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The Research of the Spaceborne Multi-function Plasma Sounding System and Its Waveform Technology

Author: YaoMing
Tutor: ZhaoZhengYu
School: Wuhan University
Course: Space Physics
Keywords: Spaceborne multi-functional plasma detector Phase encoding Ambiguity function Mixed burst
CLC: V447.1
Type: PhD thesis
Year: 2010
Downloads: 103
Quote: 1
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Abstract

Spaceborne detection equipment after decades of hard exploration and efforts, is to form a more complete spectrum detector, but so far not been able to achieve a three-dimensional space-time distribution and dynamics of the inner magnetosphere plasma density characteristics of real-time detection. This article is aimed at the detection of the plasma spatial and temporal distribution and dynamics of the inner magnetosphere and topside ionosphere regional needs, design and development of a light weight, low-power, multi-functional satellite radio remote sensing system to the detection space plasma density distribution, structure, and its temporal evolution dynamics (probe parameters including amplitude, phase, frequency, Doppler frequency shift, echo distance, angle of arrival, polarization). An active detection mode, the system can be implemented magnetospheric plasma detection, measurement of the top of the ionosphere, and as HF radar to detect large-scale target on the ground; Passive detection mode to detect spatial electromagnetic radiation background environment and low-frequency plasma waves radiation; choose the right satellite orbit, multi-satellite multi-system, the implementation of network detection, real-time distribution panorama depicting near-Earth space plasma. This paper studies the different regions (including the magnetospheric cavity top of the boundary layer, cusp, plasmapause, the plasma layer and the ionosphere) detection needs detection waveform design, through the combination of hardware and software using advanced digital signal processing methods and related technologies to solve transceiver timing control, computing, data communication, data processing and other requirements, set up the receiver hardware platform, system modularity and hardware control flow design, the detection system to meet a variety of institutions compatible needs. This study not only has important scientific significance, there is significant value in engineering applications, but also for the future of our country to carry out the exploration of Mars Martian ionosphere observations provide the necessary technical reserves. In this paper, research results are summarized as follows: 1. First proposed the concept of spaceborne multi-functional plasma detection system. An active detection mode, the system can be implemented magnetospheric plasma detection, measurement of the top of the ionosphere, and as HF radar to detect large-scale target on the ground; Passive detection mode to detect spatial electromagnetic radiation background environment and low-frequency plasma waves radiation; choose the right satellite orbit, multi-satellite multi-system, the implementation of network detection, real-time distribution panorama depicting near-Earth space plasma. This paper first proposed a two-phase coding in a group of mixed Recurrence pulse burst, it solves the the uniform pulse phase encoding pulse train blind spot, with uniform pulse phase encoding pulse string of high-range resolution, high Doppler resolution, blur-detection distance, high coding gain, low-emission power all the advantages. The waveform is suitable for distant targets within the magnetosphere no blind spot detection. 3 star design in this paper set out a multi-functional plasma detection system of hardware and software integration, system research and development work in the form of software, the use of advanced digital signal processing technology to complete, so you can easily refer to the latest digital signal processing technology and radar technology research results continue to improve system performance indicators. As a result of the embedded structure, light weight, small size, low power consumption spaceborne equipment requirements. The open architecture design of the system so that the system has the possibility of complex functions, the system structure generic, flexible functions, different detection requirements may be relatively consistent hardware, the use of different software. The same hardware platform, the use of time-sharing operation both active detection and passive detection detection mode, the consistency of the system architecture makes modular design idea can well realize, so the system is more open, versatility and scalability . Each chapter of this paper is organized as follows: Chapter 1 is an introduction part. First introduced the significance of spaceborne multi-functional plasma detector, and then describes an overview of the domestic and foreign research. Describes the main work and content arrangements. Chapter 2 details the principle of the spaceborne plasma detector. Compare the similarities and differences of spaceborne plasma detection technology and ionospheric sounding. Chapter 3 describes the basics of the theory of radar signals. Details of the two-phase encoding pulse burst, pulse binary phase coded pulse train detection spaceborne multi-functional plasma detector used single pulse, uniform burst waveform. In-depth analysis and compare the timing of these waveforms, spectrum and ambiguity function. In-depth analysis and compare the timing of these waveforms, spectrum and ambiguity function, and build their own hardware platform open-loop test to be verified. Chapter 4 details the two-phase encoder pulse string, Gaussian pulse detection with varied repetition period of the pulse waveform. In-depth analysis and compare the timing of these waveforms, spectrum and ambiguity function. In-depth analysis and compare the timing of these waveforms, spectrum and ambiguity function, and build their own hardware platform open-loop test to be verified. Chapter 5 describes the overall structure of spaceborne multi-functional plasma detector. The overall system and subsystem technical indicators and in-depth analysis of the key technologies of the system to achieve the desired solution. Chapter 6 summarizes the research work of this paper, and made a further study in the future visions and perspectives.

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