Alias-Free Digital Click Modulator
Alias-Free Digital Click Modulator
复制标题
无混叠数字点击调制器
DOI：
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复制
发表时间：
2013
影响因子：
12.3
通讯作者：
E. Paolini
中科院分区：
文献类型：
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作者：
L. Stefanazzi;A. Oliva;E. Paolini
本文设计了一种无混叠的离散时间咔嗒声调制器。以前的方法依赖于翻译的连续时间点击调制器的离散时间设置，虽然在点击调制器的一个关键组成部分-解析指数调制器-不能完全转换到离散域。文献中报道的每一个离散时间版本的点击调制器都容易产生混叠效应，使用插值技术可以改善混叠效应，但不能消除混叠效应。输出方波的开关时间精度对于点击调制至关重要，因为其确定的不确定性会对调制器的性能和SNR产生不利影响。提出了一种利用频域信息计算开关时间的新方法。这两种技术被用来开发一个离线的离散时间点击调制器，实现信噪比大于180分贝的多音调和带通信号。
An alias-free, discrete-time click modulator is developed in this paper. Previous approaches rely on translating the continuous-time click modulator to a discrete-time setting, although a key component in the click modulator - the analytic exponential modulator-cannot be exactly transformed to the discrete domain. Every discrete-time version of the click modulator reported in the literature is prone to aliasing effects that are ameliorated, but not eliminated, using interpolation techniques. The precision of the switching times of the output square wave is critical to click modulation because uncertainties in their determination adversely affect the performance and SNR of the modulator. A novel method that uses frequency domain information to compute these switching times without error is also presented. This two techniques are used to develop an off-line discrete-time click modulator that achieves a SNR larger than 180 dB for both multitonal and bandpass signals.