Hybrid carrier order selection scheme based on minimum mean square error equalization

In this letter, the relationship between the transformation order and the interference power in the hybrid carrier (HC) system is analyzed. The transformation order does not affect the total interference power but influences the distribution of the interference power. Furthermore, the more uniform the interference power distribution is, the better performance HC system can achieve. Then, an optimal order selection scheme is proposed by minimizing the interference power variance. Simulation results show that the proposed scheme can provide significant performance improvement compared with the fixed order HC system and the minimizing carrier-to-interference ratio order selection HC system under doubly selective channels.