In the underlay spectrum sharing approach, cognitive radios have limited coverage area to
keep interference protection for the licensed users. Multiple cooperative relays have shown …

In this paper, two optimal power allocation strategies for hybrid interweave-underlay
cognitive cooperative radio networks (CCRNs) are proposed to maximize channel capacity …

For cognitive relay networks coexisting with multiple primary transceivers, we investigate the
secondary system performance using outdated channel state information (CSI). We propose …

This paper investigates the performance of Multisource Multirelay Cognitive Radio Network
(MMCRN). Underlay spectrum sharing is used to achieve efficient spectrum utilization while …

Although underlay spectrum sharing has been shown as a promising technique to promote
the spectrum utilization in cognitive radio networks (CRNs), it may suffer bad secondary …

With the wide‐spread wireless applications and services, the spectrum scarcity has become
a challenging problem. Thus, it is necessary to find a solution to have more spectrum bands …

In the underlay decode-and-forward (DaF) cooperative cognitive radio (CR) network, an
optimal relay can be selected by the conventional max-min selection on the condition of not …

Cognitive radio (CR) systems allow unlicensed secondary users to transmit on the licensed
frequency bands without degrading the transmissions of licensed primary users. Combining …

In this paper, we study a hybrid interweave-underlay spectrum access system that integrates
amplify-and-forward relaying. In hybrid spectrum access, the secondary users flexibly switch …

Spectrum sharing in cognitive radio network helps to improve the spectrum utilization. In
underlay spectrum sharing model, the secondary users (SU) are allowed to share the …