Device and method for detecting feeble signals of global navigation satellite system

Abstract

The invention discloses a device and a method for detecting feeble signals of a global navigation satellite system. The method comprises the following steps of: determining respective signal power and noise threshold by each detecting channel and outputting the signal power and the noise threshold to a multi-resident detector; comparing the signal power with the noise threshold by the multi-resident detector, if the signal power is higher than the noise power, the detection is successful, and then one is added on a counter; if the signal power is lower than the noise power, the detection is failed, and then one is added on a counter; repeating the steps, and judging whether the feeble signals of the global navigation satellite system are successfully detected or not by the multi-resident detector, if the detection is successful, transmitting the current code phase and a Doppler frequency point to a subsequent dynamic tracking module on the unified time point of the system to carry out dynamic synchronization; and if the detection is failed, transmitting the state information to a searching module of a unit to be detected on the unified time point of the system. By adopting the method and the device, the channel number of a detection correlator is reduced and the detection on the feeble signals of the global navigation satellite system is realized.

Description

technical field [0001] The invention relates to the technical field of signal detection of a global satellite positioning system receiver, in particular to a device and method for detecting weak signals of a global navigation satellite system. Background technique [0002] GPS satellite signal acquisition is actually a two-dimensional search and detection process, which requires a rough estimate of the code phase and Doppler frequency of the satellite signal. The two-dimensional search space defined by the uncertain range of code phase and Doppler frequency contains tens of thousands or even hundreds of thousands of signal search units, and one signal search unit is composed of one code unit and one Doppler unit. Satellite signal acquisition technology belongs to the field of signal detection. The essence of navigation signal demodulation is a joint detection and estimation problem. Parameter estimation is the basis of signal detection, and signal detection is the premise of...

AI Technical Summary

Problems solved by technology

The increase of false alarm probability will reduce the search speed

The second disadvantage is that only one maximum detection signal is output from a large number of detection results each time, which requires a high signal-to-noise ratio. In a weak signal environment, the signal-to-noise ratio can only be improved by increasing the integration time, which also increases TTFF

[0004] It can be seen that the current popular parallel capture method is difficult to achieve the advantages of serial detection because it has to treat all search results in the parallel architecture equally.

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