COGNITIVE RADIO: CONCEPTS, SPECTRUM SENSING AND ITS STANDARDS
Shewangi · International Journal of Advanced Research in Computer Science · 2017
Cognitive radio is consider to be outlook of wireless communication system as it is responsible for many operations like using spectrum opportunistically, sensing the environment and its internal state. In this paper a brief overview of SDR or reconfigurable radio is discussed. Spectrum sensing is used to adapt, learn and aware of the environment. This problem is one of the most challenging issues in cognitive radio system. In this paper different sensing issues is presented. There are many standards that are used in wireless communications. Wireless technologies that need some sort of spectrum sensing for variation or for dynamic frequency access (DFA) are discussed.SDR is used to change the operation of the terminals. The cognitive radio is centrally a SDR which already knows the environment, state, position and therefore adjusts its operations according to the desired objectives. Recently many wireless standards started adopting cognitive features all of them are discussed in detail.