1) frequency fold-back mode(FFM)
频率回扫模式
2) multifrequency modes
多频率模式
1.
In such a LiNbO3 superlattice with aperiodic structure,terahertz waveforms with multifrequency modes were simulated,based on the second-order nonlinear optical rectification effect of femtosecond pulse.
在此非周期结构的LiNbO3超晶格中,基于飞秒脉冲二阶非线性光学整流效应,模拟多频率模式的太赫兹波形。
3) Frequency sweep
频率扫描
1.
The direct digital synthesizing frequency sweep signal system based on the technique of ISP;
基于ISP技术的数字频率扫描信号发生系统
2.
In the linear viscoelastic region, the frequency sweep measurement results showed that the waste liquor polymer solution has viscoelasticity.
在线性粘弹性范围内,频率扫描试验得出:甘蔗渣浆废液多聚物是具有一定粘弹性的粘弹体,增加固含量和提高温度都会提高复合模量G*,粘弹性更突出。
3.
A novel method of direct digital synthesizing frequency sweep signal is presented.
介绍了利用直接数字合成技术产生频率扫描信号的新方法。
4) frequency scanning
频率扫描
1.
The frequency scanning method is used to analyze the series-capacitor compensation of Baise in different compensation degrees,and the result show.
并用频率扫描法分别分析了百色串补线路在不同串补度下的谐振问题,说明了长距离输电系统在高串补度下容易引起次同步谐振。
2.
An approach of frequency scanning is used to research .
从薄板自由振动的微分方程式出发,采用动态基本解推导出其相应的边界积分方程式,计算中对边界积分方程进行缩减,应用频率扫描的方法研究薄板的动态特性,准确、有效地得到了其相应的固有频率。
3.
Compare with other electronic scanning antennas, the frequency scanning antenna is lower cost and complexity, and easy to form a large array.
频率扫描天线阵就是电扫描天线的一种,当改变其工作频率时,阵列各单元的相位关系就跟着变化,波瓣指向随之改变。
5) sweep frequency
扫描频率
1.
After simply analyzing the deficiencies in countermeasures to the concealing scanning radar angular following system,a new method is presented which means scanning slowly in a smaller range after quickly scanning to get the precise sweep frequency.
分析了对隐蔽扫描雷达角跟踪系统实施匀速扫频式干扰的缺点,提出了一种实现快速-慢速扫频的方法,即先快速扫描以捕捉雷达角扫描频率范围,再在此小范围内进行慢扫,以确定敌方雷达的角扫描频率。
补充资料：动态频率扫描
动态频率扫描
超声学检查技术之一。通过多频探头和可变带通滤波器的结合，不用更换探头，就能自动转换工作频率，在近场使用高频率，在远场使用低频率的技术。具有高分辨力和高灵敏度这两个互相排斥的特点，可把各个单频探头的图像质量最佳之处取出并组合一体。采用超低杂波、宽带放大器及超声波发射、接收效率均佳的多层探头，从而做到分辨力高，穿透性强，图像清晰，杂波少。
说明：补充资料仅用于学习参考，请勿用于其它任何用途。
参考词条