Patent ID: 7940212
Filing Date: 2011-05-10
Classification: G01S,H04B

Abstract:
1. A method of processing a digital signal consisting of digital samples derived from an analog input signal of a GNSS receiver, the digital signal containing at least one encoded binary sequence of chips of equal lengths, the binary sequence being characteristic of at least one GNSS satellite and consisting of repetitions of a characteristic basic sequence which extends over a basic interval, where at least one finite length compensated data sequence consisting of digital data values is derived from the digital signal and at least one correlation value for the at least one compensated data sequence and a correlation sequence derived from the characteristic basic sequence of the at least one GNSS satellite is determined, where the derivation of the compensated data sequence involves mixing of the digital signal with a first group of periodic frequency signals with pre-integration frequencies of which at least one differs from any multiple of the inverse of the basic interval to compensate at least in part for clock drift and Doppler shift, subjecting each one of a resulting first group of part-compensated digital signals to an integration over an integration interval which extends over a multiple of the length of the basic interval where subsequent samples of the part-compensated digital data signal separated by the length of the basic interval are summed up to in each case form a digital data value of a fixed length part-compensated data sequence, mixing each one of the part-compensated data sequences in the first group with at least one further periodic frequency signal having a post-integration frequency which is a multiple of the inverse of the basic interval to provide the at least one compensated data sequence.