Now showing items 1-2 of 2

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    Adaptive Two-stage Spectrum Sensing under Noise Uncertainty in Cognitive Radio Networks 

    Kornkamol Thakulsukannant; Wilaiporn Lee; Akara Prayote; Kanabadee Srisomboon (2016)

    To utilize licensed spectrum bands efficiently, spectrum sensing needs to be accurate and fast. The occurrence of noise uncertainty and the lower in received PU signal power due to the distance between the transmitter and the receiver, path loss, are the main challenges that has a great impact on the accuracy of spectrum sensing. In this paper, we propose a new scheme of two-stage spectrum sensing, “Adaptive Two-stage Spectrum Sensing (ATSS)”, under noise uncertainty environment. ATSS is a modified of a conventional two-stage spectrum sensing ...
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    The Switching Bilateral Denoising Performance Influence of Spatial and Radiometric Variance 

    Kriengkri Langampol; Wilaiporn Lee; Vorapoj Patanavijit (2016-06)

    In this paper, we investigate the performance of switching bilateral filter (SBF) influenced by two parameters — radiometric variance ( R σ ) and spatial variance ( S σ ). The SBF can be used to filter Gaussian noise and impulse noise at the same time. For SBF, R σ and S σ are the two most important factors that affect increasing /decreasing the performance of SBF. Then, we investigate the influence of two parameters by varying their values from 1 to 100 and evaluate the performance of the de-noising for seven types of image under ...