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Constant False Alarm Rate Acquisition Algorithm for Compass B1C Signal

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China Communications 2019年第11期16卷 201-211页

作者： Wengang Li Tianrong Qian Yiwei Wang Chen Huang State Key Laboratory of Integrated Service Networks Xidian University

In order to improve the sensitivity of the Compass B1C signal acquisition for the receiver,the principle of constant false alarm rate(CFAR)is applied for the B1C pilot channel acquisition to realize the dynamic adjustment of the threshold of acquisition against the carrier to noise ratio.The non-coherent data/pilot combined acquisition algorithm for B1C signal is analyzed to make full use of the power of the B1C signal under the condition of low carrier to noise ratio.On this basis,to improve the acquisition sensitivity of the receiver,the principle of constant false alarm probability is applied for the non-coherent data/pilot combined acquisition algorithm.Theoretical analysis and simulations show that the non-coherent data/pilot combined acquisition algorithm with CFAR improves the B1C signal acquisition sensitivity of the receiver significantly,and achieves a better Receiver Operating Characteristic compared with the traditional acquisition algorithms.

关键词： B1C signal non-coherent acquisition acquisition threshold constant false alarm rate(CFAR)

Tracking algorithm of BPSK signal in low bit SNR and high dynamic scenarios

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Journal of Beijing Institute of Technology 2015年第1期24卷 118-127页

作者：王鹏陈国瑛 Beijing Institute of Electronic System Engineering the Second Academy of China Aerospace Science and Industry Corporation

A new tracking algorithm is proposed aiming at the tracking problem in low bit signal-to- noise ratio （i. e. , Eb/N0 ） scenarios, in which the bit clock regenerated by bit synchronization loop decides loop update moment. The double frequency processing and non-coherent accumulation tech- nologies are applied to eliminate the impact of data polarity inversion, and then long time accumula- tion improves the input signal-to-noise ratio of discriminator. The frequency locked loop and phase locked loop constitute a carrier loop in parallel, which can meet the high dynamic demands. The ef- fectiveness of this algorithm has been corroborated by theoretical analysis, simulation and measure- ments, and the new tracking algorithm has been used in an aerospace engineering project successfully.

关键词： tracking double frequency processing non-coherent low bit signal-to-noise ratio

MICROSTRUCTURE OF DIFFERENTLY TREATED Al-Mg-Sc-Zr ALLOYS

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Journal of Central South University 1997年第1期9卷 24-27页

作者： Jie Zhang Zhimin Yin Yonghong Zhang Yongzheng Gao Qinglin Pan 1. Department of Materials Science and Engineering Central South University of Technology 410083 Changsha China

The microstructures of different treated Al-5Mg-0.5Sc-0. 1Zr alloys have been studied with opticalmicroscopy and transmission electron microscope (TEM). coherent particles with the matrix were found inas-cast sample. composite Al3Sc/Al3Zr particles were found after 13 h homogenized treatment under 470℃.coherent precipitates pinned dislocations and low-angle grain boundaries. and then restrained recrystallization. All kinds of particles of different treatments were not larger than 40nm. After high-temperaturestabilization treatments, most particles remain coherent with the matrix. The reasons of microstructurechange at different treated conditions have been analyzed.

关键词： Al-Mg-Sc-Zr alloy microstructure Al3 (Sc,Zr) coherent and non-coherent

Comparison of Kurtosis and Fourth Power Detectors with Applications to IR-UWB OOK Systems

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International Journal of Communications, Network and System Sciences 2012年第1期5卷 43-49页

作者： Javad Taghipour Vahid Tabataba Vakili Dariush Abbasi-Moghadam 不详

On-off keying (OOK) is one of the modulation schemes for non-coherent impulse radio Ultra-wideband systems. In this paper, the utilization of the kurtosis detector (KD) and fourth power detector (FD) receivers for OOK signaling is introduced. We investigate the effect of integration interval and the optimum threshold on the performance of energy detector (ED), KD and FD receivers. The semi analytic expression of BER is obtained by using generalized extreme value distribution function for KD and FD receivers. From performance point of view, the simulation results show that FD receiver outperforms KD and ED receivers. In contrast, the sensitivity to the optimum threshold is greatly reduced in KD receiver compared to ED and FD receivers.

关键词： Ultra-Wideband (UWB) non-coherent Receiver OOK Energy Detector Kurtosis Detector Fourth Power Detector