The invention discloses a
weak signal acquisition method based on an overlapping multi-block
zero padding algorithm, and a defect of coherent accumulation length and
block number invariability in an existing double-block
zero padding algorithm is mainly solved. The solution is that a received RF
signal is orderly subjected to filtering,
down conversion and digital sampling at a receiving end, and an original
baseband complex
signal is obtained; navigation data used by a sending end is subjected to
spread spectrum modulation and shaped offset quadrature
phase shift keying modulation to obtain an original local
signal; coherent accumulation extended data and a step factor are introduced, the original
baseband complex signal and the local signal are subjected to block combination, and a new
baseband complex signal data block and a new local signal data block are obtained; the new baseband complex signal data block and the new local signal data block are subjected to
circular correlation, and related value data is obtained; according to a
peak value which appears in the related value data, whether acquisition is successful is judged. According to the method, better acquisition performance can be obtained in a small
frequency offset, and the method can be used for
data transmission and
satellite positioning navigation.