Micro-slotted Dual-stage Spectrum Sensing for Cognitive radio networks

Abstract

Spectrum sensing is used to determine an existence of a primary user in order to avoid harmful interference to the primary user caused by a secondary user in cognitive radio network. In general sensing, a PU is assumed to use the band since the beginning of the sensing period. In fact, a PU can be active at any time of the sensing period.
 In this paper, we propose a novel technique — micro-slotted dual-stage spectrum sensing (MDMS) — to detect a PU no matter when it is active during the sensing period. The technique also addresses low SNR due to path loss effect in an adaptive fashion. The technique is more reliable compared to previous works of MDCAED and DCAED. MDMS is shown that it meets the spectrum sensing requirement (IEEE 802.22) of sensing time for all distances and gives the best detection performance among the other techniques. Not only the primary user can be ensured that its transmission will not be interfered by the secondary user, the number of detecting spectrum bands by the SU also increases because it consumes short sensing time. Thus, the efficiency of spectrum utilization can be improved.