repetition period

For underwater acoustic positioning system based on measurement of time_delay, range ambiguity appears when pulse's propagating time is longer than its repetition period.

At present stage in China, tourism in rural areas is one for leisure, with the characteristics of short period, short trip, low consumption and repetition.

In contrast to traditional shipbuilding mode, this method can sharply lower the rate of repetition and material wasting in pipe design and arrangement period.