近似精确重构的低复杂度星载信道化器  

Nearly perfect reconstruction onboard channelizer of low complexity

作　　者：田斌[1,2] 李晨曦 TIAN Bin;LI Chenxi(State Key Laboratory of Integrated Services Networks, Xidian University, Xi’an 710071, China;Collaborative Innovation Center of Information Sensing and Understanding, Xidian University, Xi’an 710071, China)

机构地区：[1]西安电子科技大学综合业务网理论及关键技术国家重点实验室,陕西西安710071 [2]西安电子科技大学信息感知技术协同创新中心,陕西西安710071

出　　处：《系统工程与电子技术》2019年第6期1395-1401,共7页Systems Engineering and Electronics

基　　金：中国电子科技集团公司航天信息应用技术技术重点实验室开放基金(XX17629X009)资助课题

摘　　要：提出频率响应遮蔽(frequency response masking,FRM)与改进型离散傅里叶变换(modified discrete Fourier transform,MDFT)相结合的近似精确重构的低复杂度星载信道化器。其中,FRM结构可以较低复杂度设计出过渡带陡峭的有限冲激响应滤波器(finite impulse response,FIR)低通原型,MDFT滤波器组结构可以基本消除滤波器组的邻带混叠,将FRM结构中不适合邻带拼接的结构改进为高通、低通滤波器互补结构,降低了拼接抖动。调整MDFT结构中的上采样率,使之适合于奇偶分离的信道化器。继而提出新的结构,更适合应用于非均匀带宽。仿真表明,所提方法具有更低的运算复杂度,更陡峭的过渡带和更窄的保护间隔,更小的重构误差。This paper proposes a nearly perfect reconstruction onboard channelizer of low complexity combining frequency response masking (FRM) with modified discrete fourier transform (MDFT). Of the two techniques,the FRM structure can design a low-pass finite impulse response (FIR) prototype filter with a steep transition band with low complexity, while the MDFT filter bank structure can mostly eliminate the adjacent band aliasing . Replacing the structure of the FRM that is not suitable for the adjacent band splicing by a high-pass and low-pass filter complementary structure,the splice jitter can be reduced. The upsampling rate in the MDFT structure is adjusted to make it suitable for the odd-even split channelizers. Then a new structure is put forward, which is more suitable for non-uniform bandwidth applications. Simulations show that this method has a lower computational complexity, a steeper transition band and narrower guard interval, and a smaller reconstruction error.

关 键 词：频率响应遮蔽 改进型离散傅里叶变换 重构误差 滤波器组 信道化器 

分 类 号：TN927[电子电信—通信与信息系统]