Abstract
In this paper, we consider a cooperative underlay cognitive radio system in which one secondary user (S) transmits its data to a secondary receiver with the assistance of multiple relays. In the considered underlay spectrum sharing scenario, the transmit power levers at S and forwarding relays are adjusted simultaneously according to a given threshold interference power that the primary user can tolerate. We also consider that relays adopt threshold decode-and-forward relay scheme and harvest energy from the primary transmitter with finite energy storage capacity under time switching scheme. Three best relay selection (RS) schemes, optimal source-relay link with wireless energy harvesting (WEH), optimal relay-destination link with WEH and optimal source-relay-destination link with WEH schemes, are proposed and studied. Closed-form analytical expressions for the outage probability of these three best RS schemes are derived, respectively. Finally, our analytical results are verified by Monte-Carlo simulations.
| Original language | English |
|---|---|
| Article number | 8680686 |
| Pages (from-to) | 358-369 |
| Number of pages | 12 |
| Journal | IEEE Transactions on Cognitive Communications and Networking |
| Volume | 5 |
| Issue number | 2 |
| DOIs | |
| Publication status | Published - Jun 2019 |
| Externally published | Yes |
Keywords
- Outage probability
- relay selection
- threshold decode-and-forward relay scheme
- underlay cognitive radio networks
- wireless energy harvesting