34results about How to "High signal-to-noise ratio gain" patented technology

The invention discloses a method and a device for capturing navigation signals. The method comprises steps: to-be-processed data segments are selected, the to-be-processed data segments are delayed sequentially for a delay step, and N data groups are obtained; the coherent integral value of each data group is acquired, and the first largest coherent integral value, a left neighbor coherent integral value and a right neighbor coherent integral value are determined; when the absolute value of the difference between the left neighbor coherent integral value and the right neighbor coherent integral value is smaller than or equal to a threshold value, the first largest coherent integral value is determined to be the coherent integral value not including navigation data bit hopping and can be used for capturing and deciding the navigation signals; and when the absolute value of the difference between the left neighbor coherent integral value and the right neighbor coherent integral value is larger than the threshold value, through comparing the left neighbor coherent integral value and the right neighbor coherent integral value, a fine searching direction is determined, and through the fine searching, the coherent integral value not including the navigation data bit hopping is determined. Thus, the computational efficiency during the navigation signal capturing process can be improved, and the signal-to-noise ratio gains are improved.

The invention belongs to the PN code FFT parallel acquisition method in wireless communication technology, including: the generation of the short pseudocode set at the transmitting end, the generation of baseband modulation signals, the up-conversion processing and signal transmission; the generation of the short pseudocode set at the receiving end, signal reception and Down conversion processing, frequency domain matching for correlation, large number judgment. The invention converts the long pseudo-code into G short pseudo-codes, and each short pseudo-code is cascaded to generate a short pseudo-code set; the receiver simultaneously uses the same cascaded short pseudo-code set to perform frequency domain matching related processing , and then use a large number of decisions based on chip delay; thus, it has little sensitivity to channel noise, does not need accurate channel estimation and high acquisition accuracy, and uses a large number of decisions to improve the robustness of the decision criterion Features. In the Rayleigh channel, when the acquisition probability of the invention is 95%, the required signal-to-noise ratio is about -13dB, which is about -1dB compared with the required signal-to-noise ratio of the background technology, and the gain of the signal-to-noise ratio is increased by about 12dB.