A new flexible channel access scheme using overlap FFT filter-bank for dynamic spectrum access

An OFDMA based channel access scheme is proposed for dynamic spectrum access to utilize frequency spectrum efficiently. However, the OFDMA signal has large PAPR (Peak to Average Power Ratio). In addition, if the OFDMA receiver does not use filter(s) to extract block(s) of sub-carriers before FFT (Fast Fourier Transform), the designated sub-carriers suffer large ACI (Adjacent Channel Interference) in the FFT processing. To solve these problems of PAPR and ACI, this paper proposes a new flexible channel access scheme using overlap FFT filter-bank based on single carrier modulation for dynamic spectrum access. It also evaluates the performance by computer simulation.