| 摘要 |
<p>A digital data compression apparatus particularly for use in electrical power fault data recorders, comprising an envelope detection unit (36) and a data compression unit (40). Envelope control signal lines (41) are originated from the data input motherboard (28) and allow selection between signals representing the positive peaks, the negative peaks and the input waveform itself. These positive and negative peak signals are sampled at a first sampling period and compressed by dynamic gain ranging in the data compression unit. The input waveform is sampled at a second sampling period and compressed by both dynamic gain ranging and time decimation.</p> |
