| CPC H04B 1/70735 (2013.01) [H04B 1/713 (2013.01); H04L 25/03898 (2013.01)] | 6 Claims |

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1. A design method for a satellite navigation signal system with mixed modulation of direct spread spectrum and frequency hopping, wherein a navigation signal comprises multipath signal components and the method comprises:
acquiring design requirements of multipath signal components, wherein the design requirements of the multipath signal components comprise: baseband code sequence generation design, signal separation and recombination design, frequency hopping modulation design and direct spread spectrum signal generation design;
designing a baseband code sequence generation of the multipath signal components as follows: modulating a spread spectrum code sequence of the multipath signal components, followed by mixing and multiplexing with signal components corresponding to a same frequency point, and forming the baseband code sequence according to a power ratio of each path of signal components;
separating the signal components corresponding to the baseband code sequence according to navigation signal receiving environment conditions to obtain multipath separated radio frequency signals;
carrying out signal recombination modulation on the multipath separated radio frequency signals, wherein if separated radio frequency signals corresponding to a current communication path are authorized signals, a frequency hopping pattern is controlled through a frequency hopping code sequence, and a mixed frequency synthesis modulation is carried out according to a central frequency point of the frequency hopping pattern and a frequency of the authorized signals to obtain multipath modulated recombined signal components; if separated radio frequency signals corresponding to the current communication path are unauthorized signals, a direct combined radio frequency modulation is performed according to a preset signal frequency point and a frequency of the unauthorized signals to obtain multipath modulated recombined signal components; and amplifying a signal power of each path of modulated recombined signal components according to a center frequency point difference of the multipath modulated recombined signal components to obtain multipath direct spread spectrum navigation signals for transmission.
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