Maximum likelihood multipath estimation in comparison with conventional delay lock loops

Research output: Contribution to conferencePaper, not in proceeding


The implementation of the maximum likelihood estimator
for the time-delay estimation problem is practically
intractable for navigation signals due to its complexity,
especially when due to multipath reception several
superimposed replica are taken into account. Recently it
has been shown that signal compression techniques can
overcome this problem, as the maximum likelihood
estimator can be formulated efficiently upon a reduced
data set of much smaller size compared to the original
data, where the reduced data set forms a sufficient statistic
for the estimated signal parameters. This paper focuses on
the formulation of such a signal compression based
estimator. Furthermore the integration of the estimator
into navigation receivers is addressed, in particular by
considering the delay lock loop architecture that is
employed within conventional navigation receivers. A
novel approach for integrating the efficient maximum
likelihood estimator into a generic tracking loop is
proposed. The performance of the proposed method is
assessed by computer simulations. The results show that
the conventional delay lock loop is outperformed with respect to noise performance as well as with respect to the
multipath bias.


External organisations
  • External Organization - Unknown
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Electrical Engineering, Electronic Engineering, Information Engineering


  • GNSS, multipath mitigation, delay lock loop, DLL
Original languageEnglish
Publication statusPublished - 2006
Publication categoryResearch
EventInternational Technical Meeting of the Institute of Navigation Satellite Division, (ION GNSS), 2006 - Forth Worth, TX, United States
Duration: 2006 Sep 252006 Sep 26


ConferenceInternational Technical Meeting of the Institute of Navigation Satellite Division, (ION GNSS), 2006
CountryUnited States
CityForth Worth, TX