User's Manual

ISO 9001:2000 Cert. N°4500/1
Version 1.1 SDT_ARK6_User_Manual_ENG_vATSC Page 66 of 206
5.8 Manual compensation
5.8.1 Linear Precorrection
Click on Linear Precorrection button, highlighted in the next figure, to access the filter window.
Figure 27. Adaptive Linear Precorrection
The ARK6 system provides a pre-correction tool for Module&Phase output signal pre-correction.
This tool provides two grids for the drawing of:
 Module of the filter’s curve.
 Group Delay of the filter’s curve.
The two curves are used to calculate the linear pre-correction coefficients. The curves are drawn by the
interpolation of 1024 points referring to the points inserted and using a linear or polynomial
interpolation algorithm.
Knob points can be added with a left-click of the mouse on the grid and deleted with a right-click, drag
and move a point to change the curve.
Each coefficient variation, due to curves change, is saved in the FPGA “runtime” memory registers and
dynamically changes the device’s output.
The tool is prevented to send an “overflowing” amount of data to the device: curve changes will be
applied only when the mouse button is released.