They measured the radiofrequency instead of optical frequency measurement with optical frequency comb and technology of octave-spanning.
利用光频梳和倍频技术，把对光频的测量变为对射频的测量，这样就能够很容易地测出光的频率。
2
Electromagnetic compatibility (EMC) - Part 4-3: Testing and measurement techniques - Radiated, radio-frequency, electromagnetic field immunity test.
电磁兼容性(emc)。第4 - 3部分：试验和测量技术。辐射、射频和电磁场抗干扰试验。
3
The vector network analyzer is the special instrument that tests microwave and radiofrequency devices, its application is very extensive in the wireless measurement field.