Pulsar Signal Pattern Recognition And Processing

With the range expansion of the human exploration to the unknown areas,spacecraft autonomous navigation is of the increasingly high demands for thedeep space exploration. In order to realize autonomous navigation, humans needto build a pure natural celestial navigation system. The pulsars which was firstdiscovered in1980s have the stable period and suitable sky geometricdistribution. These characteristics offer the possibility to build autonomousnavigation system for the human spacecraft. Pulsar navigation key technology isthe detection and identification of pulsar signals. Aimed to the pulsar signalcharacteristics, this paper presents a new type of pulsar signal detector with thefeatures of low power consumption and volume miniaturization This paperintroduces the concept of the characteristic frequency to the pulsar signalrecognition. And on the basis of the recognition, the paper completes thesignificant parameter estimation of TOA (Time of arrival). It is avoiding theshortcomings of long-term accumulation in the methods of traditional pulsaridentification and achieves the real-time detection.Firstly, the paper introduces the characteristics of pulsar signals andanalysis the merits and the possibility that pulsar is applicable to the autonomousnavigation.According to the characteristics of pulsar signals, the paper designs a newtype of detector-SEED. This paper analyzes the detection principle of SEEDdetectors, and completes the theoretical design of the detector. The papercompletes the electrical IC simulation of a detection unit. In the research itbuilds the math model for the SEED detector and made the functional simulation.Through the simulation result this new pulsar detector can achieve the functionof the pulsar with the features of Miniaturization and low power consumption.To achieve the pulsar autonomous navigation, the key technologies arepulsar signal indemnification and the estimation of the signal parameter TOA.This paper introduces the concept of a pulsar characteristic frequency andnarrowband filtering.The complex pulsar signal processing transforms to a characteristic frequencysignal processing. It reduces the effects of noise on the signal processing by the pulsar matched filter. It achieves the real-time detection and TOA estimationparameters pulsar signal. In order to improve the effect of characteristicfrequency detection, this paper proposes a method to detect the neighborhood ofthe characteristic frequency which can improve the effectiveness and accuracy ofdetection of the characteristic frequency of the pulsar. Compared with squarewave transform and cepstrum processing, the method in the article has goodperformance in the phase processing and noise resistance.In order to complete the spacecraft signal detection of the pulsar, the pulsarorientation required to be completed on the spacecraft. This paper presents apulsar vector measurement principle based on information fusion. It is a datafusion algorithm based on least squares method After the simulation, the resultverifies that this method can improve the accuracy of pulsar vectormeasurements.