X-ray pulsar photon signal ground simulation system with high time-frequency stability

Abstract

The invention discloses an X-ray pulsar photon signal ground simulation system with high time-frequency stability, comprising a program control computer, a high time-frequency stability signal source, an electric control visible light source, an adjustable optical attenuator, an optical shielding cavity, a photomultiplier and an electronic reading circuit. The high time-frequency stability signal source is used for obtaining a pulsar cycle and outline data output by the program control computer, generating a trigger signal to synchronize the electronic reading circuit, generating a high time-frequency stability voltage, inputting the voltage to the electric control visible light source and controlling the electric control visible light source to generate the visible light with light power which is in direct proportion with the input voltage, wherein the visible light is attenuated into photon stream by the adjustable optical attenuator; the photomultiplier detects out that the photo stream generates electric pulse, calibrates the electric pulse by the electronic reading circuit and then outputs to the program control computer. The system has the advantages of high simulation reliability, high outline precision and high time precision and can be used as an experimental device for timing observation, weak signal treatment and navigation design.

Description

technical field [0001] The invention belongs to the technical field of signal processing, in particular to an X-ray pulsar photon signal ground simulation system, which simulates the X-ray pulsar photon signal received by a detector in a space environment, and can be used for timing observation, weak signal processing and navigation algorithm design important experimental device. Background technique [0002] A pulsar is a high-speed rotating, highly magnetized "extreme" celestial body with a short rotation period and high stability. These characteristics make it possible to use pulsars for navigation and timing in deep space. However, because pulsars are generally hundreds to hundreds of thousands of light years away from the earth, the X-ray pulse signal attenuation is relatively serious, and the flow is very weak when it reaches the X-ray detector. At the same time, due to the influence of cosmic rays and the performance of the detector itself, the The received signal is...

AI Technical Summary

Problems solved by technology

[0006]a. The periodic stability achieved by mechanical rotation is generally 10-3-10-5 , which is far from the typical period stability of pulsars of 10-10-10-12, when using these two simulation systems to fold photon arrival time by period, the pulse The peak will be widened, the signal noise will become stronger, and the TOA estimation error will be larger, which will directly affect the subsequent algorithm processing and navigation effect

[0007]b. The precision of mechanical processing is limited, making it difficult to simulate the unique contour features of pulsars by machining gaps on the disk, and even lose the details of the pulse contour part, the accuracy is low, and different disks need to be replaced when simulating different pulsar profiles, and the flexibility is low

[0008] c. There is an upper limit to the speed of mechanical rotation. When simulating some millisecond pulsars with a short period, such as PSRB1937+21 with a period of 1.56ms, if mechanical rotation is used way, the speed will reach 40000rpm, the difficulty of simulation is great

[0009]2. The third type of simulation system simulates the pulsar signal in a purely electrical way. This device improves the contour accuracy of the signal simulation, but the pulsar signal is generated by Generated by computer programs, which are essentially software simulations, and the simulation reliability is low

[0010]3. The fourth type of device focuses on background environment simulation, using the real atmosphere to simulate the space environment of pulsar signal transmission. The problem brought by this device is that the simulation The detector has high requirements on the atmospheric environment, the ambient light cannot be continuously adjusted, the influence of the weather makes the test conditions unrepeatable, and the strong light condition has a great impact on the laser receiver, and the system debugging is difficult, which brings great difficulties to the signal analysis and processing. great inconvenience

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