The Effect of Intermittent Signal on the Performance of Code Tracking Loop in GNSS Receivers

Chung-Liang Chang

doi:10.1155/2011/418032

Abstract

This paper analyzes the code tracking performance in the presence of signal blanking in Global Navigation Satellite System (GNSS). The blanking effect is usually caused by buildings that obscure the signal in either a periodic or random manner. In some cases, ideal blanking is used to remove random or periodic interference. Nevertheless, the effect of temporary discontinuity of signal often leads to the tracking and position error. To analyze this problem, three types of blanking model are considered: no blanking, periodic blanking, and random blanking of the signals input into the code tracking loop. The mean time to lose lock (MTLL) is to assess the performance of code tracking system under signal blanking. Finally, the effect of steady-state tracking errors on the performance of tracking loop resulting from blanking environment is also discussed.

Highlights

The Global Navigation Satellite System (GNSS) provides information of position, velocity, and time by means of spread spectrum techniques [1, 2]
When the signal is blanked, most of the GNSS positioning methods suffer from degradation in accuracy and increase in the receiver processing time [3]
The effect of blanking on the performance of c-delay lock loop (DLL) and ncDLL has been presented in previous sections

Summary

Introduction

The Global Navigation Satellite System (GNSS) provides information of position, velocity, and time by means of spread spectrum techniques [1, 2]. When the signal is blanked, most of the GNSS positioning methods suffer from degradation in accuracy and increase in the receiver processing time [3]. Solar radio bursts caused by sunspots cause the receiver to receive blank signal for a long time [5]. The use of ideal blanking method can mitigate the effect of pulse interference on positioning performance of receiver [6, 7]. With regards to the improvement methods for blanking effect, studies in early research only determine and deal with the phenomenon prior to signal correlation [8]. When the signal suffers from blanking effect, literature review on the postprocessing of code tracking is relatively few

Objectives

Results

Conclusion