Any extraneous signal that invades the transmission of electrical pulses or frequencies along a cable. Noise is measured as impulse or Root-Mean-Square (RMS).

• 当一个电气讯号之脉冲或频率影响到讯号缆线之讯号传输,即称为杂讯干扰,其测量单位值为峰值或均方根值。