Attenuation-to-crosstalk ratio (ACR) is a parameter that is measured when testing a communication link, which represents the overall performance of the cable.
[1] AcR is a mathematical formula that calculates the ratio of attenuation to near-end crosstalk for each combination of cable pairs.
[2] ACR is expressed as a figure in decibels (dB), between the signal attenuation produced by a wire or cable transmission medium and the near-end crosstalk (NEXT).
[3] In order for a signal to be received with an acceptable bit error rate, the attenuation and the crosstalk must both be minimized.
[4] The maximum frequency for which positive ACR is assured provides a benchmark to assess the usable bandwidth of twisted-pair cabling systems.