Implementation of OFDM baseband transceiver with dynamic spectrum access for cognitive radio systems
Ryoji Hashimoto, Toshimitsu Tatsuka, Masahide Hatanaka, Takao Onoye, Hironobu Hatamoto, Shinsuke Ibi, Sinichi Miyamoto, Seiichi Sampei · 2009
VLSI architecture for OFDM baseband transceiver is developed, which is dedicated to cognitive radio systems. To facilitate dynamic spectrum access, this transceiver architecture employs a specialized FFT/IFFT module and a mapping/demapping module. Efficient mechanisms to omit input/ output of unused subcarriers 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 keeping compatibility with IEEE 802.11g. A prototype system is constructed by using Xilinx Virtex-II FPGA, which can transmit video sequence in real time.