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Spectrum bands are the backbone of wireless networks. Every user is allocated a fraction of the spectrum from available fixed spectrum band. But, the fixed available spectrum band cannot accommodate the growing demands of wireless networks. To accommodate the growing demand of wireless networks, the different multiple access schemes and Cognitive Radio (CR) networks come to fulfill these demands. Multiple access schemes are nothing but the schemes that can multiplex the numbers of users then transmit over the medium, whereas CR networks allow using unutilized frequency bands of spectrum through dynamic or opportunistic way. Till now, OFDMA is well known and most successful multiplexing scheme among other schemes for advanced wireless networks. It can accommodate large number of users with higher data rates than others. Due to the popularity of smart devices having video and other …