# NEXT Crosstalk calculation

The NEXT value for a given cable type is generally expressed in decibels per feet or decibels per 1000 feet. NEXT value varies with the frequency of transmission. The higher the NEXT value, the greater the cable’s ability to reject crosstalk at its local connection.

I'm trying to understand how one would calculate NEXT (Near-end Crosstalk). I assume the effect would be greatest at the source of the noise?

So, given some arbitrary figures:

• signal power at source 1 watt
• NEXT crosstalk 10dB/1000 feet.

I have been told that it's similar to a SNR ratio.

Does this mean that at 1000 feet, we would expect one tenth of the signal to leak to the adjacent pair?

How would one calculate the crosstalk closer to the source?

I suspect I'm missing a couple of pieces of the puzzle, any help would be greatly appreciated.

T.I.A.

• Did any answer help you? If so, you should accept the answer so that the question doesn't keep popping up forever, looking for an answer. Alternatively, you can post and accept your own answer. Jan 7 at 1:13