Spectrum sharing in Cognitive Radio Networks

Las redes de radio cognitivas son el siguiente paso para abordar la escasez de redes inalámbricas dado el aumento demanda de espectro radioeléctrico donde la solución propuesta es compartir dicho recurso para mejorar este situación. En el presente artículo, una revisión del estado actual del espectro compartido en las redes de radio cognitivas. Para lograr este propósito, se revisaron los artículos publicados en los últimos 4 años sobre la materia incluyendo temas como redes móviles y televisión. Algunos estudios y simulaciones propuestos para compartir el espectro son mostrados. El estado actual de los estudios revela que se han producido importantes avances en esta área de investigación sin embargo, es necesario continuar estudios similares y poner en marcha diferentes esquemas.Cognitive radio networks are the next step to tackle scarcity in wireless networks given the increasing demand of radioelectric spectrum where the proposed solution is to share said resource to improve this situation. In the present article, a review of the current state of spectrum sharing in cognitive radio networks. To achieve this purpose, the articles published over the last 4 years on the matter were reviewed including topics such as mobile networks and TV. Some studies and simulations proposed to share the spectrum are shown. The current state of the studies reveals that there has been significant progress in this research area yet it is necessary to continue similar studies and set in motion different schemes

Cognitive Radio Relay Network Performance Analysis by using Game Theory

Cognitive radio plays a vital role in wireless communication system. The cognitive radio consists of a transceiver which is used to check the availability of channel for communication and avoids busy channels by shifting into a unused channel. The scope for spectrum availability and area of coverage is increased by using cognitive radio. In cooperative cognitive relay network the primary traffic the primary users (PUs) will nominate some of the secondary users (SUs) as a relay. To make the secondary users co-operate with the primary user, primary user have to allocate some channel to the secondary user for data transmission. This significantly reduces the performance of the primary users and secondary users. Therefore, performance can be significantly increased by using MIMO in co-operative cognitive radio. By using beam forming technique in spatial domain over the multiple inputs multiple output antenna permits multiple data streams and suppression of interference. Using Nash Equilibrium (NE) to control the power among SUs, the PUs utilities and SUs utilities are obtained in MIMO-CCRN. By using MIMO technique the secondary users can co-operatively relay the data for the primary users while concurrently accessing the same channel to transmit its data. Time domain and spatial domains are examined to improve the efficiency of the spectrum for arranging the MIMO co-operative cognitive radio networks. DOI: 10.17762/ijritcc2321-8169.16043