基于时域改进离散傅里叶变换调制滤波器组的多载频调制系统设计  

Design of multi-carrier transceivers based on time domain improved discrete Fourier transform

作　　者：计翔[1] 郭志刚[1] 王凯[1] 

机构地区：[1]移动通信技术重庆市重点实验室(重庆邮电大学),重庆400065

出　　处：《计算机应用》2014年第7期1978-1982,共5页journal of Computer Applications

基　　金：国家自然科学基金资助项目(61071195);科技部"中国-欧盟科技合作项目"(1018)

摘　　要：针对传统离散傅里叶变换(DFT)调制滤波器组设计时因原型滤波器时域反转条件带来的功率互补限制问题,从滤波器组时域完全重建条件角度提出一种时域改进方法设计DFT调制滤波器组,并将其应用于滤波器组多载频调制系统中。该时域改进设计方法放弃传统设计方法中原型滤波器的时域反转约束条件,即接收端滤波器组为发送端滤波器组的共轭转置形式,采用滤波器组时域完全重建条件矩阵方程设计接收端滤波器组,从而避免了对原型滤波器设计的功率互补条件限制,同时保证了滤波器组的完全重建特性。相比传统设计方法,该改进方法提高了滤波器组中原型滤波器的设计自由度,可以根据不同的应用场景选择适合的原型滤波器而无需考虑功率互补限制。基于该方法设计的多载频调制系统在正交相移键控(QPSK)调制、理想信道和3GPP TS 25.104人行多径信道以及单抽头频域均衡下有更好的误符号率(SER)性能。Concerning the power complementary limitation due to the time-reversed assumption of prototype filter in the design of traditional DFT （ Discrete Fourier Transform） modulated filter banks, a time domain modified method was introduced to design the DFT filter banks from the time domain perfect reconstruction perspectives in this paper. Moreover, the designed filter banks were applied to the filter banks based multi-carrier transceivers. The time domain modified method relaxed the time-reversed assumption of prototype filter, that is, the filter banks at the receiver were conjugate transpose form of the filter banks at the transmitter. Moreover, it adopted the time domain formula of the perfect reconstruction property as the solution to design the filter banks at the receiver, which would ensure the perfect reconstruction of filter banks and avoid the power complementary limitation in the design of prototype filter at the same time. Compared to the traditional design method, the time domain modified method improves the design freedom of prototype in the filter banks, so suitable prototype filters could be obtained according to the various application environments without considering power complementary restrictions. Moreover, the time domain modified DFF filter banks based multi-carrier transceivers has a better SER （ Symbol Error Ratio） performance in QPSK （ Quadrature Reference Phase Shift Keying） modulation, ideal and the 3GPP TS 25. 104 pedestrian multipath channel and one-tap frequency-domain equalization.

关 键 词：离散傅里叶变换 调制滤波器组 多载频调制系统 时域完全重建 原型滤波器 正交频分复用调制系统 

分 类 号：TN911.6[电子电信—通信与信息系统]