To minimize the frequency and phasedistortion in a DTV transmitter in order to achieve best VSB frequency performance, a pre equalizer can be inserted into the modulator.
In high power laser system, a small size phase-distortion wavefront measure is necessary to compensate and control the wavefront of laser beam with intermediate frequency.
在高功率激光系统，激光束小尺度相位畸变波前探测是实现激光束中频段波前补偿与控制的重要前提。
3
The L3 features a linear phase crossover which doesn't introduce phasedistortion between the frequency bands. The crossover points are selectable by the user.