Flexible Filter Bank Based on an Improved Weighted Overlap-Add Algorithm for Processing Wide Bandwidth Radio Astronomy Signals
Flexible Filter Bank Based on an Improved Weighted Overlap-Add Algorithm for Processing Wide Bandwidth Radio Astronomy Signals
复制标题
基于改进的加权重叠相加算法的灵活滤波器组处理宽带射电天文信号
DOI：
10.1086/684435
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发表时间：
2015-12
影响因子：
3.5
通讯作者：
Zhang Jianwei
中科院分区：
文献类型：
--
作者：
Wang Xianhai;Meng Qiao;Han J L;Liu Wei;Zhang Jianwei
来自射电望远镜的宽带信号必须为光谱观测或脉冲星观测的消色散而通道化。设计了一种基于改进的加权重叠相加(Iwola)算法的多相滤波器组来实现信道化。Iwola算法通过将每个子带的中心频率移位频段的一半来对常规WOLA滤波器组应用等价的Hilbert变换，从而Iwola滤波器组提供K个独立输出的复数子带而不是通常的K+1个子带，从而将后续处理单元减少一组。通过MATLAB仿真分析了Iwola滤波器组的性能。我们展示了如何将Iwola滤波器组用于两级高分辨率光谱仪，同时大大降低了片上块RAM的消耗。
Wideband signals from a radio telescope have to be channelized for spectral observations or for dedispersion for pulsar observations. A polyphase filter bank is designed based on the improved weighted overlap-add (IWOLA) algorithm to achieve channelization. The IWOLA algorithm involves applying an equivalent Hilbert transform to the normal WOLA filter bank by shifting the center frequency of every sub-band by a half of the frequency bin, so that the IWOLA filter bank provides K independently output complex subbands instead of the usual K + 1 sub-bands, reducing the subsequent processing units by one set. Performance of the proposed IWOLA filter bank is analyzed by means of MATLAB simulations. We show how the IWOLA filter bank can be used for a two-stage, high-resolution spectrometer, with a much reduced consumption of FPGA on-chip block RAM.