Relay assisted spectrum sensing in presence of in-phase and quadrature-phase imbalance in multi-channel system

The increasing demand for wireless technology leads to dynamic spectrum access, which is positively accomplished by cognitive radio (CR) technology. For its acceptable efficiency, it needs a robust detection scheme that detects the spectrum holes. This paper investigates a cooperative spectrum sensing method for a relay-based cognitive radio network. In general, a relay is a low-cost device. It is more prone to hardware impairment such as In-phase and Quadrature-phase Imbalance (IQI), which can considerably limit the capabilities of sensing spectrum holes. This work studies the energy detection (ED) based spectrum sensing in multi-channel receiver scenarios affected by IQI. The detection and false alarm probabilities considering Gaussian primary user signal models are derived. Our results are simulation-based and verified with theoretical findings.