TY - JOUR
T1 - Diversity-multiplexing tradeoff in selective cooperation for cognitive radio
AU - Zou, Yulong
AU - Yao, Yu Dong
AU - Zheng, Baoyu
PY - 2012
Y1 - 2012
N2 - In this paper, we first explore a selective cooperation framework for secondary user transmissions in a cognitive radio network with single relay. In the selective cooperation framework, two transmission modes (i.e., relay diversity transmission and non-relay direct transmission) are considered. We study two specific selective cooperation schemes with and without an acknowledgement (ACK) from a cognitive destination as to if it succeeds in decoding or not, called ACK and non-ACK based selective cooperation, respectively. We derive closed-form outage probability expressions for the two schemes with imperfect spectrum sensing, showing that an outage probability floor occurs in high signal-to-noise ratio (SNR) regions due to mutual interference between primary and secondary users. We consider the use of the outage probability floor to generalize the traditional diversity-multiplexing tradeoff (DMT) definition, based on which a DMT analysis is conducted for the non-ACK and ACK based selective cooperation schemes. We then extend the selective cooperation framework to a multiple-relay cognitive radio network considering the best cognitive relay only to participate in assisting secondary transmissions, referred to as the selective best-relay cooperation. We also consider the non-ACK and ACK based selective best-relay cooperation schemes and develop their DMTs by using the generalized DMT definition.
AB - In this paper, we first explore a selective cooperation framework for secondary user transmissions in a cognitive radio network with single relay. In the selective cooperation framework, two transmission modes (i.e., relay diversity transmission and non-relay direct transmission) are considered. We study two specific selective cooperation schemes with and without an acknowledgement (ACK) from a cognitive destination as to if it succeeds in decoding or not, called ACK and non-ACK based selective cooperation, respectively. We derive closed-form outage probability expressions for the two schemes with imperfect spectrum sensing, showing that an outage probability floor occurs in high signal-to-noise ratio (SNR) regions due to mutual interference between primary and secondary users. We consider the use of the outage probability floor to generalize the traditional diversity-multiplexing tradeoff (DMT) definition, based on which a DMT analysis is conducted for the non-ACK and ACK based selective cooperation schemes. We then extend the selective cooperation framework to a multiple-relay cognitive radio network considering the best cognitive relay only to participate in assisting secondary transmissions, referred to as the selective best-relay cooperation. We also consider the non-ACK and ACK based selective best-relay cooperation schemes and develop their DMTs by using the generalized DMT definition.
KW - Cooperative diversity
KW - cognitive radio
KW - diversity gain
KW - diversity-multiplexing tradeoff
KW - outage probability
KW - selective cooperation
UR - http://www.scopus.com/inward/record.url?scp=84866740077&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=84866740077&partnerID=8YFLogxK
U2 - 10.1109/TCOMM.2012.072612.110180
DO - 10.1109/TCOMM.2012.072612.110180
M3 - Article
AN - SCOPUS:84866740077
SN - 0090-6778
VL - 60
SP - 2467
EP - 2481
JO - IEEE Transactions on Communications
JF - IEEE Transactions on Communications
IS - 9
M1 - 6253205
ER -