A damage diagnosis method for ultra-long cables

Abstract

The invention discloses a damage diagnosis method for an ultra-long cable, which comprises the following steps: the Ethernet physical layer chip sends a continuous pulse signal and starts a timer T; the Ethernet physical layer chip detects the first one exceeding the threshold value A1 Reflect the pulse and record the time t1 of the timer at this time to complete the near-end reflection test; the Ethernet physical layer chip resends the continuous pulse signal and restarts the timer T; the Ethernet physical layer chip dynamically adjusts the threshold A2 according to the timer T; The Ethernet physical layer chip detects the first reflected pulse exceeding the threshold value A2 and records the time t2 of the timer at this time to complete the far-end reflection test; the position of the cable damage is obtained by calculating the difference between t2 and t1. The damage diagnosis method of the ultra-long cable of the present invention can accurately diagnose the damage of the ultra-long cable.

Description

technical field [0001] The invention relates to the technical field of communication, in particular to a damage diagnosis method for an ultra-long cable. Background technique [0002] The Ethernet cable diagnosis method can detect the cable status and damage location, wherein the cable status includes open circuit, short circuit, matching and short circuit between the cable pairs. Existing damage detection techniques such as image 3 As shown, the specific steps are as follows: [0003] The Ethernet physical layer chip (PHY) sends a pulse signal and starts a timer T; [0004] The Ethernet physical layer chip (PHY) detects the first pulse exceeding the threshold A1 and records the timer time t1; [0005] The Ethernet physical layer chip (PHY) resends the pulse signal and restarts the timer T; [0006] The Ethernet physical layer chip (PHY) detects the first pulse exceeding the threshold A2 and records the timer time t2; [0007] The location of the cable damage is obtaine...

AI Technical Summary

Problems solved by technology

[0009] In the above detection method, when the cable is very long, the far-end reflection signal is very weak. When the amplitude of the reflection signal is lower than the threshold value A2, the cable status cannot be detected.

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