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Novel Spectrum Sensing Algorithms for OFDM Cognitive Radio Networks.

Shi Z, Wu Z, Yin Z, Cheng Q - Sensors (Basel) (2015)

Bottom Line: Simulation results illustrate that all of the three proposed methods can achieve good performance under low signal to noise ratio (SNR) with the presence of timing delay.Specifically, the DC-OFDM detector gets the best performance among the presented detectors.Moreover, both of the DC-CP and DC-PT detector achieve significant improvements compared with their corresponding original detectors.

View Article: PubMed Central - PubMed

Affiliation: School of Electronics and Information Engineering, Harbin Institute of Technology, 92 Xidazhi Street, Harbin150001, China. shizhenguotvt@gmail.com.

ABSTRACT
Spectrum sensing technology plays an increasingly important role in cognitive radio networks. Consequently, several spectrum sensing algorithms have been proposed in the literature. In this paper, we present a new spectrum sensing algorithm "Differential Characteristics-Based OFDM (DC-OFDM)" for detecting OFDM signal on account of differential characteristics. We put the primary value on channel gain θ around zero to detect the presence of primary user. Furthermore, utilizing the same method of differential operation, we improve two traditional OFDM sensing algorithms (cyclic prefix and pilot tones detecting algorithms), and propose a "Differential Characteristics-Based Cyclic Prefix (DC-CP)" detector and a "Differential Characteristics-Based Pilot Tones (DC-PT)" detector, respectively. DC-CP detector is based on auto-correlation vector to sense the spectrum, while the DC-PT detector takes the frequency-domain cross-correlation of PT as the test statistic to detect the primary user. Moreover, the distributions of the test statistics of the three proposed methods have been derived. Simulation results illustrate that all of the three proposed methods can achieve good performance under low signal to noise ratio (SNR) with the presence of timing delay. Specifically, the DC-OFDM detector gets the best performance among the presented detectors. Moreover, both of the DC-CP and DC-PT detector achieve significant improvements compared with their corresponding original detectors.

No MeSH data available.


ROC curves for different detectors with different noise at SNR = −10 dB.
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f10-sensors-15-13966: ROC curves for different detectors with different noise at SNR = −10 dB.

Mentions: The similar conclusions can be derived according to the ROC curves with different noise uncertainty shown in Figure 10 when SNR = −10 dB. It is apparent that the noise uncertainty could impact the Pd of all detectors. However, the decreasing of Pd is not huge when noise uncertainty is small, and all of the proposed detectors can achieve the good detection performance. For instance, when noise uncertainty is 1 dB, the DC-CP detector is markedly better than the CP detector with no noise uncertainty. Therefore, based on Figures 9 and 10 we can make the conclusion that although the proposed detectors do not have a very strong ability to resist noise uncertainty, they could still get the novel sensing performance when the accurate or relatively accurate noise power could be obtained.


Novel Spectrum Sensing Algorithms for OFDM Cognitive Radio Networks.

Shi Z, Wu Z, Yin Z, Cheng Q - Sensors (Basel) (2015)

ROC curves for different detectors with different noise at SNR = −10 dB.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC4507592&req=5

f10-sensors-15-13966: ROC curves for different detectors with different noise at SNR = −10 dB.
Mentions: The similar conclusions can be derived according to the ROC curves with different noise uncertainty shown in Figure 10 when SNR = −10 dB. It is apparent that the noise uncertainty could impact the Pd of all detectors. However, the decreasing of Pd is not huge when noise uncertainty is small, and all of the proposed detectors can achieve the good detection performance. For instance, when noise uncertainty is 1 dB, the DC-CP detector is markedly better than the CP detector with no noise uncertainty. Therefore, based on Figures 9 and 10 we can make the conclusion that although the proposed detectors do not have a very strong ability to resist noise uncertainty, they could still get the novel sensing performance when the accurate or relatively accurate noise power could be obtained.

Bottom Line: Simulation results illustrate that all of the three proposed methods can achieve good performance under low signal to noise ratio (SNR) with the presence of timing delay.Specifically, the DC-OFDM detector gets the best performance among the presented detectors.Moreover, both of the DC-CP and DC-PT detector achieve significant improvements compared with their corresponding original detectors.

View Article: PubMed Central - PubMed

Affiliation: School of Electronics and Information Engineering, Harbin Institute of Technology, 92 Xidazhi Street, Harbin150001, China. shizhenguotvt@gmail.com.

ABSTRACT
Spectrum sensing technology plays an increasingly important role in cognitive radio networks. Consequently, several spectrum sensing algorithms have been proposed in the literature. In this paper, we present a new spectrum sensing algorithm "Differential Characteristics-Based OFDM (DC-OFDM)" for detecting OFDM signal on account of differential characteristics. We put the primary value on channel gain θ around zero to detect the presence of primary user. Furthermore, utilizing the same method of differential operation, we improve two traditional OFDM sensing algorithms (cyclic prefix and pilot tones detecting algorithms), and propose a "Differential Characteristics-Based Cyclic Prefix (DC-CP)" detector and a "Differential Characteristics-Based Pilot Tones (DC-PT)" detector, respectively. DC-CP detector is based on auto-correlation vector to sense the spectrum, while the DC-PT detector takes the frequency-domain cross-correlation of PT as the test statistic to detect the primary user. Moreover, the distributions of the test statistics of the three proposed methods have been derived. Simulation results illustrate that all of the three proposed methods can achieve good performance under low signal to noise ratio (SNR) with the presence of timing delay. Specifically, the DC-OFDM detector gets the best performance among the presented detectors. Moreover, both of the DC-CP and DC-PT detector achieve significant improvements compared with their corresponding original detectors.

No MeSH data available.