Practical Spectrum Aggregation for Secondary Networks With Imperfect Sensing

TY - JOUR

T1 - Practical Spectrum Aggregation for Secondary Networks With Imperfect Sensing

AU - Lee, Haeyoung

AU - Ko, Youngwook

AU - Vahid, Seiamak

AU - Moessner, Klaus

PY - 2016/7/1

Y1 - 2016/7/1

N2 - We investigate a collision-sensitive secondary network that intends to opportunistically aggregate and utilize spectrum of a primary network to achieve higher data rates. In opportunistic spectrum access with imperfect sensing of idle primary spectrum, secondary transmission can collide with primary transmission. When the secondary network aggregates more channels in the presence of the imperfect sensing, collisions could occur more often, limiting the performance obtained by spectrum aggregation. In this context, we aim to address the following fundamental query: How much spectrum aggregation is worthy with imperfect sensing? For collision occurrence, we focus on two different types of collision: One is imposed by asynchronous transmission, and the other is imposed by imperfect spectrum sensing. The collision probability expression has been derived in closed form with various secondary network parameters: primary traffic load, secondary user transmission parameters, spectrum sensing errors, and number of aggregated subchannels. In addition, the impact of spectrum aggregation on data rate is analyzed under the constraint of collision probability. Then, we solve an optimal spectrum aggregation problem and propose the dynamic spectrum aggregation approach to increase the data rate subject to practical collision constraints. Our simulation results clearly show that the proposed approach outperforms the benchmark that passively aggregates subchannels with lack of collision awareness.

AB - We investigate a collision-sensitive secondary network that intends to opportunistically aggregate and utilize spectrum of a primary network to achieve higher data rates. In opportunistic spectrum access with imperfect sensing of idle primary spectrum, secondary transmission can collide with primary transmission. When the secondary network aggregates more channels in the presence of the imperfect sensing, collisions could occur more often, limiting the performance obtained by spectrum aggregation. In this context, we aim to address the following fundamental query: How much spectrum aggregation is worthy with imperfect sensing? For collision occurrence, we focus on two different types of collision: One is imposed by asynchronous transmission, and the other is imposed by imperfect spectrum sensing. The collision probability expression has been derived in closed form with various secondary network parameters: primary traffic load, secondary user transmission parameters, spectrum sensing errors, and number of aggregated subchannels. In addition, the impact of spectrum aggregation on data rate is analyzed under the constraint of collision probability. Then, we solve an optimal spectrum aggregation problem and propose the dynamic spectrum aggregation approach to increase the data rate subject to practical collision constraints. Our simulation results clearly show that the proposed approach outperforms the benchmark that passively aggregates subchannels with lack of collision awareness.

KW - Collision probability

KW - opportunistic spectrum access

KW - secondary networks

KW - spectrum aggregation

UR - http://www.scopus.com/inward/record.url?scp=84979205128&partnerID=8YFLogxK

U2 - 10.1109/TVT.2015.2465388

DO - 10.1109/TVT.2015.2465388

M3 - Article

AN - SCOPUS:84979205128

SN - 0018-9545

VL - 65

SP - 5474

EP - 5484

JO - IEEE Transactions on Vehicular Technology

JF - IEEE Transactions on Vehicular Technology

IS - 7

M1 - 7181718

ER -