VLSI design of OFDM baseband transceiver with dynamic spectrum access

The VLSI design of OFDM baseband transceiver is described, which is dedicated to cognitive radio systems. To facilitate dynamic spectrum accessing, this receiver architecture employs a specialized FFT module and a mapping/demapping module. Efficient mechanisms to omit input/output of unused subrcarriers are introduced. Also, calculation of spectrum intensity for subcarrier level carrier sensing is successfully integrated to the FFT module. Whole transmitter/receiver modules are implemented by maintaining compatibility with IEEE 802.11g. Implementation results show that the proposed architecture can process OFDM symbols in 60 MHz operation.