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arXiv · 0905.4684

A Simple Sequential Spectrum Sensing Scheme for Cognitive Radio

Abstract

Cognitive radio that supports a secondary and opportunistic access to licensed spectrum shows great potential to dramatically improve spectrum utilization. Spectrum sensing performed by secondary users to detect unoccupied spectrum bands, is a key enabling technique for cognitive radio. This paper proposes a truncated sequential spectrum sensing scheme, namely the sequential shifted chi-square test (SSCT). The SSCT has a simple test statistic and does not rely on any deterministic knowledge about primary signals. As figures of merit, the exact false-alarm probability is derived, and the miss-detection probability as well as the average sample number (ASN) are evaluated by using a numerical integration algorithm. Corroborating numerical examples show that, in comparison with fixed-sample size detection schemes such as energy detection, the SSCT delivers considerable reduction on the ASN while maintaining a comparable detection performance.

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BibTeXRIS

Yan Xin, Honghai Zhang. 2009-05-28. A Simple Sequential Spectrum Sensing Scheme for Cognitive Radio. https://arxiv.org/abs/0905.4684

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