Optimal multiband joint detection in cognitive radio networks with the Taguchi method

Abstract

SUMMARYThis paper studies multiband joint detection in cognitive radio networks with the Taguchi method. At the fusion center, linear fusion rule is adopted to collect the observations from distributed secondary users. We aim to achieve maximum aggregate throughput with limited aggregate interference. The problem is challenging due to its nonconvexity and high computational complexity to find the global optimum. Existing works attempt to convert the problem into convex optimization problem. In this paper, the Taguchi method is employed to estimate the gradient of the aggregate throughput, determine the optimal thresholds of the energy detectors and combination weights of the linear fusion rule regardless of convexity. To optimize thresholds and linear weights simultaneously, we employ newly defined variables to represent the changing ranges of detector thresholds when we search for optimal linear weights. In addition, the sensing duration is another factor to be optimized in the Taguchi method. The simulation results show that the proposed method is efficient and applicable for all classes of cognitive radio without considering convexity. The optimization performance is considerably improved. Moreover, the Taguchi method is insensitive to parameter initialization, which provides a relatively robust output. Copyright © 2013 John Wiley & Sons, Ltd.

Performance evaluation of energy based spectrum sensing in multipath fading channel for cognitive radio system

“…channel since it is independent xpressed as exp u du (8) density function (pdf) [5] of the to evaluate the probability of…”

“…T 978-1-4799-6646-2/14/$31.00 ©2014 IEEE As reported in [8] the Local Spectrum Sensing (LSS) such as energy detector may not afford adequate precision due to the impulses of the wireless medium such as fading and shadowing [8]. Atapattu [9] studied data / decision fusion strategies for Rayleigh fading channels and derived new set of average detection probability.…”

Reducing the effects of the noise uncertainty in energy detectors for cognitive radio networks

“…The work presented in Du and Zhang [14], dynamically adjusts the detection threshold to the queue occupancy necessary to comply with a desired statistical quality of service of the SU, provided that the interference to the PU is limited to an acceptable level. The joint optimization of detection thresholds and sensing time for multiband joint detection is derived in Ma and Liu [15], where the optimal detection threshold and sensing time for each individual frequency band are obtained for maximizing the throughput of the secondary system with the aim of sensing a wideband channel while the throughput of the secondary system is maximized.…”

Polyphase filter bank based multi‐band spectrum sensing in cognitive radio systems

“…Theoretical detection thresholds are therefore computed, which ensures a fair comparison for different detectors. An optimal multiband joint detection in CR networks using Taguchi method was proposed in [41]. However, the literature of multi-band sensing that monitors multiple frequency bands simultaneously is very limited.…”

“…These two sensing stages collaborate with each other to enhance the accuracy of spectrum sensing performance. An optimal multiband joint detection in CR networks using Taguchi method was proposed in [41]. In [37], a novel approach called segmented periodogram for wideband spectrum segmentation was proposed.…”