276 Abstract—In this paper we consider a mobile cellular network where two types of users: primary user (PU) and cognitive user (CU) share the entire spectrum of the base station (BS). Opportunistic scheduling scheme of CU is widely used to alleviate interference between CU and PU users. Recent literature deals with such networks under Rayleigh fading environment. The objective of this paper is to determine the performance of such networks under Nakagami-m fading environment and to compare the results with the results for the Rayleigh fading model. The paper shows the comparison of average bit error rate (BER) and mean channel capacity of target transmission rate taking outage probability as a parameter. It is found that for comparatively lower value of the outage probability the Nakagami-m fading has higher BER than the corresponding Rayleigh fading case whereas for higher values of the outage probability the situation becomes reverse. It is further observed that the channel capacity under Nakagami-m fading environment is better than the Rayleigh fading environment. The paper depicts the real-time performance with some explanations.