addition,we obtain the effective capacities under two widely adopted adaptive transmission schemes,i.e.,optimal power and rate allocation(OPRA) and truncated channel inversion with fixed rate(TIFR).Numerical results are conducted to corroborate our studies.It is shown that the effective capacities of the SU under various transmission schemes are insensitive to the channel correlation coefficient especially under low channel correlation coefficient.It is also shown that the lower and upper bounds on the effective capacity are significantly tight under stringent delay QoS constraint.
In this paper, we consider a spectrum sharing cognitive radio network coexisting with a primary network. Particularly, the channel state information (CSI) between the secondary transmitter and the primary receiver is assumed to be outdated due to channel feedback latency. The secondary user ( SU) is assumed to satisfy a given delay quality-of-service (QoS) constraint as well as the average interference power constraint. We aim to derive the maximum arrival rate of the SU underSION constraints with the outdated CSI. In this respect, we derive the optimal power allocation to achieve the maximum effective capacity, and further derive the effective capacity. The closed-form expressions for the lower and upper bounds on the effective capacity are also derived. adapted adaptive transmission schemes, ie, optimal power and rate allocation (OPRA) and truncated channel inversion with fixed rate (TIFR) .Numerical results are conducted to c orroborate our studies. It is shown that the effective capacities of the SU under various transmission schemes are insensitive to the channel correlation coefficient especially under low channel correlation coefficient. It is also shown that the lower and upper bounds on the effective capacity are significantly tight under. stringent delay QoS constraint.