TY - JOUR
T1 - On the noise uncertainty for the energy detection of OFDM signals
AU - Chin, Wen Long
N1 - Funding Information:
Manuscript received July 22, 2018; revised January 21, 2019 and May 27, 2019; accepted May 28, 2019. Date of publication May 31, 2019; date of current version August 13, 2019. This work was supported in part by Grant MOST 107-2221-E-006-074, Taiwan. The review of this paper was coordinated by Prof. W. A. Hamouda.
Publisher Copyright:
© 2019 IEEE. Personal use is permitted, but republication/redistribution requires IEEE permission.
PY - 2019/8
Y1 - 2019/8
N2 - Orthogonal frequency-division multiplexing (OFDM) is a promising technology for communication systems. This paper investigates the impacts of unknown noise variance on the popular spectrum sensing scheme, i.e., energy detection, for OFDM cognitive radios over multipath fading channels. To study the effects of unknown parameters on the energy detector, a new maximum-likelihood estimation of noise and signal powers employing the cyclic prefix of OFDM is presented in this paper. The mean values and Cramér–Rao lower bounds of the estimation are obtained. Furthermore, the performances of the energy detector for both hypotheses, i.e., false-alarm rate and detection probability, under the influence of unknown noise variance are validated by both simulation and analytical results. The assessment on the required number of samples for the proposed energy detector is conducted, which indicates that an amount of 40–50% samples can be saved compared to the conventional energy detector.
AB - Orthogonal frequency-division multiplexing (OFDM) is a promising technology for communication systems. This paper investigates the impacts of unknown noise variance on the popular spectrum sensing scheme, i.e., energy detection, for OFDM cognitive radios over multipath fading channels. To study the effects of unknown parameters on the energy detector, a new maximum-likelihood estimation of noise and signal powers employing the cyclic prefix of OFDM is presented in this paper. The mean values and Cramér–Rao lower bounds of the estimation are obtained. Furthermore, the performances of the energy detector for both hypotheses, i.e., false-alarm rate and detection probability, under the influence of unknown noise variance are validated by both simulation and analytical results. The assessment on the required number of samples for the proposed energy detector is conducted, which indicates that an amount of 40–50% samples can be saved compared to the conventional energy detector.
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U2 - 10.1109/TVT.2019.2920142
DO - 10.1109/TVT.2019.2920142
M3 - Article
AN - SCOPUS:85090862447
SN - 0018-9545
VL - 68
SP - 7593
EP - 7602
JO - IEEE Transactions on Vehicular Technology
JF - IEEE Transactions on Vehicular Technology
IS - 8
M1 - 8727505
ER -