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Localization of Small Mobile Robot by Low-Cost GPS Receiver 被引量:1
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《Journal of Mechanics Engineering and Automation》 2013年第8期522-528,共7页
This article deals with a problem of the robot localization in the outdoor environment by using the GPS (global positioning system) data. In order to navigate the robot, it is necessary to transform the global posit... This article deals with a problem of the robot localization in the outdoor environment by using the GPS (global positioning system) data. In order to navigate the robot, it is necessary to transform the global position into the local map in the form of two-dimensional Cartesian coordinate system. The transformation is based on the model of the Earth-WGS 84 reference ellipsoid. The aim of this article is to experimentally evaluate a set of low-cost GPS receivers applicable as position sensors for small outdoor mobile robots. The evaluation is based on series of measurements executed in different times and places. The measured data is processed by given procedure and acquired positions are transformed into the local coordinate system. Accordingly the accuracy of the measured positions is statistically evaluated. The evaluation of used GPS receivers is done by comparison with data acquired by high-end geodetic GPS system Leica 1200, which is used as a reference GPS system. 展开更多
关键词 LOCALIZATION small mobile robot GNSS (global navigation satellite system) gps receiver WGS 84 Leica gps 1200.
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Improved Circular Correlation Methods for Acquisition in Software GPS Receiver
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作者 Vandana Patel Pankaj Shukla Mithilesh Kumar 《Computer Technology and Application》 2011年第5期389-395,共7页
In this paper the authors explore the Global Positioning System (GPS) signal acquisition and tracking algorithms used in software GPS receiver. Acquisition time is the most important parameter in evaluating the perf... In this paper the authors explore the Global Positioning System (GPS) signal acquisition and tracking algorithms used in software GPS receiver. Acquisition time is the most important parameter in evaluating the performance of a software GPS receiver in terms of its speed. A trade-off study is done to seek a good balance between the acquisition accuracy and the processing time. The frequency-domain acquisition method by circular correlation, used in a software GPS receiver, has been improved by studying the power spectrum of the Coarse Acquisition (C/A) code alone. The analysis of C/A code reveals that its power spectrum is symmetrical; hence only half the points are required to perform circular correlation. Besides, either half of the spectrum is asymmetrical where a larger amount of power is concentrated in almost one-quarter of the spectrum on its either sides. This further reduces the number of points used to perform correlation. Comparative results of MATLAB simulation of full-size, half-size and quarter-size circular correlation done on actual data stored on hard disk are provided, and they agree with those obtained using GPS receiver. Further reduction in acquisition time has been achieved by investigating the effect of length of the noncoherent pre-integration period. The improved acquisition methods pave way for further development of new algorithms to enhance software GPS receiver performance. 展开更多
关键词 Global positioning system gps software gps receiver coarse acquisition (C/A) code signal acquisition circular correlation signal power spectrum.
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Fast fine acquisition algorithm of GPS receiver aided by INS information 被引量:6
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作者 Lufeng Zhu Chunxi Zhang Zhiqiang Ma 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2011年第2期300-305,共6页
Acquisition time of global position system (GPS) receiver, which is the main factor contributes to time to first fix (TTFF), can be shortened by estimating the Doppler frequency shift through external inertial nav... Acquisition time of global position system (GPS) receiver, which is the main factor contributes to time to first fix (TTFF), can be shortened by estimating the Doppler frequency shift through external inertial navigation system (INS) information and almanac data and reducing the searching area. The traditional fast acquisition is analyzed, the fast acquisition of the GPS receiver aided is presented by INS information, and the signal is fine captured by spectrum zooming. Then the algorithm is simulated by sampled GPS intermediate frequency (IF) signal and the result verifies that this acquisition can dramatically improve the capability of GPS receiver and reduce its acquisition time. 展开更多
关键词 inertial navigation system (INS) aid spectrum zooming acquisition time global position system gps receiver.
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Architecture design of GPS software receiver and implementation of its acquisition algorithm with fine frequency estimation 被引量:3
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作者 祝雪芬 陈熙源 李滋刚 《Journal of Southeast University(English Edition)》 EI CAS 2008年第1期38-41,共4页
The design of a global positioning system (GPS) software receiver is introduced. This design uses the concept of software radio, and it consists of the following parts: front-end, acquisition, tracking, synchroniza... The design of a global positioning system (GPS) software receiver is introduced. This design uses the concept of software radio, and it consists of the following parts: front-end, acquisition, tracking, synchronization, navigation solution and some assisting modules. In the acquisition module, the acquisition algorithm based on circular correlation is utilized. The input data and the local code are converted into the frequency domain by means of the fast Fourier transform (FFT). After performing circular correlation, the initial phase of the C/A code can be obtained and the cartier frequency can be found in 1 kHz frequency resolution, which is too coarse to use for the tracking loop. In order to improve the frequency resolution, the fine frequency estimation through a phase relationship is then achieved, by which, the frequency resolution is improved dramatically. Experiments show that the inaccuracy of the carrier frequency can be estimated within a few hertz by the fine frequency estimation method, and the fine frequency attained can be directly used for the tracking loop. 展开更多
关键词 gps software receiver acquisition algorithm circular correlation fine frequency estimation
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Quality assessment of onboard GPS receiver and its combination with DORIS and SLR for Haiyang 2A precise orbit determination 被引量:13
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作者 GUO Jing ZHAO QiLe +3 位作者 GUO Xiang LIU XiangLin LIU JingNan ZHOU Quan 《Science China Earth Sciences》 SCIE EI CAS CSCD 2015年第1期138-150,共13页
The GPS,DORIS,and SLR instruments are installed on Haiyang 2A(HY2A)altimetry satellite for Precise Orbit Determination(POD).Among these instruments,the codeless GPS receiver is the state-of-art Chinese indigenous onbo... The GPS,DORIS,and SLR instruments are installed on Haiyang 2A(HY2A)altimetry satellite for Precise Orbit Determination(POD).Among these instruments,the codeless GPS receiver is the state-of-art Chinese indigenous onboard receiver,and it is the first one successfully used for Low Earth Orbit(LEO)satellite.Firstly,the contribution assesses the performance of the receiver through an analysis of data integrity,numbers of all tracked and valid measurements as well as multipath errors.The receiver generally shows good performance and quality despite a few flaws.For example,L2 observations are often missing in low elevations,particularly during the ascent of GPS satellites,and the multipath errors of P1 show a slightly abnormal pattern.Secondly,the PCO(Phase Center Offset)and PCV(Phase Center Variation)of the antenna of the GPS receiver are determined in this contribution.A significant leap for Z-component of PCO up to-1.2 cm has been found on 10 October 2011.Thirdly,the obtained PCO and PCV maps are used for GPS only POD solutions.The post-fit residuals of ionosphere-free phase combinations reduce almost 50%,and the radial orbit differences with respect to CNES(Centre National d’Etudes Spatiales)Precise Orbit Ephemeris(POEs)improve about 13.9%.The orbits are validated using the SLR data,and the RMS of SLR Observed minus Computed(O-C)residuals reduces from 17.5 to 15.9 mm.These improvements are with respect to the orbits determined without PCO and PCV.Fourthly,six types of solutions are determined for HY2A satellite using different combinations of GPS,DORIS,and SLR data.Statistics of SLR O-C residuals and cross-comparison of orbits obtained in the contribution and the CNES POEs indicate that the radial accuracy of these orbits is at the 1.0 cm level for HY2A orbit solutions,which is much better than the scientific requirements of this mission.It is noticed that the GPS observations dominate the achievable accuracy of POD,and the combination of multiple types of observations can reduce orbit errors caused by data gaps and maintain more stable and continuous orbits. 展开更多
关键词 Haiyang 2A gps receiver MULTIPATH precise orbit determination phase center offset phase center variations DORIS SLR
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Calibration of GPS receivers based on IGS and CORS techniques 被引量:1
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作者 SHI Kun QIU Yunfeng +2 位作者 ZHAO Biyun NIE Jin CHEN Yuhan 《Geo-Spatial Information Science》 SCIE EI 2012年第3期213-217,共5页
Concerning the traditional methods,more technical details and more strict conditions are required for global positioning system(GPS)receiver’s calibration especially for mid and long baseline which influenced by the ... Concerning the traditional methods,more technical details and more strict conditions are required for global positioning system(GPS)receiver’s calibration especially for mid and long baseline which influenced by the environment around easily,and more investigations have to be done.In this paper,a new method on how to calibrate GPS receivers is suggested,which is based on the convenient condition that Kunming has one international GPS service station and its own continuously operating reference stations,and the method is confirmed by a test using six different types of GPS receivers.Compared with the traditional methods,the new method is more efficient by decreasing routine calibration works up to 50%. 展开更多
关键词 IGS CORS gps receiver CALIBRATION BASELINE
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Design of a low power GPS receiver in 0.18 μm CMOS technology with a ΣΔ fractional-N synthesizer 被引量:1
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作者 Di LI Yin-tang YANG +7 位作者 Jiang-an WANG Bing LI Qiang LONG Jary WEI Nai-di WANG Lei WANG Qian-kun LIU Da-long ZHANG 《Journal of Zhejiang University-Science C(Computers and Electronics)》 SCIE EI 2010年第6期444-449,共6页
A 19 mW highly integrated GPS receiver with a ΣΔ fractional-N synthesizer is presented in this paper.Fractional-N frequency synthesizer architecture was adopted in this work, to provide more degrees of freedom in th... A 19 mW highly integrated GPS receiver with a ΣΔ fractional-N synthesizer is presented in this paper.Fractional-N frequency synthesizer architecture was adopted in this work, to provide more degrees of freedom in the synthesizer design.A high linearity low noise amplifier(LNA) is integrated into the chip.The radio receiver chip was fabricated in a 0.18 μm complementary metal oxide semiconductor(CMOS) process and packaged in a 48-pin 2 mm×2 mm land grid array chip scale package.The chip consumes 19 mW(LNA1 excluded) and the LNA1 6.3 mW.Measured performances are:noise figure<2 dB, channel gain=108 dB(LNA1 included), image rejection>36 dB, and-108 dBc/Hz @ 1 MHz phase noise offset from the carrier.The carrier noise ratio(C/N) can reach 41 dB at an input power of-130 dBm.The chip operates over a temperature range of-40, 120 °C and ±5% tolerance over the CMOS technology process. 展开更多
关键词 gps receiver ΣΔ fractional-N synthesizer Image rejection Phase noise
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THE CONFIDENCE EVALUATION FOR AIRBORNE GPS DATA 被引量:1
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作者 LIU Jiyu CHEN Xiaoming 《Geo-Spatial Information Science》 2000年第1期50-56,共7页
GPS kinematic carrier phase measurements can be used to determine seven di- mension state and three attitude parameters of a motional carrier,such as an aircraft or a low- earth-orbit spacecraft,on which an antenna is... GPS kinematic carrier phase measurements can be used to determine seven di- mension state and three attitude parameters of a motional carrier,such as an aircraft or a low- earth-orbit spacecraft,on which an antenna is installed to receive GPS signals. It is known from airborne GPS test results for photogrammetry in China since 1994 that GPS carrier phase measurements in a motional environment have acquired external accuracies of ± 7. 9cm for two dimensional positions and ± 18. 1cm for point heights. This paper describes airborne GPS carrier phase -measurements with multireference stations and discusses how to evaluate the confidence of GPS kinematic data. 展开更多
关键词 airborne gps receiver gps kinematic carrier phase measurement multireferene ground station
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Portable device to assess dynamic accuracy of global positioning system(GPS)receivers used in agricultural aircraft 被引量:4
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作者 Steven J.Thomson Yanbo Huang Lowrey A.Smith 《International Journal of Agricultural and Biological Engineering》 SCIE EI CAS 2014年第2期68-74,共7页
A device was designed to test the dynamic accuracy of Global Positioning System(GPS)receivers used in agricultural aircraft and other aerial vehicles.The system works by directing a sun-reflected light beam from the g... A device was designed to test the dynamic accuracy of Global Positioning System(GPS)receivers used in agricultural aircraft and other aerial vehicles.The system works by directing a sun-reflected light beam from the ground to the aircraft using mirrors.A photo detector points downward from the aircraft to detect the light beam,and photo detection circuitry triggers an event in the guidance system data file at the aircraft’s location corresponding to the precisely georeferenced position on the ground.Construction details are presented on the mirror-based light reflection system and photo-electronic circuitry designed to trigger an event in the guidance system’s log file.An example application evaluated the horizontal accuracy of a stand-alone GPS receiver by matching dynamic data with data from the aircraft’s guidance system.Results indicated a 2.16 s lead in position registered by the stand-alone receiver over that registered by the aircraft’s guidance system GPS receiver,which had been previously evaluated to be within 0.13 s of Real-Time Kinematic(RTK)-referenced time and position. 展开更多
关键词 gps receiver accuracy agricultural aircraft aerial application remote sensing GEOREFERENCING UAV
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An RF frontend circuit design of a Compass and GPS dual-mode dual-channel image rejection radio receiver 被引量:1
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作者 张弓 陈红林 +7 位作者 刘渭 杨寒冰 张丽娟 王祥炜 石磊 胡思静 王明照 符卓剑 《Journal of Semiconductors》 EI CAS CSCD 2013年第8期127-132,共6页
This paper introduces a fully integrated low power consumption radio receiver frontend circuit for a Compass(Beidou) and GPS dual mode dual channel system with 2.5 dB NF,1.02 mm^2 areas,and 8 mA of current in 0.18μ... This paper introduces a fully integrated low power consumption radio receiver frontend circuit for a Compass(Beidou) and GPS dual mode dual channel system with 2.5 dB NF,1.02 mm^2 areas,and 8 mA of current in 0.18μm TSMC CMOS process.Except for a few passive components for input matching,other components such as an off-chip low noise amplifier or a balun are not required.With a non-tunable passive image rejection filter,the receiver frontend can achieve around 60 dB gain and 34 dB image rejection. 展开更多
关键词 compass(BeiDou) gps CMOS receiver frontend active balun image rejection
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A single-to-differential low-noise amplifier with low differential output imbalance 被引量:1
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作者 段炼 黄伟 +3 位作者 马成炎 何晓丰 金玉花 叶甜春 《Journal of Semiconductors》 EI CAS CSCD 2012年第3期60-64,共5页
This paper presents a single-ended input differential output low-noise amplifier intended for GPS applications. We propose a method to reduce the gain/amplitude and phase imbalance of a differential output exploiting ... This paper presents a single-ended input differential output low-noise amplifier intended for GPS applications. We propose a method to reduce the gain/amplitude and phase imbalance of a differential output exploiting the inductive coupling of a transformer or center-tapped differential inductor.A detailed analysis of the theory of imbalance reduction,as well as a discussion on the principle of choosing the dimensions of a transformer,are given.An LNA has been implemented using TSMC 0.18μm technology with ESD-protected.Measurement on board shows a voltage gain of 24.6 dB at 1.575 GHz and a noise figure of 3.2 dB.The gain imbalance is below 0.2 dB and phase imbalance is less than 2 degrees.The LNA consumes 5.2 mA from a 1.8 V supply. 展开更多
关键词 gps receiver single-ended input differential output BALUN low-noise amplifier TRANSFORMER
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