A High-Precision Energy-Efficient GPS Time-Sync Method for High-Density Seismic Surveys

Ruyun Tian,Yuda Chen,Jun Lin,Yuanjie Jiang,Hongyuan Yang,Linhang Zhang,Longxu Wang,Shuai Zhang,Junjie Zhang

doi:10.3390/app10113768

Abstract

Large numbers of seismic channels and high-density energy-efficient acquisition systems are the development trend of seismic instruments and have attracted high R&D interests in recent years. The combination of remote sensing and wireless sensor network technology provides superior observation capabilities for high-density seismic exploration. However, large-scale and multi-node acquisition methods place higher requirements on time synchronization performance. Seismic data with poor time synchronization will cause considerable errors in the interpretation of seismic data and even have no practical significance. Thus, the strict time synchronization performance is the prerequisite and basis for the application of cable-less storage seismograph in high-density seismic array applications. The existing time synchronization methods have high power consumption and poor time synchronization accuracy, which is not suitable for the long-time task. In addition, these methods are affected by the number of nodes and the distance. This paper presents an energy-efficient time-sharing indexed interpolation intercept method for the seismic data synchronization. The time synchronization method uses the high-precision TCXO as the main clock and records GPS time in the SD card at intervals to achieve the high-precision time-stamp for the seismic data. Then the seismic data is intercepted intermittently based on precise time stamps, which achieves the strict seismic data synchronization. Performance analysis shows that the time synchronization accuracy of the proposed method is 0.6 μs and saves 73% energy of the time-sync periods compared to the common GPS timing method. The field measurement results indicate that the time synchronization accuracy is not associated with the working time and the distance between nodes so that the proposed synchronization method is suitable for the high-density seismic survey.

Highlights

In order to meet the needs of more detailed geological structure surveys, the study of seismological methods relies on a denser seismological network, which is used to improve the resolution of seismological research and identify weak seismic phases [1]
We present a high-precision energy-efficient time-synchronization method named the time-sharing indexed interpolation intercept (T3I) method, which combines GPS and high-precision
High-densityseismic seismic array surveys be deployed in a large-scale and a long exploration period, which places strict requirements on the time synchronization environment and a long exploration period, which places strict requirements on performance the time between multiple nodes

Summary

Introduction

In order to meet the needs of more detailed geological structure surveys, the study of seismological methods relies on a denser seismological network, which is used to improve the resolution of seismological research and identify weak seismic phases [1]. Seismic exploration technology is increasingly developing in the direction of multi-channel, high-density, wide-azimuth, and high-efficiency acquisition [2]. The amount of seismic data has increased dramatically. The demand for real-time processing of huge data streams at various acquisition sites has continued to increase. The cable seismograph has bulky cables and low fieldwork efficiency, which makes.

Methods

Discussion

Conclusion