Passive optical network data collection method based on secondary sampling

Abstract

The present invention discloses a passive optical network data collection method based on secondary sampling. The method comprises the following steps that: an OLT periodically generates synchronization time information according to a first local clock counter; the OLT carries out ranging on an ONU, obtains a loop time delay and sends the time delay to the ONU; the ONU outputs synchronization sampling pulse according to received time information; the ONU latches the value of a second local clock counter at the rising edge of the synchronization sampling pulse; the sampling values of N periods before the synchronization sampling pulse are obtained through cache; the ONU sends the values to an interpolation module to carry out interpolation operation to obtain a synchronization sampling interpolation result and outputs the interpolation result at the falling edge of the synchronization sampling pulse, the result can be sent to an ONU local processor to carry out processing to realize data synchronous acquisition and transmission, the establishment of a time synchronization relation among multiple passive optical networks is not needed according to the provided method, the independent sampling frequency can be employed by each passive optical network, and stable and reliable synchronization collection data is obtained.

Description

technical field [0001] The invention relates to the technical field of communication, in particular to a data collection method of a passive optical network. Background technique [0002] Passive Optical Network (PON) system is a new type of optical fiber access network technology that appeared in the early 1990s. It is a typical point-to-multipoint transmission. The central office equipment (optical line terminal, OLT) and multiple users The network connected by the Optical Distribution Network (ODN) composed of passive optical cables, optical splitters / combiners, etc. , Flexible and convenient application. [0003] The work of the existing information collection and communication system mainly depends on multi-point data information and unified and accurate time reference information in the system, especially for a large number of synchronous data collection and transmission in the system, which requires synchronization, real-time and reliability. However, there are more...

AI Technical Summary

Problems solved by technology

However, there are more or less problems in the traditional synchronous data acquisition (for example, the area protection of the intelligent distribution network system) communication technology, especially when multiple hosts need to sample the synchronous data, it is required to maintain time synchronization between the hosts The relationship between traditional time synchronization technologies such as IRIG-B code time synchronization with GPS / Beidou as the reference time, 1PPS time synchronization based on the second pulse or IEEE-1588 time synchronization based on Ethernet, although these methods can complete time synchronization, but There are problems such as low time synchronization accuracy, poor reliability, difficult management and maintenance, and high networking costs

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