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本文结合高频岸-舰双基地综合脉冲孔径雷达(SIAR)的特点,利用接收到的直达波信号以及全球定位系统(GPS)测得的接收站位置信息,提出基于FFT的发射阵增益、相位以及位置误差校准方法.仅存在增益和相位误差时,校准需已知一个接收站方位;增益、相位和位置误差都存在时,需要三个接收站方位.文中推导了对这三个接收站方位的要求,研究了接收平台运动和存在多径效应时的校准方法,分析了GPS角定位误差对校准的影响.计算机仿真表明了该方法对发射阵的增益、相位以及位置误差具有良好的校正性能.由于无需精确校准的辅助阵元或方位精确已知的辅助信源,并且运算量小,该方法易于工程实现. 相似文献
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为了提高室内环境下对目标的定位精度,提出一种室内单站精确定位技术. 该技术利用室内电波传播多径效应构成的复杂信道信息,基于机器学习,构建卷积神经网络架构,通过卷积提取不同位置目标到达接收传感器的多径时延特征信息;然后通过多层全连接层深度神经网络的模型训练,将基于复杂信道的定位问题转化为回归模型的问题,建立信道指纹与位置之间的非线性关系来完成被动定位. 训练和仿真结果表明,在室内复杂电波传播环境下,基于神经网络的室内单站精确定位技术能够实现单接收站情况下对目标的精确定位. 本文主要对3×3网格大小的金属散射体进行定位,接收站位于室内时,平均定位误差为0.621个网格(12.42 cm);接收站位于室外时,能够分别实现信噪比20 dB、30 dB、40 dB情况下44.09 cm、21.42 cm、20.96 cm的平均定位误差. 本文方法为室内复杂环境下的目标定位提供了一种新的定位方法. 相似文献
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针对多基地无源雷达中对单目标的定位问题,提出一种利用角度信息的加权最小二乘定位算法。设计了基于角度的目标定位模型,并根据不同的角度测量噪声设计了加权矩阵,进行了误差分析并推导了算法的Cramer-Rao界。仿真分析表明,本文算法优于同类算法,并且以3个接收站与一个外辐射源为例,给出了最佳位置配置建议。 相似文献
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针对距离-速度复合欺骗干扰,本文提出了一种基于多维信息联合的多基地雷达欺骗干扰抑制技术。首先,在各接收站中通过常规信号处理方法提取到真假目标的多维信息矩阵;接着在融合中心,基于真假目标幅度上的统计差异,进行干扰识别;然后,鉴于真实目标的多普勒多样性,进行多普勒维上的干扰识别;最后,根据目标的“同源性”,在距离维将虚假目标完全识别的同时,完成了对真实目标定位。通过数字仿真可见,该方法在保证了真实目标识别率的基础上,实现了对复合欺骗干扰的有效抑制和对真实目标的准确定位。 相似文献
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针对利用单个观测接收站接收数个外辐射源信号进行目标定位过程中,传统解析定位算法估计精度不够理想的问题,提出了一种利用约束加权最小二乘(CWLS)到达时差的定位算法。首先将目标到观测接收站的距离作为冗余参量,实现时差观测方程的线性化,然后根据目标到观测接收站的距离与目标位置之间的函数关系,建立为CWLS定位模型,并采用拉格朗日乘子式(Lagrange multiplier)求解该类带约束条件的CWLS问题。同时,还推导了相应的克拉美罗界(CRLB)和理论误差。通过仿真实验和分析可以表明,在存在测量误差的情况下,本文提出的新算法仍然能够逼近CRLB,且与解析方法相比,具有较好的定位精度。 相似文献
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针对运动目标到达时差(Time Difference-of-Arrival,TDOA)/到达频差(Frequency Difference-of-Arrival,FDOA)定位中的接收站定位误差问题,提出了基于多校准站的TDOA/FDOA定位方法,有效降低接收站定位误差的影响,并推导了该方法的克拉美罗下限(Cramér-Rao Lower Bound,CRLB)。理论分析表明,采用多校准站法能有效降低CRLB,提高目标定位精度。同时,当校准站自身定位存在误差时,也将影响对接收站的校准和目标的定位精度。通过仿真实验定量分析了采用多校准站法对定位精度的改善程度。 相似文献
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在电子对抗系统中,无源定位跟踪系统由于本身不发射电磁波,具有很好的隐蔽性,而提取辐射电磁信号中携带的定位信息的参数,则是实现无源定位的前提和关键.对GPS卫星系统信号加以利用,通过计算出目标反射GPS卫星信号的回波信号相对于直达信号的时延和多普勒频移信息,仿真了一种新的估计算法,为目标的定位提供了基础. 相似文献
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Global positioning system (GPS) receivers find growing applications in indoor and outdoor communication environments, including urban and rural areas. Interference and noise sources for GPS receivers may assume Gaussian or non-Gaussian distributions. The GPS receiver performance under Gaussian additive noise has been studied. Non-Gaussian noise may equally contaminate the GPS satellite signals and disturb the receiver delay lock loops (DLL), producing significant tracking errors. These sources include impulsive noise, ultra-wideband (UWB) signals, and impulse and noise radar signals for target tracking and indoor imaging applications. This paper considers non-Gaussian noise of finite variance and examines its effect on the discriminator outputs for the commercial GPS receiver that uses the coarse acquisition (C/A) code. The correlator noise output components are produced from the correlation between the noise sequence and the early, late, and punctual reference C/A code. Due to the long time averaging, which is characteristic of the GPS correlation loops, these components assume Gaussian distributions. The discriminator tracking error variance is derived, incorporating the effect of noise, the front-end precorrelation filter, and the sampling rate. 相似文献
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分析了GPS(全球定位系统)/GLONASS(全球卫星导航系统)双星接收机双星定位的原理,目的是解决多站雷达高精度定位中接收数据差分解算的失效,提出在GLONASS变化时把导航数据文件.jps转换成Rinex后再用Pinnacle处理或将双星接收机设置为单一的GPS模式下导航数据用Pinnacle处理的方法,用这两种方法处理的导航数据可进行差分解算,计算的定位精度满足设计要求。 相似文献
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Development and use of a GPS ionospheric scintillation monitor 总被引:5,自引:0,他引:5
Global Positioning System (GPS) satellite signals provide convenient radio beacons for ionospheric studies. Among other propagation phenomena, the ionosphere affects GPS signal propagation through amplitude scintillations that develop after radio waves propagate through ionospheric electron density irregularities. This paper outlines the design, testing, and operation of a specialized GPS receiver to monitor L-band amplitude scintillations: the Cornell scintillation monitor. The Cornell scintillation monitor consists of a commercial GPS receiver development kit with its software modified to log signal strength from up to 12 channels at a high data rate (50 samples/s). Other features of the receiver include the optional assignment of a channel to monitor the receiver noise level in the absence of signal tracking and the means to synchronize measurements between nearby independent receivers to perform drift measurements and correlation studies. The Cornell scintillation monitor provides characterization of the operational L-band scintillation environment and additionally permits study of the multipath environment of a static antenna, GPS scintillation monitors can provide information about the state of ionospheric irregularities for pure research purposes as well. Their strength lies in the fact that they are inexpensive and compact and therefore can he readily proliferated. Even a single scintillation monitor can supplement radar spatial coverage of irregularities in a limited way because it monitors several satellite lines of sight simultaneously 相似文献
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当前船载防碰撞装置大致有两种,一是采用雷达装置,但存在价格贵且不能进行统一管理与调度的不足,二是GPS接收机,价格便宜但对移动物体不能防碰.为此,提出了一种新型基于GPS+GPRS的船载防碰撞装置,同时,在监控中心,通过系统模型和去漂移算法,计算出两艘或多艘移动船只避碰的可能性,成本低,是传统两种防碰装置完美结合. 相似文献
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高动态GPS模拟器信号产生模型研究 总被引:2,自引:0,他引:2
高动态GPS卫星信号模拟器可以根据载体的动态环境,精确产生载体收到的GPS卫星信号.在对GPS接收机接收信号进行深入分析后发现GPS信号模拟器以接收时刻为标准以一定的时间间隔计算模拟器信号码和载波速率及信号的传播延时,由于接收机与GPS星之间存在的径向加速度,使得对应的信号发出时刻的间隔不等于计算机进行样点计算的间隔.本文给出了在高动态条件下GPS卫星信号模拟器的信号模型,在对模型误差进行分析计算的基础上讨论了通过增加采样率来减小由于模拟高加速度信号而带来的误差的方法. 相似文献
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F. M. Jumaah A. A. Zaidan B. B. Zaidan R. Bahbibi M. Y. Qahtan A. Sali 《Telecommunication Systems》2018,68(3):425-443
Global positioning system (GPS) has undergone intensive development, starting as an advanced specialized tool to a general-purpose gadget used in our daily lives. GPS exists in new technologies, applications, and consumer products, especially in smartphones and tablets. In a GPS receiver design, power consumption and localization accuracy are critical factors that affect the outcome of a GPS receiver system. Theoretically, increasing the number of required tracking channels in a GPS baseband receiver increases the design complexity and size of this system. Thus, power consumption can significantly increase. The receiver should acquire and track numerous satellites to improve the location accuracy of a position, thereby indicating that the receiver requires a high number of tracking channels. Thus, optimizing these tracking channels to balance the conflict among performance parameters is a difficult and challenging task. This paper presents a technique for order performance by similarity to ideal solution (TOPSIS) for solving complex situations for multi-criteria optimization of the tracking channels of GPS baseband telecommunication receiver. Nine operation modes of GPS receiver were evaluated by each design parameter, such as power consumption, localization accuracy, and time with no position available for static and dynamic positioning. Then, the TOPSIS was utilized and implemented to measure and rank the overall performance of tracking channel selection. Results of this study indicate that (1) multi-objective optimization is a reliable strategy for visualizing the trade-off among the GPS design parameters and providing a dynamic power consumption planning. (2) The best aggregated performance of the GPS receiver occurs when the number of tracking channels equals five and six for static and dynamic positioning, respectively. (3) The most frequent number of available satellites is eight, whereas the other number of satellites is a rare case to acquire. However, GPS standards require that available GPS satellites are constantly 12 at any time and place. 相似文献
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介绍了GPS测风系统的构成、GPS接收机的性能指标和从GPS定位信息反演大气风场的方法,GPS接收机的性能指标与反演的风场数据的精度和可靠性关系密切.为了验证GPS测风技术的可靠性,进行了和风廓线仪、Vaisala探空的对比实验,结果表明:GPS探空和风廓线仪及Vaisala气球测风的结果相关性都很好,风速、风向廓线较为接近,但GPS测得的风速平均值比风廓线仪和Vaisala的测量结果均偏大.进一步分析了GPS测风产生偏差的原因,对误差做出合理的订正十分必要. 相似文献