Application of weighted fractional Fourier transform in hybrid system

为提高通信系统在复杂水声环境下的鲁棒性,提出基于加权分数傅里叶变换WFRFT(weighted fractional Fourier transform)的混合载波系统.对混合系统进行优化设计,以最低误比特率为优化目标,求解得到系统的最优变换阶次,得到优化的系统性能.仿真和水池实验表明,基于WFRFT的混合载波系统在多径信道下的误比特率介于传统的单/多载波系统之间;而在双选信道下,其最优阶的系统性能优于单/多载波系统.该混合系统具有单/多载波的优良性能,在提高通信系统鲁棒性方面,具有很大的应用前景.To improve the robustness of the communication system in complex underwater acoustic environment,the hybrid carrier system based on WFRFT was put forward. To obtain the optimal transformation order,the hybrid carrier system is designed with the lowest bit error rate as optimization goal. Simulation results show that BER performance of hybrid carrier system is between the traditional single / multi carrier systems in multipath channels.However,system performances with the optimal order are superior to single / multi carrier systems under the doubly selective fading channels. It has the excellent characteristics of the single / multi carrier systems and it is thus prospective in improving the robustness of the communication system.国家自然科学基金(61471309);; 福建省自然科学基金(2013J01258