Overhead optical cable test system and method

An analysis apparatus including one or more processors configured to:

• receive a vibration distribution waveform which is acquired from an overhead optical fiber cable to be tested and is represented in a time domain and a distance domain in a longitudinal direction;
• calculate a propagation speed of vibrations propagating through the overhead optical fiber cable from the vibration distribution waveform;
• and
• detect, as a cable sag section, a section of the overhead optical fiber cable in which the propagation speed is equal to or lower than a threshold value.

A cable test method comprising:

• acquiring a vibration distribution waveform of an overhead optical fiber cable to be tested, the vibration distribution waveform being represented in a time domain and a distance domain in a longitudinal direction;
• calculating a propagation speed of vibrations propagating through the overhead optical fiber cable from the vibration distribution waveform;
• and
• detecting, as a cable sag section, a section of the overhead optical fiber cable in which the propagation speed is equal to or lower than a threshold value.