Selection of the Number of Used Subcarriers for OFDM Systems in Interference-limited Environments

One way to mitigate interference in Orthogonal Frequency Division Multiplexing systems is to use a reduced number of subcarriers instead of full resources. Assuming there is no information on the positions of used subcarriers of interferers, this paper discusses the optimal number of used subcarriers to maximize the system performance. If the noise level is negligible compared to the interference amount, the number of used subcarriers needs to be decreased inversely proportional to the number of users.