Code acquisition for LEO satellite mobile communication using a serial-parallel correlator with FFT for Doppler estimation
نویسندگان
چکیده
In this paper we propose a serial-parallel correlator (SPC) for the purpose of PN code acquisition in a low earth orbit (LEO) satellite environment. To reduce the effect of severe Doppler in a LEO satellite channel, we combine the SPC with an FFT technique to combat the carrier frequency offset due to Doppler shift. By using the FFT technique we omit the need for an additional search over the frequency uncertainty and therefore significantly reduce the mean acquisition time compared to standard acquisition techniques, which perform a full search over the 2-dimensional uncertainty region.
منابع مشابه
A Serial-Parallel FFT Correlator for PN Code Acquisition from LEO Satellites
A new receiver architecture for PN code acquisition of signals with high Doppler shifts is proposed, in which the partially correlated outputs of the parallel section of a serialparallel correlator (SPC) are subject to an FFT process before being summed by the serial section. In this way a wider range of frequencies can be searched in a single dwell time, which is particularly useful in a LEOS ...
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