Comparison between Galileo CBOC Candidates and BOC(1,1) in Terms of Detection Performance

Fabio Dovis,Maurizio Fantino,Jérémie Godet,Paolo Mulassano,Letizia Lo Presti

doi:10.1155/2008/793868

Abstract

Many scientific activities within the navigation field have been focused on the analysis of innovative modulations for both GPS L1C and Galileo E1 OS, after the 2004 agreement between United States and European Commission on the development of GPS and Galileo. The joint effort by scientists of both parties has been focused on the multiplexed binary offset carrier (MBOC) which is defined on the basis of its spectrum, and in this sense different time waveforms can be selected as possible modulation candidates. The goal of this paper is to present the detection performance of the composite BOC implementation of an MBOC signal in terms of detection and false alarm probabilities. A comparison among the CBOC and BOC(1,1) modulations is also presented to show how the CBOC solution, designed to have excellent tracking performance and multipath rejection capabilities, does not limit the acquisition process.

Highlights

The agreement reached in 2004 by United States (US) and European Commission (EC) [1] focused on the Galileo and GPS coexistence clearly stated as central point to the selection of a common signal in space (SIS) baseline structure that is the BOC(1,1)
The results show that from the acquisition standpoint, thanks to the 10/11th of power located to a BOC(1,1) in the multiplexed binary offset carrier (MBOC) spectrum, the compatibility with the state-of-the-art BOC(1,1) receiver baseline is assured
On the basis of the modernization activities around the future Galileo E1 signals, this paper focuses on the analysis of the acquisition detection performance of two composite BOC (CBOC) solutions, which are the CBOC(6,1,1/11) and CBOC(6,1,4/33)

Summary

INTRODUCTION

The agreement reached in 2004 by United States (US) and European Commission (EC) [1] focused on the Galileo and GPS coexistence clearly stated as central point to the selection of a common signal in space (SIS) baseline structure that is the BOC(1,1). Regardless the kind of CBOC, such a signal structure allows the receivers to obtain high performance in terms of multipath rejection and tracking [4, 5]. This is mainly due to a higher transition rate brought by the BOC(6,1) on top of the BOC(1,1). The paper is organized as follows: Section 2 reports the main features of the MBOC approach while Section 3 presents the correlations properties as well as the possible CBOC candidates in terms of power allocation.

MBOC DEFINITION AND SPECTRUM CHARACTERISTICS

CBOC FEATURES

ACQUISITION OF THE OPTIMIZED CBOC SIGNAL

DETECTION PERFORMANCE OF THE CBOC MODULATION CANDIDATES

Findings

CONCLUSIONS