Electrical - Electronic Engineering / Elektrik - Elektronik Mühendisliği

Permanent URI for this collectionhttps://hdl.handle.net/11147/11

Browse

Filters

2019 - 20202

Settings

Subject: search.filters.subject.Alpha-stable noiseWoS Q: search.filters.wosQuartile.Q4

Search Results

Now showing 1 - 2 of 2
  • Article
    Citation - WoS: 6
    Citation - Scopus: 6
    Structure and Performance Evaluation of Fractional Lower-Order Covariance Method in Alpha-Stable Noise Environments
    (Bentham Science Publishers B.V., 2019) Ahmed, Areeb; Savacı, Ferit Acar
    Background: All existing time delay estimation methods, i.e. correlation and covariance, depend on second or higher-order statistics which are inapplicable for the correlation of alpha-stable noise signals. Therefore, fractional lower order covariance is the most appropriate method to measure the similarity between the alpha-stable noise signals. Methods: In this paper, the effects of skewness and impulsiveness parameters of alpha-stable distributed noise on fractional lower order covariance method have been analyzed. Results: It has been found that auto-correlation, i.e. auto fractional lower order covariance, \ of non delayed alpha-stable noise signals follows a specific trend for specific ranges of impulsiveness and skewness parameters of alpha-stable distributed noise. The results also depict that, by maintaining the skewness and impulsiveness parameters of alpha-stable noise signals in a certain suggested range, better auto-correlation can be obtained between the transmitted and the received alpha-stable noise signals in the absence and presence of additive white Gaussian noise. Conclusion: The obtained results would improve signal processing in alpha-stable noise environment which is used extensively to model impulsive noise in many noise-based systems. Mainly, it would optimize the performance of random noise-based covert communication, i.e. random communication.
  • Article
    Citation - WoS: 5
    Citation - Scopus: 8
    Covert Electromagnetic Nanoscale Communication System in the Terahertz Channel
    (World Scientific Publishing, 2020) Ahmed, Areeb; Savacı, Ferit Acar
    In this paper, an electromagnetic nano random communication system (EM-nRCS) has been proposed which ensures covert communication in the terahertz (THz) band. In the proposed system, the skewed alpha-stable noise shift keying method has been used to transmit random noise signals (RNSs) from the nano-transmitter (NT) by utilizing single-walled/carbon nanotubes-based true random number generator (SWCNTs-TRNG) and a graphene-based nano-antenna. A line-of-sight THz transparency window between 0.1 THz and 0.5 THz in the THz channel with spreading loss, molecular absorption loss and molecular absorption noise has been considered. Due to the broadband nature of the RNSs, the proposed EM-nRCS provides efficient transmission by overcoming the high path loss and intense channel noise arising from random fluctuations in the THz band. Non-coherent nano-receiver (NR) consisting of the modified extreme value method (MEVM) estimator has been proposed to extract the hidden binary information in the received RNSs. The bit error rate performance shows that the proposed EM-nRCS ensures high performance and covertness for future EM nanoscale communication devices.