Interface Configuration and Interpretation

MER and EVM calculations are performed on the constellation data according to the formulas given in ETR290-101.

SNR after equalizer

This graph represents the signal-to-noise ratio over time, typically over 256 seconds. It is useful for examining signal-to- noise trends; for example, if an alarm condition has been breached, the graph can be used to examine trends in the signal- to-noise performance before the alarm occurred.

Equalizer

This graph shows the status of the equalizer taps, and gives an

 

estimate of the channel state. If there are echoes or other time

 

related distortions on the signal, the Equalizer display will

 

display the amplitude of the corresponding tap correction values

 

versus time.

 

 

 

NOTE. The Equalizer graph amplitude values are only

 

approximate.

MER

This graph gives a time record of MER over the last 255

 

seconds.

Select the graph to be displayed from the Graph drop-down menu.

MTM400 MPEG Transport Stream Monitor User Manual

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