A Subcarriers Coding Technique for MB-OFDM Cognitive Radio

For the problem of intercarrier interference in orthogonal frequency division multiplexing (OFDM) signals of cognitive radio systems,a coding method for enhancing spectrum notch of OFDM signals is proposed.The same dates are transmitted on the two adjacent subcarriers,and then weight the dates on the two adjacent subcarriers to make their sidelobes cancel each other out at the frequency of spectrum notch,so as to reduce the power spectrum at specific frequency.Theoretic analysis and simulation results show that,not only the method can enhance the spectrum notch but also has a good performance of anti-noise.