In: Physics
Assuming all other factors remain the same, if pulse repetition frequency increases discuss what will happen to the spatial pulse length
As frequency increases comment on what happens to back scatter
Pulse
Pulse can be defined as the single vibration of sound. we know that sound can travel only through matter by the form of vibration. It can't be transmitted through a vacuum as radiation. It posses frequency, wavelength, and all other characteristics of a wave.
Pulse repetition frequency and it's period.
Pulse repetition frequency can be defined as the number of pulses per second in pulsed ultrasound waves. its unit will be expressed in kHz.
Pulse repetition period is the time taken from the beginning of one pulse to the beginning of another pulse in a pulsed waveform. Pulse repetition period will decrease with an increase in the pulse repetition frequency because higher frequency will decrease the time duration for the next pulse generation.
Spatial pulse length.
The spatial pulse length can be defined as the length of a pulse in a pulsed waveform. It can be measured from the front of a pulse to the back of the same pulse. its unit can be expressed in mm.
The relation between Pulse repetition frequency and Spatial pulse length.
From the above description, it is clear that spatial pulse length will not get affected by pulse repetition frequency because spatial pulse length will only be affected by the frequency of the wave as the frequency increase the wavelength gets decreases and thus the spatial length get decreases. So if the other factors remain the same then the increase in pulse repetition frequency will not affect spatial pulse length, it will remain the same.
Backscatter.
When an ultrasound wave propagates through the matter, the ability of the ultrasound wave can be determined by two parameters, that is the ability of the ultrasound to passes through the matter or the energy transferred and the other is the part of energy scattered to the surrounding by striking the obstacles in the path. This scattering of energy is called the backscattering.
The relation between frequency and backscatter.
The frequency is directly proportional to the backscatter coefficient of the medium, that is higher the frequency higher will be the backscatter volume.