Adaptive SC-FDMA with pulse shaping for wireless cognitive radio

This paper investigates SC-FDMA method for dynamic spectrum access and cognitive radios. SC-FDMA can be viewed as a modified OFDMA with low peak power characteristics. In addition, SC-FDMA provides high frequency diversity compared to OFDMA, and allows flexible spectrum sharing between different users. We show that, this method has better performance than OFDMA, in power consumption and Bit Error Rate in frequency selective fading environments. We also compare the out-of band radiation of SC-FDMA with OFDMA, and consider that SC-FDMA similar to OFDMA suffers from high out-of-band radiation. We propose using of pulse shaping for decreasing the out-of-band radiation. A significant reduction of out-of band radiation is achieved by this technique at the cost of a small degradation in system performance.