In this thesis, we consider the efficient allocation of radio resource such as subcarriers and transmit power for Quality of Service (QoS: bit rate, bit error rate) support in cellular OFDMA systems with an adap-tive modulation. The major impairment considered is the Co-Channel Interference (CCI). We considered two key objectives of the resource allocation, which are the minimization of co-channel interference effect and provision of the required QoS.
In order to efficiently handle the co-channel interference, we considered two different frequency reuse schemes, fixed and variable. On the other hand, Dynamic Channel Assignment (DCA) scheme with adaptive modulation is applied to support the required bit rate and BER of the users, while minimizing the total transmit power. By the application of the DCA approach, the radio resources can be used more efficiently.
Simulation results show that when the system load is higher, the variable frequency reuse system performs better than the fixed frequency reuse system.