frequency mixing

Furthermore, we excogitate a IF signal processing platform based on software radio, and write procedures of frequency mixing, filtering, PPP ( Pulse Pair Processor) algorithm and FFT ( Fast Fourier Transform) algorithm via VC++.

接下来设计了基于软件无线电的中频信号处理部分，利用VC++编写混频、滤波、PPP（脉冲对处理）算法、FFT（快速傅立叶变换）算法的程序。

All the average methods for measuring ultrahigh frequency are based on the processing of frequency, the method for which is frequency mixing or harmonic mixing.

所有针对特高频率测量最基本的方法都是建立在对频率信号处理的基础上，而最常用的处理方法是混频或谐波混频的方法。

Using the time process, a higher precise can be reached, and ultrahigh resolution of perplexing frequency will be obtained. A detailed frequency mixing analyse process of two comparison signals is given.

系统利用时间处理方法实现时间和频率的高精度测量，可以进一步解决特高分辨率的复杂频率的测量。文章对两个比对信号的混频过程进行了详细的分析。

Based on heterodyne and vector analysis theories, origins and modes of the frequency mixing error and phase jump error were analyzed. On the above basis, procedures to improve the accuracy of the measurement system were suggested.

利用激光外差及矢量分析理论，深入研究了频率混叠误差和相位跳变误差的成因、变化规律，并讨论了提高测量系统精度的有效措施。

The tunable, coherent terahertz wave generation in a variety of isotropic semiconductor nonlinear crystals, such as ⅲ-ⅴ and ⅱ-ⅳ compounds, by difference frequency mixing is studied theoretically based on the theory of the cross-Reststrahlen band dispersion compensation phase-matching.

理论研究了利用剩余射线带色散补偿相位匹配原理，在Ⅲ-Ⅴ族和Ⅱ-Ⅳ族光学各向同性的半导体非线性晶体中差频产生可调谐THz波的可行性问题。