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In global navigation satellite system (GNSS) receivers, the first signal processing stage is the acquisition, which consists of detecting the received GNSS signals and determining the associated code delay and Doppler frequency by means of correlations with a code and carrier replicas. These codes, as part of the GNSS signal, were chosen to have very good correlation properties without considering...
The acquisition of global navigation satellite system signals can be performed using a fast Fourier transform (FFT). The FFT-based acquisition performs a circular correlation, and is thus sensitive to potential transitions between consecutive periods of the code. Such transitions are not occurring often for the GPS L1 C/A signal because of the low data rate, but very likely for the new GNSS signals...
There are mainly three well-known techniques to acquire a GNSS signal. The first, called Serial Search Acquisition, consist in correlating the Pseudo-Random Noise (PRN) codes for all the codes phases and all the frequency bins. The two others make use of the Fourier Transform in order to parallelize the search, either in the frequency space (Parallel Frequency Space Search Acquisition) or in the code...
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