项目名称： 类噪声chirp扩频测控信号波形设计与接收技术研究

项目编号： No.61501031

项目类型： 青年科学基金项目

立项/批准年度： 2016

项目学科： 无线电电子学、电信技术

项目作者： 郇浩

作者单位： 北京理工大学

项目金额： 21万元

中文摘要： 快速建链通信是Ka频段天基平台（比如TDRSS）测控运载火箭、中低轨道飞行器的一项关键技术。它主要面临中继卫星与飞行器天线双向扫描捕获的时间短、接收信号信噪比低、多普勒频偏大、多普勒动态范围大等难题。传统直接序列扩频信号，其接收机终端在低信噪比环境下需要进行多次较大范围的伪码相位—多普勒二维搜索来完成信号捕获，难以满足对于运载火箭等需要全程测控、实时性要求高的应用场景。本项目从测控信号波形设计角度入手，利用chirp信号多普勒容限大的特点，通过对其加入相位随机扰动，提出了一种谱密度低、多普勒容限大的类噪声chirp测控信号扩频方式，从根本上减少多普勒搜索单元，大幅降低捕获时间。项目通过深入研究其①波形设计方法，②基于正交匹配滤波的快速捕获技术，③多普勒变化率估计值辅助的高动态载波跟踪技术等，力争为我国Ka频段天基测控技术的发展提供技术储备。

中文关键词： 测控；混合扩频；大频偏；快速捕获；跟踪

英文摘要： Fast establishment method of communication link (FEMCL) , as a key technique for launch vehicle and low earth-orbiting spacecraft via the next generation Ka-band space-based TT&C system, i.e. tracking and data acquisition relay satellite system (TDRSS), is mainly exposed to a series of technical problems. Such as short captured time of satellite and aircraft antenna bidirectional scanning, low received signal to noise ratio (SNR), large Doppler shift and Doppler dynamic range. Aiming at completing signal acquisition in low SNR, the receiver of traditional direct sequence spread spectrum signal (DSSS) requires two dimensional searching for pseudo-code phase and Doppler shift though many times, which hardly meets the needs of real-time monitoring scenarios. Based on the need of new TT&C signal waveform design and the characteristics of large Doppler tolerance of chirp signal, the project proposes a novel chirp noise waveform (CNW) with low spectral density and large Doppler tolerance by embedding pseudo-phase to the original chirp signal, which results in reducing the Doppler search unit and decreasing acquisition time dramatically. The project focuses on researching three key techniques: novel TT&C signal waveform design method, fast acquisition strategy based on orthogonal matched filters, high dynamic carrier tracking loop assisted by estimation of Doppler rate. Based on these techniques, we strive to provide technical storage for the development of Ka-band space-based TT&C systems.

英文关键词： TT&C;hybrid spread spectrum;large doppler offset;fast acquisition;tracking