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Jamming Effect Analysis of Two Chinese GNSS BeiDou-II Civil Signals
Jeehyeon Baek,Seungsoo Yoo,Sun Yong Kim
International Journal of Electrical and Computer Engineering , 2012, DOI: 10.11591/ijece.v2i6.1815
Abstract: Threats of electronic warfare, especially to global positioning systems (GPSs), have been rapidly increasing. The development of the Chinese navigation satellite system BeiDou has been extended to a global navigation satellite system (GNSS). In December 2011, the Chinese government released a specification document—a test version of a civil BeiDou-II signal called B1(I). A strong possibility exists that BeiDou-II (Chinese GNSS) will be adopted by North Korea in the near future. Therefore, research on BeiDou-II is essential. Since BeiDou-II is a newly-built system, few jamming effect analyses of its positioning signals have been performed. Thus, in this study, we analyze quality factors (Q) and the tolerable jamming signal power among two BeiDou-II civil signals, and two GPS civil signals, in three jamming conditions: band-limited white noise (BLWN), matched spectrum (MS), and continuous wave (CW). In addition, we present each jamming propagation range.
Precise Point Positioning with the BeiDou Navigation Satellite System  [PDF]
Min Li,Lizhong Qu,Qile Zhao,Jing Guo,Xing Su,Xiaotao Li
Sensors , 2014, DOI: 10.3390/s140100927
Abstract: By the end of 2012, China had launched 16 BeiDou-2 navigation satellites that include six GEOs, five IGSOs and five MEOs. This has provided initial navigation and precise pointing services ability in the Asia-Pacific regions. In order to assess the navigation and positioning performance of the BeiDou-2 system, Wuhan University has built up a network of BeiDou Experimental Tracking Stations (BETS) around the World. The Position and Navigation Data Analyst (PANDA) software was modified to determine the orbits of BeiDou satellites and provide precise orbit and satellite clock bias products from the BeiDou satellite system for user applications. This article uses the BeiDou/GPS observations of the BeiDou Experimental Tracking Stations to realize the BeiDou and BeiDou/GPS static and kinematic precise point positioning (PPP). The result indicates that the precision of BeiDou static and kinematic PPP reaches centimeter level. The precision of BeiDou/GPS kinematic PPP solutions is improved significantly compared to that of BeiDou-only or GPS-only kinematic PPP solutions. The PPP convergence time also decreases with the use of combined BeiDou/GPS systems.
Research of Anti-jamming Characteristic for BOC Signal
BOC调制信号的抗干扰性能研究

YANG Li,BO Yu-Ming,TIAN Ming-Hao,
杨力
,薄煜明,田明浩

计算机科学 , 2008,
Abstract: Binary-Offset-Carrier waveforms will be applied widely in the spreading communication, so based on the deeply research on power spectra and autocorrelation characteristic of BOC waveforms and the deeply analysis on the advantage compare to the BPSK waveforms, the FFT in-phase acquisition ring has been designed and simulated, besides, the acquisition ability of this two waveforms on the different J/S is analyzed. The result shows that the BOC waveforms have the better anti-jamming ability in the given condit...
Experimental Study on the Precise Orbit Determination of the BeiDou Navigation Satellite System  [PDF]
Lina He,Maorong Ge,Jiexian Wang,Jens Wickert,Harald Schuh
Sensors , 2013, DOI: 10.3390/s130302911
Abstract: The regional service of the Chinese BeiDou satellite navigation system is now in operation with a constellation including five Geostationary Earth Orbit satellites (GEO), five Inclined Geosynchronous Orbit (IGSO) satellites and four Medium Earth Orbit (MEO) satellites. Besides the standard positioning service with positioning accuracy of about 10 m, both precise relative positioning and precise point positioning are already demonstrated. As is well known, precise orbit and clock determination is essential in enhancing precise positioning services. To improve the satellite orbits of the BeiDou regional system, we concentrate on the impact of the tracking geometry and the involvement of MEOs, and on the effect of integer ambiguity resolution as well. About seven weeks of data collected at the BeiDou Experimental Test Service (BETS) network is employed in this experimental study. Several tracking scenarios are defined, various processing schemata are designed and carried out; and then, the estimates are compared and analyzed in detail. The results show that GEO orbits, especially the along-track component, can be significantly improved by extending the tracking network in China along longitude direction, whereas IGSOs gain more improvement if the tracking network extends in latitude. The involvement of MEOs and ambiguity-fixing also make the orbits better.
Estimating Zenith Tropospheric Delays from BeiDou Navigation Satellite System Observations  [PDF]
Aigong Xu,Zongqiu Xu,Maorong Ge,Xinchao Xu,Huizhong Zhu,Xin Sui
Sensors , 2013, DOI: 10.3390/s130404514
Abstract: The GNSS derived Zenith Tropospheric Delay (ZTD) plays today a very critical role in meteorological study and weather forecasts, as ZTDs of thousands of GNSS stations are operationally assimilated into numerical weather prediction models. Recently, the Chinese BeiDou Navigation Satellite System (BDS) was officially announced to provide operational services around China and its neighborhood and it was demonstrated to be very promising for precise navigation and positioning. In this contribution, we concentrate on estimating ZTD using BDS observations to assess its capacity for troposphere remote sensing. A local network which is about 250 km from Beijing and comprised of six stations equipped with GPS- and BDS-capable receivers is utilized. Data from 5 to 8 November 2012 collected on the network is processed in network mode using precise orbits and in Precise Point Positioning mode using precise orbits and clocks. The precise orbits and clocks are generated from a tracking network with most of the stations in China and several stations around the world. The derived ZTDs are compared with that estimated from GPS data using the final products of the International GNSS Service (IGS). The comparison shows that the bias and the standard deviation of the ZTD differences are about 2 mm and 5 mm, respectively, which are very close to the differences of GPS ZTD estimated using different software packages.
Research on One New Blanket Jamming Technology and Tactics
一种新的压制性干扰技战术研究

Shen Yang Li Xiu-he Chen Yong-guang,
沈阳
,李修和,陈永光

电子与信息学报 , 2008,
Abstract: The efficiency of broad band barrage Stand-Off Jamming (SOJ) is decreased quickly with such techniques as radar ultra-low sidelobe antennas and narrow-channel filter. In allusion to this situation, the weakness of SOJ and Electronic Counter-CounterMeasure (ECCM) of modern radar against blanket jamming are analyzed firstly. Then, a blanket Stand-Forward Jamming (SFJ) method with close-in mainlobe jamming tactics and coherent phase jamming technique is suggested to apply. This paper puts forward a principle block diagram of the jammer and designs jamming mode and signal in detail as well. Furthermore, it investigates the characteristics of power and time-frequency of this jamming technique. Computer simulation indicates that this jamming technique is superior to broad band barrage SOJ.
A Strapdown Interial Navigation System/Beidou/Doppler Velocity Log Integrated Navigation Algorithm Based on a Cubature Kalman Filter  [PDF]
Wei Gao,Ya Zhang,Jianguo Wang
Sensors , 2014, DOI: 10.3390/s140101511
Abstract: The integrated navigation system with strapdown inertial navigation system (SINS), Beidou (BD) receiver and Doppler velocity log (DVL) can be used in marine applications owing to the fact that the redundant and complementary information from different sensors can markedly improve the system accuracy. However, the existence of multisensor asynchrony will introduce errors into the system. In order to deal with the problem, conventionally the sampling interval is subdivided, which increases the computational complexity. In this paper, an innovative integrated navigation algorithm based on a Cubature Kalman filter (CKF) is proposed correspondingly. A nonlinear system model and observation model for the SINS/BD/DVL integrated system are established to more accurately describe the system. By taking multi-sensor asynchronization into account, a new sampling principle is proposed to make the best use of each sensor’s information. Further, CKF is introduced in this new algorithm to enable the improvement of the filtering accuracy. The performance of this new algorithm has been examined through numerical simulations. The results have shown that the positional error can be effectively reduced with the new integrated navigation algorithm. Compared with the traditional algorithm based on EKF, the accuracy of the SINS/BD/DVL integrated navigation system is improved, making the proposed nonlinear integrated navigation algorithm feasible and efficient.
北斗导航卫星相位中心修正
Antenna Phase Center Correction for BeiDou Navigation Satellite
 [PDF]

常志巧, 胡小工, 郭睿, 周善石, 何峰, 董恩强, 李晓杰, 董文丽
CHANG Zhiqiao
, HU Xiaogong, GUO Rui, ZHOU Shanshi, HE Feng, DONG Enqiang, LI Xiaojie, DONG Wenli

- , 2018, DOI: 10.13203/j.whugis20160140
Abstract: 北斗卫星导航系统(BeiDou navigation satellite system,BDS)发播电文时利用卫星钟差a0参数修正了B3频点相位中心与质心差异的大部分偏差,利用卫星群延时间参数(timing group delay,Tgd)修正不同频点相位中心的差异部分。该方法实质是利用各向同性的卫星钟差修正具有各向异性的天线相位中心偏差,改正精度有限。为进一步提高广播星历精度,提出了先对卫星位置进行相位中心改正,再对相位中心的轨迹进行广播星历拟合的处理方法,分别比较了两种改正方法对用户距离误差(user range error,URE)以及精密单点定位精度的影响。分析表明,两种方法都能使URE和定位精度得到提高,且新方法比利用卫星钟差a0参数的修正精度提高了约76%,定位精度提高了约12.5%,同时新方法的改正精度不受时空因素影响。利用广播星历拟合修正天线相位中心与不进行天线相位中心比较,定位精度提高约38.1%。最后分析了Tgd参数修正各频点天线相位中心不一致的残差,影响在毫米级,可以用于修正相位中心的频间差异
A Time-Domain Fingerprint for BOC Signals  [cached]
Muth B,Oonincx P,Tiberius C
EURASIP Journal on Advances in Signal Processing , 2007,
Abstract: Binary offset carrier (BOC) describes a class of spread-spectrum modulations recently introduced for the next generation of global navigation satellite systems (GNSSs). The design strategies of these BOC signals have so far focused on the spectral properties of these signals. In this paper, we present a time-domain fingerprint for each BOC signal given by a unique histogram of counted time elapses between phase jumps in the signal. This feature can be used for classification and identification of BOC-modulated signals with unknown parameters.
A Time-Domain Fingerprint for BOC(m,n) Signals  [cached]
B. Muth,P. Oonincx,C. Tiberius
EURASIP Journal on Advances in Signal Processing , 2007, DOI: 10.1155/2007/56104
Abstract: Binary offset carrier (BOC) describes a class of spread-spectrum modulations recently introduced for the next generation of global navigation satellite systems (GNSSs). The design strategies of these BOC signals have so far focused on the spectral properties of these signals. In this paper, we present a time-domain fingerprint for each BOC signal given by a unique histogram of counted time elapses between phase jumps in the signal. This feature can be used for classification and identification of BOC-modulated signals with unknown parameters.
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