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In this paper, we propose a method based on applying specific transformations to the Global Navigation Satellite System (GNSS) signals received in unfavorable environment. As a result, one simple classical receiver including these adjustments becomes sensitive to several Multi-Constellation and Multi-Frequency (MC/MF) GNSS signals and achieves efficiently their collective acquisition. The proposed method consists of three variants each dedicated to a particular type of Binary Offset Carrier (BOC) family signals; the primary is based on undersampling process, the second is founded on time expansion and the last one permits the acquisition of more than five different GNSS signals by a single local Composite Binaiy Coded Symbols (CBCS) waveform replica. Hence, the proposed scheme, by avoiding the use of multiple demodulators in the baseband, allows less receiver complexity and accordingly better realization cost. The simulation results showed that the proposed method presents an effective solution for the reception of MC/MF signals in unfavorable environments. [ABSTRACT FROM AUTHOR]

The modernized Global Positioning System (GPS) and Galileo satellite navigation systems have recommended the interoperable Multiplexed-Binary Offset Carrier (MBOC) modulation on L1C/E1 frequency band for their open service signals. MBOC signal multiplexes BOC( 6 , 1 ) and BOC( 1 , 1 ) according to a certain proportion, and can be implemented in a number of ways, including Composite BOC (CBOC) and Time-Multiplexed BOC (TMBOC). The complexity and the accuracy of the theoretical signal modeling pose a growing concern to scrutinize and to optimize signal characteristics and receiver performances. In this paper, the analytical expressions of the optimal correlation function (CF) for the new modernized MBOC signal are proposed. Also derived are the analytical models of the discriminator functions (DFs) and the multipath error envelopes (MEEs) in both coherent and non-coherent code tracking configurations. The validation of the proposed models is performed and the simulation results show that the proposed analytical models coincide with the numerical ones. [ABSTRACT FROM AUTHOR]