Temporal Shaping of the Pre-beam Formed RF data
The analog TGC for RF data collection is determined through
Temporal Shaping of the beam Formed RF data
A user adjustable software digital gain is calculated and applied to the beam formed RF data by the software. The software digital gain has two components, both of which are determined by the user. A depth dependent component which comes from the sliders, and an overall component. This makes the software digital gain dependent on the depth, and hence a TGC in essence.
The gain chosen by the user is Gain. Its value should be mapped to 0% to 100% in the digital gain range. In order to maintain a uniform look across different frequencies, an offset is added to this overall gain which is determined by Gain Offset. The values of these parameters are on a logarithmic scale and will be the exponent of the actual multiplicative gain. The minimum digital gain (in dB) is determined by Doppler Digital Gain Min. The size of the range of digital gains possible (in dB) is determined by Doppler Digital Gain Range.
- Gain Offset
- Doppler Digital Gain Min
- Doppler Digital Gain Range
The TGC curve is adjustable by the user by a set of sliders representing different depths from the console of the ultrasound system. This is accomplished by applying a digital TGC on the beam formed RF data. Slider values from the console are reflected in TGC Digital.
- TGC Digital
A lateral gain curve is also implemented. This parameter is used for phased array probes only. If the curve is defined in the preset, it gets applied laterally to compensate for the bright middle region. It is applied digitally per scan line. It represents half transducer, applied symmetrically.
- TGC Lateral
For more info see Gain Engine.