A non-coherent architecture for GNSS digital tracking loops



In this paper, a new, noncoherent architecture for global navigation satellite system tracking loops is proposed and analyzed. A noncoherent phase discriminator, able to extend the integration time beyond the bit duration, is derived from the maximum likelihood principle and integrated into a Costas loop. The discriminator is noncoherent in the sense that the bit information is removed by using a nonlinear operation. By jointly using such a discriminator and noncoherent integrations at the delay lock loop level, a fully noncoherent architecture, able to operate at low carrier-power-to-noise density ratio (C/N0), is obtained. The algorithms proposed have been tested by means of live GPS data and compared with existing methodologies, resulting in an effective solution for extending the total integration time.


Coherent integration Global navigation satellite system GNSS Long integration Loop discriminators Noncoherent integration Tracking loops Weak signals 



The authors would like to kindly acknowledge and thank Defence Research and Development Canada (DRDC) for funding this work.


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Copyright information

© Institut TELECOM and Springer-Verlag 2009

Authors and Affiliations

  1. 1.Department of Geomatics EngineeringUniversity of CalgaryCalgaryCanada

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