In this paper we study the capacity of the OFDMA-based IEEE802.16 WiMAX network in the presence of two types of traffic, streaming (Real-Time) and elastic (Non-Real-Time) including Adaptive Modulation and Coding (AMC). Many studies in the literature assumed that packets or calls arrive to the system according to poisson process for the sake of analytical simplicity. However, it has been recently proved that the exponential distribution is inappropriate [2]. Based on the generalized traffic processes developed [2], we study the media access control (MAC) layer of WiMAX and develop a resource allocation that maintain the bit rate of real time connections independently of the user position in the cell. Using Markovian analysis we evaluate the impact of our resource allocation on the non-real time connection (NRT) as expected delay and throughput.