cover

Experimental and Theoretical NANOTECHNOLOGY

About the Journal :

Experimental and Theoretical NANOTECHNOLOGY (ETN) is a multidisciplinary peer-reviewed international journal published four issues a year. It includes specialized research papers, short communications, reviews and selected conference papers in special issues on the characterization, synthesis, processing, structure and properties of different principles and applications of NANOTECHNOLOGY; with focus on advantageous achievements and applications for the specialists in engineering, chemistry, physics and materials science.

ETN covers and publishes all aspects of fundamental and applied researches of experimental and theoretical nanoscale technology dealing with materials synthesis, processing, nanofabrication, nanoprobes, spectroscopy, properties, biological systems, nanostructures, nanoelectronics, nano-optics, nano-mechanics, nanodevices, nanobiotechnology, nanomedicine, nanotoxicology within the scope of the journal. ETN aims to acquire the recent and outstanding researches for the benefit of the human being.



OVERVIEW OF SPECTRUM SENSING TECHNOLOGIES FOR SATELLITE AND SPACE COMMUNICATIONS BASED ON COGNITIVE RADIO NETWORKS

The limited available spectrum of satellite and space communications result in new techniques to reuse the free spectrum. Cognitive Radio (CR) is one of the most promising techniques for such reusing processes. Spectrum sensing (SS) is the core process of cognitive radio which is used to sense the available temporary free bands, holes, of the sensed spectrum. Many technologies are proposed to achieve both narrow-band and wide-band spectrum sensing. Three paradigms of spectrum sensing applications such as the interweaving approach, the underlay approach and the overlay approach are explained. Many scenarios are proposed to utilize cognitive radio architecture at both standalone and cooperative approaches in satellite communications . The proposed scenario is based on cooperative Sub-Nyquist wideband sensing basis. Nanocomputing process is highly required to achieve real-time communication for spectrum sensing in cognitive radio due to the intensive required computations. The Simulation of the proposed scenario showed that it efficiently saves frequency resources, overcomes spectrum underutilization problem, noise and interference problems with an accurate reconstruction.

Keywords:

PACS: Cognitive Radio; Spectrum Sensing; Space Communication; Wideband Sensing; Compressive sensing; Sub-Nyquist Sampling; cooperative satellite communication