软件无线电中的多频段信号带通采样

Bandpass sampling of multiband signals in software defined radio

针对软件无线电(SDR)技术中的多频段信号带通均匀采样技术,提出了一种能够高效、准确地求解最小采样频率的方法。该方法从理论上可能的最小采样频率出发,根据采样后频谱不发生混叠的3种约束条件来确定可变的频率步长,搜索可用的最小频率。在求解过程中同时考虑到采样后频谱之间的保护带宽。具体的工程算例表明采用该方法能够快速准确地计算出最小采样频率。与其他方法相比,该方法计算复杂度较低,能够避免频谱倒置的情况,并且可以兼顾频谱间的保护间隔。

An efficient method is presented to find the minimum valid sampling frequency for bandpass sampling of multiband signals in software defined radio （SDR） technology. The method starts with the theoretically minimum frequency and searches for the minimum valid sampling frequency using variable step sizes subject to three non-aliasing constraints. The guard-bands between the downconverted signal spectra are analyzed to determine the minimum sampling frequency. An example illustrates that the minimum valid frequency is rapidly and accurately determined. This method is less computationally complex than other similar approaches, and avoids spectrum inversions, while intruding analyses of the guard-bands.