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An Approach for GPS Clock Jump Detection Using Carrier Phase Measurements in Real-Time

  • Heo, Youn-Jeong ;
  • Cho, Jeong-Ho ;
  • Heo, Moon-Beom
  • Received : 2011.01.01
  • Accepted : 2011.11.18
  • Published : 2012.05.01

Abstract

In this study, a real-time architecture for the detection of clock jumps in the GPS clock behavior is proposed. GPS satellite atomic clocks have characteristics of a second order polynomial in the long term showing sudden jumps occasionally. As satellite clock anomalies influence on GPS measurements which could deliver wrong position information to users as a result, it is required to develop a real time technique for the detection of the clock anomalies especially on the real-time GPS applications such as aviation. The proposed strategy is based on Teager Energy operator, which can be immediately detect any changes in the satellite clock bias estimated from GPS carrier phase measurements. The verification results under numerous cases in the presence of clock jumps are demonstrated.

Keywords

GPS;Satellite clock anomaly;Clock jump detection;Teager energy

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