Three digital interpolation designs, conventional time domain interpolation, circular time domain interpolation and frequency domain interpolation, for use in orthogonal frequency division multiplex (OFDM) transmitters are presented. They are compared in terms of the amount of inter-symbol interference (ISI) they produce and their
computational complexity. The results show that both the circular time domain and frequency domain interpolation designs produce the lowest ISI while the circular time domain interpolation design is the most computationally efficient technique.