From special analogous crystal filters to digital impacting filters
- 作者：Man Feng ; seu_fengman@hotmail.com ; [Author Vitae] ; Lenan Wu ; [Author Vitae] ; Peng Gao ; [Author Vitae]
- 关键词：Crystal filter ; Digital impacting filter ; Ultra Narrow Band (UNB) ; Extended Binary Phase Shift Keying (EBPSK) ; Frequency response
- 刊名：Digital Signal Processing
- 出版年：2012
- 期刊代码：128_10512004
- 类别：cp
- 出版时间：July, 2012
- 卷：22
- 期：4
- 页码：690-696
- 文件大小：652 K
摘要
The implementation of high-speed and high-efficiency wireless communications, or Ultra Narrow Band (UNB) modulation, depends on the design of a special digital filter, which needs to not only maintain or even enlarge the minute differences in modulated waveforms, but also weaken noise or interference. This paper proposes a novel but simple digital impacting filter produced by exploiting the mechanism of zero group delay crystal filters. The proposed filter can cooperate with the usual small-angle modulation of UNB modulation, especially with Extended Binary Phase Shift Keying (EBPSK) modulation, which can convert the signal characteristics in noise into high-amplitude impacting at the phase jump points, such that the UNB signal is easy to detect. A computer simulation illustrates the validity of the proposed filter.