ML estimator and hybrid beamformer for multipath and interference mitigation in GNSS receivers
| Autor: | Seco Granados, Gonzalo, Fernández Rubio, Juan Antonio, Fernández Prades, Carlos |
|---|---|
| Přispěvatelé: | Universitat Politècnica de Catalunya. Departament de Teoria del Senyal i Comunicacions, Universitat Politècnica de Catalunya. SPCOM - Grup de Recerca de Processament del Senyal i Comunicacions |
| Jazyk: | angličtina |
| Rok vydání: | 2005 |
| Předmět: |
Signal processing
Hybrid beamformer Code division multiaccess Iterative methods Antenes -- Agrupacions Compatibilitat electromagnètica Maximum likelihood principle Spread spectrum communication Processament del senyal Delay estimation Global Positioning System Iterative algorithm Satellite navigation system Antenna arrays Interference migration Multipath channel Artificial satellites in telecommunication Adaptive signal estimation Pseudorandom code ML estimator Interference mitigation Radio receivers Satellite navigation Phase estimation Direct-sequence spread-spectrum satellite transmitter Mean squared error method Multipath propagation Gaussian channel Channel coding Enginyeria de la telecomunicació::Processament del senyal [Àrees temàtiques de la UPC] Computational complexity Code-phase estimation Satèl·lits artificials -- Comunicacions Radio navigation Array signal processing Calibration Interference suppression Radiofrequency interference Radio receiver Early-late estimator Electromagnetic compatibility GNSS receiver Direction-of-arrival estimation Carrier-phase estimation |
| Zdroj: | UPCommons. Portal del coneixement obert de la UPC Universitat Politècnica de Catalunya (UPC) Recercat. Dipósit de la Recerca de Catalunya instname |
| Popis: | This paper addresses the estimation of the code-phase(pseudorange) and the carrier-phase of the direct signal received from a direct-sequence spread-spectrum satellite transmitter. The signal is received by an antenna array in a scenario with interference and multipath propagation. These two effects are generally the limiting error sources in most high-precision positioning applications. A new estimator of the code- and carrier-phases is derived by using a simplified signal model and the maximum likelihood (ML) principle. The simplified model consists essentially of gathering all signals, except for the direct one, in a component with unknown spatial correlation. The estimator exploits the knowledge of the direction-of-arrival of the direct signal and is much simpler than other estimators derived under more detailed signal models. Moreover, we present an iterative algorithm, that is adequate for a practical implementation and explores an interesting link between the ML estimator and a hybrid beamformer. The mean squared error and bias of the new estimator are computed for a number of scenarios and compared with those of other methods. The presented estimator and the hybrid beamforming outperform the existing techniques of comparable complexity and attains, in many situations, the Cramér–Rao lower bound of the problem at hand. |
| Databáze: | OpenAIRE |
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